HeadLice.Org Hot Spots

The Human Louse and Disease
Recent Studies Support the Critical Need for Preparedness and Lice Prevention

"One of the greatest achievements in the war which the medical sciences have waged against epidemic diseases is the discovery that, during times of quiescence in interepidemic periods, the potential agents of disease may smolder in human carriers, in domestic animals - especially rodents, - and in insects." Hans Zinsser - Rats, Lice and History

Pediculosis capitis is the medical term for an infestation of head lice. It is itself an infectious disease.

Head lice are highly communicable parasites specific to humans. They require blood meals to survive and have been associated with various infections including rickettsial diseases. Newer technologies are validating research done by bench workers on this subject many decades ago. Additional studies are required as new emerging or re-emerging pathogens occur.

As the threat of old and new communicable diseases emerge, it is critical to set public health standards that not only encourage, but also enable parents to send their children to school lice and nit free.

The following is a partial list of both classic and recent research studies involving louse-borne diseases. This list continues to grow so check back.

Scalp microbiota alterations in children with pediculosis.
2019 May
"Pediculosis is a disease caused by the insect Pediculus humanus capitis that mainly occurs in childhood. A comparative study was carried out evaluating groups of schoolchildren with (group A) and without pediculosis (group B) to analyse the characteristics of the scalp microbiota. Samples were collected by swab using Stuart transport medium and incubate in Sabouraud dextrose agar with tetracycline to analyse the fungal microbiota and in blood agar to assess the bacterial microbiota. The isolates identity was confirmed by sequencing of the 16S and 18S regions of the ribosomal DNA gene for bacteria and fungi, respectively. The analysis of the 186 isolates led to the identification of 35 bacteria and 40 fungi in group A and 47 bacteria and 64 fungi in group B. The results indicate differences in bacterial and fungal species in the groups analysed. In the observed bacterial microbiota, Staphylococcus capitis occurred more frequently than Staphylococcus epidermidis in group A vs B. Among fungal isolates, Debaryomyces sp. was more frequent in group B vs A. Our findings showed scalp microbiota alterations in children with pediculosis, meriting future studies to analyse the relationship between these agents and their impact on human health."
Haidamak J1, Dos Santos GD1, de Souza Lima BJF1, Soares VM2, de Menezes RV3, Bisson AA4, Talevi AS3, Gomes RR5, Vicente VA5, Valero MA6, do Rocio Klisiowicz D7. Infect Genet Evol.
Head Lice Recognize and Prefer Head Odor Over Foot and Forearms Odors.
2019 May
"Human head lice, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), are hematophagous parasites that infest human heads. They are extreme host specialists suggesting a strict selection behavior towards the human head by the parasites. Despite the public health relevance of P. humanus capitis, the role of chemical clues to select the human head is not well known. In the present study, we attempted to find out whether head lice recognize and select the odor of the head over the odor of other parts of the human body. Our results using a two-choice olfactometer demonstrated that head lice were highly attracted by the volatile compounds of the human odor air, but they did not show preference for the volatiles of head compared to the volatiles of other parts of the body (forearm or foot). Conversely, when head lice were exposed in an experimental arena to the whole human odor of different parts of the body, they showed a preferential response to the whole head odor compared with the whole foot or forearm odors. These results suggest that head lice can at short distance of the host, be oriented towards the head odor of the human host in the selection of the scalp environment."
Galassi F1, Gonzalez-Audino P1, Picollo MI1. J Med Entomol. 2019 May 14. pii: tjz060. doi: 10.1093/jme/tjz060. [Epub ahead of print]
Report of the human body louse (Pediculus humanus) from clothes sold in a market in central Italy.
2019 May
"Pediculus humanus, the human body louse, is widespread where overcrowding and lack of hygiene are present, in areas of the world affected by poverty, war, famine and presence of refugees. It has recently been considered re-emerging among homeless populations in developed countries. In Italy, it was last reported in 1945. Pediculus humanus is a vector of highly relevant human pathogens."
De Liberato C1, Magliano A2, Romiti F2, Menegon M3, Mancini F3, Ciervo A3, Di Luca M3, Toma L3. Parasit Vectors. 2019 May 3;12(1):201. doi: 10.1186/s13071-019-3458-z
The Sensory Machinery of the Head Louse Pediculus humanus capitis: From the Antennae to the Brain..
2019 May
"Insect antennae are sophisticated sensory organs, usually covered with sensory structures responsible for the detection of relevant signals of different modalities coming from the environment. Despite the relevance of the head louse Pediculus humanus capitis as a human parasite, the role of its antennal sensory system in the highly dependent relation established with their hosts has been barely studied. In this work, we present a functional description of the antennae of these hematophagous insects by applying different approaches, including scanning electron microscopy (SEM), anterograde antennal fluorescent backfills, and behavioral experiments with intact or differentially antennectomized lice. Results constitute a first approach to identify and describe the head louse antennal sensilla and to determine the role of the antenna in host recognition. SEM images allowed us to identify a total of 35-40 sensilla belonging to seven different morphological types that according to their external architecture are candidates to bear mechano-, thermo-, hygro-, or chemo-receptor functions. The anterograde backfills revealed a direct neural pathway to the ipsilateral antennal lobe, which includes 8-10 glomerular-like diffuse structures. In the two-choice behavioral experiments, intact lice chose scalp chemicals and warm surfaces (i.e., 32°C) and avoided wet substrates. Behavioral preferences disappeared after ablation of the different flagellomeres of their antenna, allowing us to discuss about the location and function of the different identified sensilla. This is the first study that integrates morphological and behavioral aspects of the sensory machinery of head lice involved in host perception."
Ortega Insaurralde I1, Minoli S2, Toloza AC1, Picollo MI1, Barrozo RB2. PFront Physiol. 2019 Apr 18;10:434. doi: 10.3389/fphys.2019.00434. eCollection 2019.
Prevalence of Ectoparasitic Infections and Other Dermatological Infections and Their Associated Factors among School Children in Gampaha District, Sri Lanka.
2019 May
"Skin disorders are one of the commonest conditions among school children in developing countries. There are only a few published studies available from Sri Lanka on the prevalence of skin disorders. A community-based cross-sectional study was carried out among five government-run schools randomly selected from the district of Gampaha, Sri Lanka, during 2016-2017. A total of 41 students between 5 and 16 years of age were randomly selected from each school. Sociodemographic profile and hygienic behaviors of selected students were assessed using a pretested interviewer-administered questionnaire. Students were examined by a medical officer for the presence of different skin disorders. The chi-squared test of association and binary logistic regression were used for the identification of the significance of socioeconomic factors and hygienic practices among the study participants. A total of 205 school children participated in the study. The commonest skin disorder was pediculosis (42.0%; n=86), followed by dandruff (8.3%; n=17), fungal infections (6.8%; n=14), and scabies (1.5%; n=3). Almost one-fourth of the study participants (22.9%; n=30/131) had more than one disorder, majored by Pediculus captis infestation with dandruff. Over one-third (36.1%; n=74) were free of any skin disorders. The prevalence of skin disorders was significantly high among females (87.3%; n=110), compared to males (26.6%; n=21). Presence of long hair, higher family size, and limited number of rooms in the house were risk factors associated with the prevalence of skin disorders. The commonest skin disorder was pediculosis, while scabies and fungal infections were scarce among school children in the district of Gampaha, Sri Lanka. Implementation of health education and monitoring programs at the school level for maintaining the dermal health status of school children is recommended."
Gunathilaka N1, Chandrasena N1, Udayanga L2. Can J Infect Dis Med Microbiol. 2019 Mar 25;2019:5827124. doi: 10.1155/2019/5827124. eCollection 2019.
Louse-borne relapsing fever (Borrelia recurrentis infection).
2019 March
"Louse-borne relapsing fever (LBRF) is an epidemic disease with a fascinating history from Hippocrates' times, through the 6th century 'Yellow Plague', to epidemics in Ireland, Scotland and England in the 19th century and two large Afro-Middle Eastern pandemics in the 20th century. An endemic focus persists in Ethiopia and adjacent territories in the Horn of Africa. Since 2015, awareness of LBRF in Europe, as a re-emerging disease, has been increased dramatically by the discovery of this infection in dozens of refugees arriving from Africa.The causative spirochaete, Borrelia recurrentis, has a genome so similar to B. duttonii and B. crocidurae (causes of East and West African tick-borne relapsing fever), that they are now regarded as merely ecotypes of a single genomospecies. Transmission is confined to the human body louse Pediculus humanus corporis, and, perhaps, the head louse P. humanus capitis, although the latter has not been proved. Infection is by inoculation of louse coelomic fluid or faeces by scratching. Nosocomial infections are possible from contamination by infected blood. Between blood meals, body lice live in clothing until the host's body temperature rises or falls, when they seek a new abode.The most distinctive feature of LBRF, the relapse phenomenon, is attributable to antigenic variation of borrelial outer-membrane lipoprotein. High fever, rigors, headache, pain and prostration start abruptly, 2-18 days after infection."
Warrell DA1. Epidemiol Infect. 2019 Jan;147:e106. doi: 10.1017/S0950268819000116.
Identification of Arthropods By Polymerase Chain Reaction As Probes For Infectious Disease Studies In Experimental Coprolites.
2019 February
"The study of arthropods is still scarce in paleoparasitology, especially their molecular identification. In this experimental study, we amplify DNA using a polymerase chain reaction from 2 ectoparasite species, Rhipicephalus sanguineus and Pediculus humanus capitis, in experimentally desiccated feces. This study shows perspectives for the study of the identification of arthropods in coprolites when taxonomic identification is not possible."
Pucu E1, Lemos E2, Rozental T2, Ogrzewalska M2, Chame M3, Machado-Silva JR4, Leles D1. J Parasitol. 2019 Feb;105(1):133-134.
Killing Clothes Lice by Holding Infested Clothes away from Hosts for 10 Days to Control Louseborne Relapsing Fever, Bahir Dah, Ethiopia
2019 February
"Louseborne relapsing fever (LBRF) was once a cosmopolitan disease but it now occurs only in the Horn of Africa. Recent cases in refugees to Europe made LBRF topical again. Crowded boarding houses and church dwellings in Ethiopia are analogous to the crowded air-raid shelters of World War II. Thus, we might learn from experiments the London School of Tropical Hygiene and Medicine conducted during World War II. When the vector of Borrelia recurrentis (Pediculus humanus lice) were held away from the host for 10 days, 100% of nymphal and adult lice starved to death and 100% of eggs did not hatch. We hypothesize that holding infested clothes away from hosts in plastic shopping bags will kill enough lice to control LBRF in Ethiopia. Owning 2 sets of clothes might be useful; 1 set might be held in a plastic shopping bag for 10 days to kill lice and their eggs."
Stephen C. Barker and Dayana Barker. Emerging Infectious Diseases. 2019; Volume 25, Number 2.
A review of the genus Rickettsia in Central America
2018 October
"In this study, we demonstrate that the genus Rickettsia is widely distributed in Central America and that rickettsiosis could be an underestimated problem in the absence of greater diagnostic efforts in undetermined febrile cases."
C Sergio E Bermúdez and Adriana Troyo. Res Rep Trop Med. 2018; 9: 103–112.
Effect of a health education program on reduction of pediculosis in school girls at Amphoe Muang, Khon Kaen Province, Thailand
2018 October
"The NPA's model of educating the community and combing: 'Effect of a health education program on reduction of pediculosis in school girls at Amphoe Muang, Khon Kaen Province, Thailand.'"
PLoS One
New approaches in the systematics of rickettsiae
2018 June
"The development of a formal order analysis (FOA) allowed constructing a classification of 49 genomes of Rickettsiaceae family representatives. Recently FOA has been extended with new tools—‘Map of genes,’ ‘Matrix of similarity’ and ‘Locality-sensitive hashing’—for a more in-depth study of the structure of rickettsial genomes. The new classification confirmed and supplemented the previously constructed one by determining the position of Rickettsia africae str. ESF-5, R. heilongjiangensis 054, R. monacensis str. IrR/Munich, R. montanensis str. OSU 85- 930, R. raoultii str. Khabarovsk, R. rhipicephali str. 3-7-female6-CWPP and Rickettsiales bacterium str. Ac37b. The ‘Map of genes’ demonstrated the complete genomes and their components in a graphical form. The ‘Matrix of similarity’ was applied for an in-depth classification to a subtaxonomic category of the strain within the species R. rickettsii (11 strains) and R. prowazekii (ten strains). The ‘Matrix of similarity’ determines the degree of homology of complete genomes by pairwise comparison of their components and identification of those being identical and similar in the arrangement of nucleotides. A new genomosystematics approach is proposed for the study of complete genomes and their components through the development and application of FOA tools. Its applications include the development of principles for the classification of microorganisms, based on the analysis of complete genomes and their annotations. This approach may help in the taxonomic classification and characterization of some Candidatus Rickettsia spp. that are found in large numbers in arthropods worldwide"
S. N. Shpynov, P.-E. Fournier, N. N. Pozdnichenko, A. S. Gumenuk3 and A. A. Skiba. New Microbes and New Infections, Volume 23 Number C, May 2018
New approaches in the systematics of rickettsiae
2018 May
"The development of a formal order analysis (FOA) allowed constructing a classification of 49 genomes of Rickettsiaceae family representatives. Recently FOA has been extended with new tools—‘Map of genes,' 'Matrix of similarity’ and 'Locality-sensitive hashing' - for a more in-depth study of the structure of rickettsial genomes."
S.N.Shpynov.-E.Fournier.N.Pozdnichenko.S.Gumenuk.A.Skiba. New Microbes and New Infections. Volume 23, May 2018, Pages 93-102.
Detection of bacterial pathogens in clade E head lice collected from Niger's refugees in Algeria
2018 May
"Head lice, Pediculus humanus capitis, are obligate blood-sucking parasites. Phylogenetically, they occur in five divergent mitochondrial clades (A, D, B, C and E), each having a particular geographical distribution. Recent studies have revealed that head lice, as is the case of body lice, can act as a vector for louse-borne diseases. Here, we aimed to study the genetic diversity of head lice collected from Niger's refugees (migrant population) arriving in Algeria, northern Africa, and to look for louse-borne pathogens. Comparative head lice samples collected from indigenous population of schoolchildren (non-immigrant) were also analyzed to frame the study."
Parasit Vectors. 2018 Jun 15.
Molecular Survey of Head and Body Lice, Pediculus humanus, in France
2018 May
"Human lice, Pediculus humanus, are obligate blood-sucking parasites. Phylogenetically, they belong to several mitochondrial clades exhibiting some geographic differences. Currently, the body louse is the only recognized disease vector, with the head louse being proposed as an additional vector. In this article, we study the genetic diversity of head and body lice collected from Bobigny, a town located close to Paris (France), and look for louse-borne pathogens."
Vector Borne Zoonotic Dis. 2018 May.
Body lice of homeless people reveal the presence of several emerging bacterial pathogens in northern Algeria
2018 April
"Recently, head lice belonging to different mitochondrial clades were found to carry the DNA of several bacterial body louse-borne pathogens, such as B. quintana, B. recurrentis, Acinetobacter species and Y. pestis in natural settings [14,16,20,33±38]. Experimental studies have also demonstrated that head lice may also act as a vector of louse-borne diseases"
PLoS Negl Trop Dis. 2018 Apr 17.
Insights About Head Lice Transmission From Field Data and Mathematical Modeling
2018 Feb
"Head lice infest millions of school-age children every year, both in developed and developing countries. However, little is known about the number of lice transferred among children during school activities, because direct methods to study this are almost impossible to implement. This issue has been addressed following an indirect method, which consist in collecting data of real infestation from several children groups and using a mathematical model of lice colonies to infer how the infestation observed might have evolved. By determining the events that would most likely lead to infestations as those observed, we find that severe infestations are most likely initiated by a relatively large number of lice transferred at the same moment or within relatively short time spans. In turn, analysis of the data obtained from screenings of the same groups of children a few days apart shows evidence of such transmission events. Interestingly, only children with severe infestations could harbor the lice necessary for this type of transmission. Thus, they play the same role as 'superspreaders' in epidemiology. As part of our experimental study it is also shown that a simple procedure of combing can be very effective to remove all mobile lice, and thus could be used as an effective preventive measure against those severe infestations that are responsible for the spread of pediculosis."
J Med Entomol. 2018 Feb 22.
Response of Pediculus humanus capitis (Phthiraptera: Pediculidae) to Volatiles of Whole and Individual Components of the Human Scalp
2018 Jan
"The head louse Pediculus humanus capitis (De Geer) (Phthiraptera: Pediculidae) is a cosmopolitan human ectoparasite causing pediculosis, one of the most common arthropod parasitic conditions of humans. The mechanisms and/or chemicals involved in host environment recognition by head lice are still unknown. In this study, we evaluated the response of head lice to volatiles that emanate from the human scalp. In addition, we identified the volatile components of the odor and evaluated the attractive or repellent activity of their pure main components. The volatiles were collected by means of Solid Phase microextraction and the extract obtained was chemically analyzed by gas chromatograph-mass spectrometer. Twenty-four volatile were identified in the human scalp odor, with the main compounds being the following: nonanal, sulcatone, geranylacetone, and palmitic acid. Head lice were highly attracted by the blend human scalp volatiles, as well as by the individual major components. A significant finding of our study was to demonstrate that nonanal activity depends on the mass of the compound as it is repellent at high concentrations and an attractant at low concentrations. The results of this study indicate that head lice may use chemical signals in addition to other mechanisms to remain on the host."
J Med Entomol. 2018 Jan 20.
Pediculus capitis in schoolchildren of the urban area of Nuevo León, México: Analyses of associated factors
2017 Sept
"Pediculosis capitis is a recurring problem affecting 6 to 12 millions of children annually; there are no epidemiological data on this subject in the state of Nuevo León, and there are few in México. Therefore, new contributions are needed to design control strategies based on factors that may predispose to head lice infestation... Our results showed that the P. capitis prevalence in Nuevo León is one of the highest in Mexico, that it constitutes a real public health problem, and that there is need to establish prevention programs at home and school to decrease or to control P. capitis with the support of public health authorities."
Rickettsia Prowazekii (Epidemic Typhus)
2017 Sept
"The human body louse is only a vector and not a reservoir because infected lice die five to seven days after they become infected with R. prowazekii. R. prowazekii multiplies in the gut epithelium of the louse which then detaches, ruptures, and releases rickettsiae into the feces. Rickettsiae from the infected feces enter the skin via abrasions or bite site and access the human host."
Sami M. Akram; Vidhya Prakash.
Detection of bacterial pathogens including potential new species in human head lice from Mali
2017 Sept
"In poor African countries, where no medical and biological facilities are available, the identification of potential emerging pathogens of concern at an early stage is challenging. Head lice, Pediculus humanus capitis, have a short life, feed only on human blood and do not transmit pathogens to their progeny. They are, therefore, a perfect tool for the xenodiagnosis of current or recent human infection. This study assessed the occurrence of bacterial pathogens from head lice collected in two rural villages from Mali, where a high frequency of head lice infestation had previously been reported, using molecular methods. Results show that all 600 head lice, collected from 117 individuals, belonged to clade E, specific to West Africa. Bartonella quintana, the causative agent of trench fever, was identified in three of the 600 (0.5%) head lice studied."
Identification of Novel Voltage-Gated Sodium Channel Mutations in Human Head and Body Lice (Phthiraptera: Pediculidae)
2017 Sept
"In recent years, the increase of head louse infestation in Iran (7.4%) and especially in West-Azerbaijan Province (248%) has raised the hypothesis of insecticide resistance development. There are different mechanisms of resistance to various groups of insecticides, and knockdown resistance (kdr) is a prominent mechanism of resistance to pyrethroids, an insecticide group which is used conventionally for pediculosis control. For detection of kdr-type well-known amino acid substitutions (M815I-T917I-L920F) and additional sodium channel mutations potentially associated with kdr resistance in head and body lice, louse populations were collected from West-Azerbaijan and Zanjan Provinces of Iran."
Journal of Medical Entomology.
Comparison of the proliferation and excretion of Bartonella quintana between body and head lice following oral challenge
2017 June
"Human body and head lice are highly related haematophagous ectoparasites but only the body louse has been shown to transmit Bartonella quintana, the causative agent of trench fever. The mechanisms by which body lice became a vector for B. quintana, however, are poorly understood. Following oral challenge, green fluorescent protein-expressing B. quintana proliferated over 9 days postchallenge with the number of bacteria being significantly higher in whole body vs. head lice."
Insect Molecular Biology.
Lice and their bacterial sidekicks have evolved together for millions of years
2017 April
"A Florida Museum of Natural History study provides new insights into the complex, shared history between blood-sucking lice and the vitamin-producing bacterial sidekicks that enable them to parasitize mammals, including primates and humans. Lice depend on bacteria to supply essential vitamins missing from blood, their only food source."
Lice and bacteria, partners in parasitism
2017 April
"Head lice have been stigmatized, quickly conjuring images of infested school children and parents combing through their hair. This social stigma reaches many of the estimated 14 million people who are annually infested in the U.S. alone. However, these blood sucking lice have had a long and complex evolutionary history tied to humans and other mammals. In total, there are 532 species of blood sucking lice and each species parasitizes one or just a few mammal species."
Head lice is more common than you think
2017 April
"From time to time, head lice infestations become news stories, especially when treatment “failures” occur. You probably feel itchy right now just thinking about them! Head lice, scientifically known as Pediculus humanus capitis, have been around as long human beings have existed. After all, lice need human blood to live."
Guide Health.
Louse-borne relapsing fever in a refugee from Mali
2017 February
"Due to the increasing number of refugees from East Africa, louse-borne relapsing fever (LBRF) has become an emergent disease in Europe. No single case of LBRF has been reported in Europe in refugees from other parts of Africa."
Source: Grecchi C1, Zanotti P2, Pontarelli A3, Chiari E2, Tomasoni LR4, Gulletta M4, Barbui A5, Caligaris S4, Matteelli A2, Castelli F2.. Infection.
Efficacy of Peer Education for Adopting Preventive Behaviors against Head Lice Infestation in Female Elementary School Students: A Randomised Controlled Trial
2017 January
"Peer education based on HBM (Health Belief Model) is an effective strategy to promote preventive behaviors against pediculosis in among fifth grade female elementary school students in Iran."
Source: Mahdi Moshki, Fereshteh Zamani-Alavijeh, Mehdi Mojadam PLOS ONE.
Head Lice of Pygmies Reveal the Presence of Relapsing Fever Borreliae in the Republic of Congo
2016 December
"Head lice, Pediculus humanus capitis, occur in four divergent mitochondrial clades (A, B, C and D), each having particular geographical distributions. Recent studies suggest that head lice, as is the case of body lice, can act as a vector for louse-borne diseases. Therefore, understanding the genetic diversity of lice worldwide is of critical importance to our understanding of the risk of louse-borne diseases... Our study is the first to show the presence of B. recurrentis in African pygmies’ head lice in the Republic of Congo. This study is also the first to report the presence of DNAs of B. theileri and several species of Acinetobacter in human head lice. Further studies are needed to determine whether the head lice can transmit these pathogenic bacteria from person to another."
Source: Nadia Amanzougaghene, Jean Akiana, Géor Mongo Ndombe, Bernard Davoust, Nardiouf Sjelin Nsana, Henri-Joseph Parra, Florence Fenollar, Didier Raoult , Oleg Mediannikov. PLOS - Neglected Tropical Diseases.
Head Lice Epidemiology, Biology, Diagnosis, and Treatment
2016 November
"Conflicting information about the proper treatment of head lice has given rise to uncertainty among patients and treating personnel. For example, the reported efficacy of permethrin fell from 97% in the 1990s to 30% in 2010."
Source: Laura Meister, Dr. med. and Falk Ochsendorf, Prof. Dr. med. Dtsch Arztebl Int. 2016 Nov; 113(45): 763–772.
High Ancient Genetic Diversity of Human Lice, Pediculus humanus, from Israel Reveals New Insights into the Origin of Clade B Lice
2016 October
"Though head lice have been found in nature to carry the DNA of Bartonella quintana, Borrelia recurrentis, Acinetobacter baumannii and Yersinia pestis [5, 8, 9, 10, 11, 12, 13], and experimental infections have shown that these lice can also act as a vector of louse-borne diseases [14, 15], their epidemiological significance is still debated."
Source: Nadia Amanzougaghene, Kosta Y. Mumcuoglu, Florence Fenollar, Shir Alfi, Gonca Yesilyurt, Didier Raoult, Oleg Mediannikov. PLoS ONE 11.
Fourth case of louse-borne relapsing fever in Young Migrant, Sicily, Italy, December 2015. Mini Review Article
2016 October
"Currently louse-borne relapsing fever (LBRF) is primarily found in limited endemic foci in Ethiopia, Somalia and Sudan; no case of imported LBRF has been reported in Europe in the 9 years prior to 2015. The aim of our paper is to describe a new case of imported LBRF detected in Sicily, Italy, and to review all cases reported in migrants arrived in Europe in the last 10 years."
Source: Colomba C1, Scarlata F2, Di Carlo P2, Giammanco A2, Fasciana T2, Trizzino M2, Cascio A2. The Royal Society for Public Health.
The History of Epidemic Typhus
2016 August
"Epidemic typhus caused by Rickettsia prowazekii is one of the oldest pestilential diseases of humankind. The disease is transmitted to human beings by the body louse Pediculus humanus corporis and is still considered a major threat by public health authorities, despite the efficacy of antibiotics, because poor sanitary conditions are conducive to louse proliferation. Epidemic typhus has accompanied disasters that impact humanity and has arguably determined the outcome of more wars than have soldiers and generals. The detection, identification, and characterization of microorganisms in ancient remains by paleomicrobiology has permitted the diagnosis of past epidemic typhus outbreaks through the detection of R. prowazekii. Various techniques, including microscopy and immunodetection, can be used in paleomicrobiology, but most of the data have been obtained by using PCR-based molecular techniques on dental pulp samples. Paleomicrobiology enabled the identification of the first outbreak of epidemic typhus in the 18th century in the context of a pan-European great war in the city of Douai, France, and supported the hypothesis that typhus was imported into Europe by Spanish soldiers returning from America. R. prowazekii was also detected in the remains of soldiers of Napoleon's Grand Army in Vilnius, Lithuania, which indicates that Napoleon's soldiers had epidemic typhus. The purpose of this article is to underscore the modern comprehension of clinical epidemic typhus, focus on the historical relationships of the disease, and examine the use of paleomicrobiology in the detection of past epidemic typhus outbreaks."
Source: Angelakis E, Bechah Y, Raoult D. Microbiol Spectr. 2016 Aug;4(4). doi: 10.1128/microbiolspec.PoH-0010-2015. - August 2016.
An outbreak of pubic louse infestation on the scalp hair of elderly women.
2016 July
An outbreak of pubic louse infestation on the scalp hair of elderly women was recently documented in July 2016.
Source: Eto A1, Nakamura M1, Ito S1, Tanaka M1, Furue M2. J Eur Acad Dermatol Venereol. 2016 Jul 22. .
Louse-Borne Relapsing Fever (Borrelia recurrentis) in a Somali Refugee Arriving in Italy: A Re-emerging Infection in Europe?
2016 May
"Louse-borne relapsing fever (LBRF) is an acute febrile infection that is typically characterizedby one to three fairly regular waves of bacteremia [1,2]. It is caused by Borrelia recurrentis,amotile spirochete that measures 5 to 40 μm in length. The microorganism is transmitted fromperson to person by the human body louse (Pediculus humanus humanus). Disruptions in san-itation during wartime and mass migrations of people provide conditions that favor the propa-gation of body lice and thus the occurrence of outbreaks of the disease [1,3]. LBRF is endemicin East Africa (e.g., Ethiopia, Eritrea, Somalia, and Sudan) with the highest number of casesobserved in Ethiopia, where it is the seventh most common cause of hospital admission andthe fifth most common cause of death [4,5]. We report here the first case of imported LBRFobserved in Lombardy (northern Italy) in a Somali refugee."
Source: Spinello Antinori1, Oleg Mediannikov, Mario Corbellino, Romualdo Grande,Carlo Parravicini, Giovanna Bestetti, Erika Longhi, Davide Ricaboni, CyrilleBilé Ehounoud, Florence Fenollar, Didier Raoult, Sara Giordana Rimoldi PLoS Neglected Tropical Diseases 10(5):e0004522 - May 2016.
Severe pediculosis capitus: a case of "crusted lice" with autoeczematization
2016 May
"Pediculosis humanus capitus infestations are common and classically present with intense pruritus of the scalp. Although many treatment options are available, lice are becoming more resistant to conventional therapies and severe clinical presentations are bound to become more prevalent. We present a case of treatment-resistant pediculosis capitus resulting in diffuse autoeczematization of the torso and extremities and severe crusting and scaling of the scalp, which we called "crusted lice." This eruption differs from the well-described id reaction known as "pediculid" and represents a more dramatic manifestation of rampant infestation. This paper provides an up-to-date review of treatment options available for pediculosis humanus capitus, including newer medications like the ones that eventually led to resolution of our patient’s extreme infestation."
Source: Connor, Cody J, University of Iowa Carver College of Medicine; Broadlawns Medical Center
Selby, John C, University of Iowa Hospitals and Clinics
Wanat, Karolyn A, University of Iowa Hospitals and Clinics.
Detection of Wolbachia in Human Lice
2016 April
"Confirming the widespread presence of Wolbachia in lice would provide an immediate impetus to new approaches in the research effort to control of lice and improve the treatment of pediculosis in humans. Since it was not present in our samples, it may be that another bacterium may play the role posited for Wolbachia."
Source: Anderson, Matthew, and Eremeeva, Marina E., Georgia Southern University
Refugee crisis and re-emergence of forgotten infections in Europe
2015 December
"Makeshift shelters are becoming increasingly evident in European cities as a consequence of the momentous influx of refugees seeking asylum in European countries. These individuals have endured long, gruelling journeys to reach their target countries, often having survived appalling living conditions (Fig. 1a). One of the routes chosen by migrants is that from East Africa, through Sudan and Libya, to North Africa and eventually Europe (Fig. 1b). Not unsurprisingly, this has led to the introduction of infectious diseases that are rarely encountered in developed nations, most notably louse-borne relapsing fever (LBRF)."
Source: Cutler, Sally J. (2015) ‘Refugee crisis and re-emergence of forgotten infections in Europe’, - Clinical Microbiology and Infection.
Cytogenetic Features of Human Head and Body Lice (Phthiraptera: Pediculidae)
2015 December
"The genus Pediculus L. that parasitize humans comprise two subspecies: the head lice Pediculus humanus capitis De Geer and the body lice Pediculus humanus humanus De Geer. Despite the 200yr of the first description of these two species, there is still a long debate about their taxonomic status. Some authors proposed that these organisms are separate species, conspecifics, or grouped in clades. The sequencing of both forms indicated that the difference between them is one gene absent in the head louse. However, their chromosomal number remains to be determined. In this study, we described the male and female karyotypes, and male meiosis of head and body lice, and examined the chromatin structure by means of C-banding. In P. h. humanus and P. h. capitis, the diploid chromosome complement was 2n=12 in both sexes. In oogonial prometaphase and metaphase and spermatogonial metaphase, it is evident that chromosomes lack of a primary constriction. No identifiable sex chromosomes or B chromosomes were observed in head and body lice. Neither chiasmata nor chromatin connections between homologous chromosomes were detected in male meiosis. The meiotic behaviour of the chromosomes showed that they are holokinetic. C-banding revealed the absence of constitutive heterochromatin. Our results provide relevant information to be used in mapping studies of genes associated with sex determination and environmental sensing and response."
Source: Bressa MJ1, Papeschi AG2, Toloza AC3. - Oxford University Press on behalf of Entomological Society of America.
Head lice predictors and infestation dynamics among primary school children in Norway
2015 October
"With the exception of hair length, we have found that individual and household characteristics are of minor importance to predict head lice infestations in a low-prevalence country and that unnoticed transmissions in school classes and families are likely to be the major driver upon outbreaks."
Source: Birkemoe T, Lindstedt HH, Ottesen P, Soleng A, Næss Ø, Rukke BA. - Fam Pract. 2015 Oct 28. pii: cmv081.
A New Clade of African Body and Head Lice Infected by Bartonella quintana and Yersinia pestis-Democratic Republic of the Congo
2015 September
"The human body louse is a known vector for the transmission of three serious diseases-specifically, epidemic typhus, trench fever, and relapsing fever caused by Rickettsia prowazekii, Bartonella quintana, and Borrelia recurrentis, respectively-that have killed millions of people. It is also suspected in the transmission of a fourth pathogen, Yersinia pestis, which is the etiologic agent of plague. To date, human lice belonging to the genus Pediculus have been classified into three mitochondrial clades: A, B, and C. Here, we describe a fourth mitochondrial clade, Clade D, comprising head and body lice. Clade D may be a vector of B. quintana and Y. pestis, which is prevalent in a highly plague-endemic area near the Rethy Health District, Orientale Province, Democratic Republic of the Congo."
Source: Drali R, Shako JC, Davoust B, Diatta G, Raoult D2. - The American Society of Tropical Medicine and Hygiene. 2015 Sep 21. pii: 14-0686.
Louse-borne relapsing fever (Borrelia recurrentis) in an Eritrean refugee arriving in Switzerland
2015 August
"Here we communicate a case of louse-borne relapsing fever (LBRF) in an Eritrean refugee after arrival in Switzerland in August 2015. Borrelia recurrentis, the causative agent of LBRF, was identified by 16S rRNA gene sequencing. In addition to diagnostic and therapeutic aspects, we discuss the epidemiology of this potentially re-emerging and serious disease in the context of a recent increase in refugees from East Africa travelling to Europe."
Source: D Goldenberger, GJ Claas, C Bloch-Infanger, T Breidthardt, B Suter, M Martínez, A Neumayr, A Blaich, A Egli, M Osthof - Eurosurveillance. Vol. 20 | Weekly issue 32 | 13 August 2015.
2015 July
"Two patients from Eritrea, recently arrived in the Netherlands, presented with fever and were investigated for malaria. Bloodfilms showed spirochetes but no blood parasites. Louse-borne relapsing fever caused by Borrelia recurrentis was diagnosed. Treatment was complicated by severe Jarisch–Herxheimer reactions in both patients. Physicians should be aware of the possibility of B. recurrentis infection in migrant populations who travel under crowded conditions, especially after passing through endemic areas such as Ethiopia and neighbouring countries."
Source: K R Wilting ()1, Y Stienstra2, B Sinha1, M Braks3, D Cornish4, H Grundmann1 - Eurosurveillance, Volume 20, Issue 30, 30 July 2015.
Epidemiological comparative study of pediculosis capitis among primary school children in Fayoum and Minofiya governorates, Egypt.
2015 April
"Pediculosis is a frequent public health problem. The pattern and prevalence of Pediculosis is dependent on many socio-demographic and economic factors. It is common in schoolchildren especially primary level; it may affect their learning performance. This study aimed to determine the prevalence of head louse among primary students, in Fayoum and Bagor districts, and explore the predisposing factors of head louse infestation in both public and private schools. The study was a cross-sectional descriptive study, conducted in two governorates: Fayoum and Minofiya governorates which represent upper and lower Egypt respectively during the academic year of 2012-2013. The students were selected from different grades with a total of 10,935 students. The prevalence of head lice in the study group was 16.7 %."
Source: Abd El Raheem TA1, El Sherbiny NA, Elgameel A, El-Sayed GA, Moustafa N, Shahen S. - J Community Health. 2015 Apr;40(2):222-6. doi: 10.1007/s10900-014-9920-0.
The Distribution of Pediculus humanus capitis Among Primary School Pupils of the Turkish Chamber of Commerce and Stock Exchange Organisation in Van.
2015 March
"The infestation rates observed and the evaluation of the questionnaire showed that there is a statistically significant relationships between pediculosis capitis and sex, level of family income, education level of the mother, number of baths taken per weekly, number of family members living in the same home, room number per capita, and hair length (p<0.001). However, there was no significant relationship between pediculosis capitis and cleaning materials used to wash the head."
Source: Karaaslan S, Yılmaz H. - Turkiye Parazitol Derg 2015 Mar;39(1):27-32. doi: 10.5152/tpd.2015.3673.
Molecular survey of the head louse Pediculus humanus capitis in Thailand and its potential role for transmitting Acinetobacter spp.
2015 February
"This report is the first to describe Acinetobacter spp. in human head lice collected from school children in Thailand. The data obtained from this study might be used to develop effective planning for head louse control. The detection of pathogenic bacteria in head lice is useful for monitoring the possible head louse-borne pathogens in humans."
Source: Sakone Sunantaraporn, Vivornpun Sanprasert, Theerakamol Pengsakul, Atchara Phumee, Rungfar Boonserm, Apiwat Tawatsin, Usavadee Thavara and Padet Siriyasatien. - Parasites & Vectors 2015, 8:127.
"Collembola vs head lice: A puzzling case solved by videodermoscopy" (and it wasn’t head lice!)
2015 January
"A 65-year-old woman presented with a 4-month history of a recalcitrant pruritic scalp disorder unresponsive to repeated pediculicidal treatments. She exhibited self-collected specimens of presumed head lice entrapped in adhesive tape that she claimed to have recovered after combing her hair. At physical examination, several scratching marks were detectable on the scalp."
Source: Journal of the American Academy of Dermatology: Volume 72, Issue 1, A1-A10, S1-S78.
A ghost covered in lice: a case of severe blood loss with long-standing heavy pediculosis capitis infestation.
2014 December
"This case highlights the link between head lice (pediculosis capitis) infestation and iron-deficiency anaemia."
Source: US National Library of Medicine National Institutes of Health
Lice-borne Diseases in the Homeless Population
2014 November
"Lice were prevalent in a sample of 203 homeless people in San Francisco, as were Bartonella quintana infections, which cause trench fever, according to a recent study (Bonilla DL et al. Emerg Infect Dis. 2014;20[10]:1645-1651).

Lice are vectors of B quintana, which they transmit by excreting bacteria-laden feces onto human skin. The bacteria enter the body through mucous membranes or a louse bite. Trench fever causes symptoms such as severe headache, conjunctival congestion, lymphadenopathy, and relapsing fever, as well as potentially life-threatening endocarditis and bacillary angiomatosis. Lice also can cause pruritus, infections from scratching, and anemia. Dirty clothing and close contact with others create an ideal environment for lice infestations and transmission, making homeless people an especially vulnerable population."
Source: Journal of the American Medical Association. 2014;312(19):1962. doi:10.1001/jama.2014.14764.
Faster the better: a reliable technique to sample anopluran lice in large hosts
2014 June
"Among Anoplura, the family Echinophthiriidae includes those species that infest mainly the pinnipeds. Working with large hosts implies methodological considerations as the time spent in the sampling, and the way in that the animal is restrained. Previous works on echinophthiriids combined a diverse array of analyses including field counts of lice and in vitro observations. To collect lice, the authors used forceps, and each louse was collected individually. This implied a long manipulation time, i.e., ≈60 min and the need to physically and/or chemically immobilize the animal. The present work described and discussed for the first a sample technique that minimized the manipulation time and also avoiding the use of anesthesia. This methodology implied combing the host's pelage with a fine-tooth plastic comb, as used in the treatment of human pediculosis, and keeping the comb with the lice retained in a Ziploc® bag with ethanol. This technique was used successfully in studies of population dynamic, habitat selection, and transmission pattern, being a reliable methodology. Lice are collected entirely and are in a good condition to prepare them for mounting for studying under light or scanning electron microscopy. Moreover, the use of the plastic comb protects from damaging taxonomically important structures as spines being also recommended to reach taxonomic or morphological goals."
Source: Laboratorio de Parasitología, Centro Nacional Patagónico, CENPAT-CONICET, Boulevard Brown 2915, PC U9120ACV, Puerto Madryn, Argentina, Parasitol Res. 2014 Jun;113(6):2015-8. doi: 10.1007/s00436-014-3890-0. Epub 2014 Apr 22.
[Epidemiological study of Pediculosis in elementary schools of Arica, northern Chile]
2014 June
"Pediculosis is an ectoparasitosis infestation that has not received much attention in northern Chile despite it is a common reoccurring condition among school-age children. The objective of this study is to determine the prevalence of Pediculus humanus capitis infestation in elementary schools of Arica... The school population of Arica is significantly affected by Pediculosis and its prevalence is similar to other regions."
Source: Gazmuri B P, Arriaza T B, Castro S F, González N P, Maripan V K, Saavedra R I. Rev Chil Pediatr. 2014 Jun;85(3):312-8. doi: 10.4067/S0370-41062014000300007.
(Letter) Bartonella quintana in Body Lice from Scalp Hair of Homeless Persons, France
2014 May
"Bartonella quintana is a body louse–borne human pathogen that can cause trench fever, bacillary angiomatosis, endocarditis, chronic bacteremia, and chronic lymphadenopathy (1). Recently, B. quintana DNA was detected in lice collected from the heads of poor and homeless persons from the United States, Nepal, Senegal, Ethiopia, and the Democratic Republic of the Congo and in nits in France (2,3)."
Source: Rezak Drali, Abdoul Karim Sangaré, Amina Boutellis, Emmanouil Angelakis, Aurélie Veracx, Cristina Socolovschi, Philippe Brouqui, and Didier Raoult. Emerging Infectious Diseases. Volume 20, Number 5—May 2014.
Differential gene expression in laboratory strains of human head and body lice when challenged with Bartonella quintana, a pathogenic bacterium
2014 April
"Human head and body lice are obligatory hematophagous ectoparasites that belong to a single species, Pediculus humanus. Only body lice, however, are vectors of the infectious Gram-negative bacterium Bartonella quintana. Because of their near identical genomes, yet differential vector competence, head and body lice provide a unique model system to study the gain or loss of vector competence. Using our in vitro louse-rearing system, we infected head and body lice with blood containing B. quintana in order to detect both differences in the proliferation of B. quintana and transcriptional differences of immune-related genes in the lice. B. quintana proliferated rapidly in body lice at 6 days postinfection, but plateaued in head lice at 4 days postinfection. RNAseq and quantitative real-time PCR validation analyses determined gene expression differences. Eight immunoresponse genes were observed to be significantly different with many associated with the Toll pathway: Fibrinogen-like protein, Spaetzle, Defensin 1, Serpin, Scavenger receptor A and Apolipoporhrin 2. Our findings support the hypothesis that body lice, unlike head lice, fight infection from B. quintana only at the later stages of its proliferation."
Source: D. Previte, B. P. Olds, K. Yoon, W. Sun, W. Muir, K. N. Paige, S. H. Lee. Insect Mol Biol. 2014 April ; 23(2): 244–254. doi:10.1111/imb.12077..
Drought and epidemic typhus, central Mexico, 1655-1918
2014 March
"Epidemic typhus is an infectious disease caused by the bacterium Rickettsia prowazekii and transmitted by body lice (Pediculus humanus corporis). This disease occurs where conditions are crowded and unsanitary. This disease accompanied war, famine, and poverty for centuries. Historical and proxy climate data indicate that drought was a major factor in the development of typhus epidemics in Mexico during 1655-1918. Evidence was found for 22 large typhus epidemics in central Mexico, and tree-ring chronologies were used to reconstruct moisture levels over central Mexico for the past 500 years. Below-average tree growth, reconstructed drought, and low crop yields occurred during 19 of these 22 typhus epidemics. Historical documents describe how drought created large numbers of environmental refugees that fled the famine-stricken countryside for food relief in towns. These refugees often ended up in improvised shelters in which crowding encouraged conditions necessary for spread of typhus. KEYWORDS: Mexico; Pediculus humanus corporis; Rickettsia prowazekii; bacteria; body lice; drought; epidemics; tree rings; typhus."
Source: Burns JN, Acuna-Soto R, Stahle DW. PMID: 24564928 PMCID: PMC3944858 DOI: 10.3201/eid2003.131366.
The biology and taxonomy of head and body lice-implications for louse-borne disease prevention
2013 Nov
"ABSTRACT: Sucking lice (Phthiraptera: Anoplura) are obligate blood-feeding ectoparasites of placental mammals including humans. Worldwide, more than 550 species have been described and many are specific to a particular host species of mammal [1]. Three taxa uniquely parasitize humans: the head louse, body louse, and crab (pubic) louse. The body louse, in particular, has epidemiological importance because it is a vector of the causative agents of three important human diseases: epidemic typhus, trench fever, and louse-borne relapsing fever. Since the advent of antibiotics and more effective body louse control measures in the 1940s, these diseases have markedly diminished in incidence. However, due to 1) increasing pediculicide resistance in human lice, 2) reemergence of body louse populations in some geographic areas and demographic groups, 3) persistent head louse infestations, and 4) recent detection of body louse-borne pathogens in head lice, lice and louse-borne diseases are an emerging problem worldwide. This mini-review is focused on human body and head lice including their biological relationship to each other and its epidemiological relevance, the status and treatment of human louse-borne diseases, and current approaches to prevention and control of human louse infestations."
Source: Denise L Bonilla, Lance A Durden, Marina E Eremeeva, Gregory A Dasch Vector-Borne Disease Section, California Department of Public Health, Richmond, California, United States of America. PLoS Pathogens (Impact Factor: 8.14). 11/2013; 9(11):e1003724. DOI:10.1371/journal.ppat.1003724. PubMed. 2013 May.
Borrelia recurrentis in Head Lice, Ethiopia
2013 May
"Since the 1800s, the only known vector of Borrelia recurrentis has been the body louse. In 2011, we found B. recurrentis DNA in 23% of head lice from patients with louse-borne relapsing fever in Ethiopia."
Source: Boutellis A, Mediannikov O, Bilcha KD, Ali J, Campelo D, Barker SC, et al. "Borrelia recurrentis in head lice, Ethiopia." Emerg Infect Dis. 2013 May.
Plague Epidemics and Lice, Democratic Republic of the Congo
2013 Mar
"Our detection of B. quintana and the plague agent Y. pestis in modern head and body lice is similar to findings of a paleomicrobiological investigation at a medieval plague site near Paris."
Source: Centers for Disease Control and Prevention
UP kids’ killer disease spread through lice, expert panel finds
2013 Mar
"The mystery deaths of hundreds of children in eastern Uttar Pradesh last year was likely caused by a bacterial infection that is transmitted through head lice, an expert group has concluded."
Source: The Indian Express
Distinguishing body lice from head lice by multiplex real-time PCR analysis of the Phum_PHUM540560 gene
2013 Feb
"Body louse or head louse? Once removed from their environment, body and head lice are indistinguishable. Neither the morphological criteria used since the mid-18th century nor the various genetic studies conducted since the advent of molecular biology tools have allowed body lice and head lice to be differentiated. In this work, using a portion of the Phum_PHUM540560 gene from the body louse, we aimed to develop a multiplex real-time polymerase chain reaction (PCR) assay to differentiate between body and head lice in a single reaction."
Source: Drali R, Boutellis A, Raoult D, Rolain JM, Brouqui P.
PLoS One. 2013;8(2):e58088. doi: 10.1371/journal.pone.0058088. Epub 2013 Feb 28.
First report of family infestation with pubic louse (Pthirus pubis; Insecta: Anoplura: Pthiridae) in Iran – a case report
2013 Jan
"The sucking lice including the head, body and pubic louse infest humans and so they are of high hygienic importance. Pubic lice are transmitted during sexual contact in adults. Thus, infestation of children with pubis louse is very rare. A case of infestation with pubic louse (Pthirus pubis) in a family in Kashan was seen. On examination of family members, the parasites were collected and observed under the light microscope. Infestation of eyelashes with P. pubis lice was confirmed. Since this parasite can be observed on the skin, infestation with this louse has always been one of the concerns of human communities. Pthiriasis has frequently been reported in many parts of the world; however, there are few reports on this infestation in Iran, especially familial infestation with this louse. Hence, this article could be the first report on the familial infestation with P. pubis in Iran and it can be suggested that infestation with pubic lice occurs in sporadic form in all over the country"
Source: Dehghani, R., Limoee, M. and Ahaki, A.R.3
Tropical Biomedicine 30(1): 152–154 (2013)
The origin and distribution of human lice in the world
"Two genera of lice parasitize humans: Pthirus and Pediculus. The latter is of significant public health importance and comprises two ecotypes: the body louse and the head louse."
Source: Amina Boutellisa, Laurent Abi-Rachedb, Didier Raoulta.
Neurological Manifestations of Bartonellosis in Immunocompetent Patients: A Composite of Reports from 2005-2012
"It is important that the medical history include questions related to arthropod (lice, fleas, and ticks) and animal exposures."
Source: Journal of Neuroparasitology - Vol. 3 (2012), Article ID 235640, 15 pages - doi:10.4303/jnp/235640
E. B. Breitschwerdt,1 S. Sontakke,1,2 and S. Hopkins.
Evidence That Head and Body Lice on Homeless Persons Have the Same Genotype
"These findings confirm that head and body lice are two ecotypes of the same species and show the importance of implementing measures to prevent lice transmission between homeless people in shelters."
Source: Aurélie Veracx, Romain Rivet, Karen D. McCoy, Philippe Brouqui, Didier Raoult
Evidence for an African cluster of human head and body lice with variable colors and interbreeding of lice between continents.
2012 May
"We identified two geotypes of Clade A head and body lice including one that is specifically African, that can be either black or grey and can live on the head or in clothing. We also hypothesized that lice from different areas are interbreeding"
Source: PLoS One. 2012;7(5):e37804. doi: 10.1371/journal.pone.0037804. Epub 2012 May 25.
"Evidence for an African cluster of human head and body lice with variable colors and interbreeding of lice between continents." Veracx A1, Boutellis A, Merhej V, Diatta G, Raoult D.
Bartonella quintana in head lice from Sénégal.
2012 May
"Head and body lice are strict, obligate human ectoparasites with three mitochondrial clades (A, B, and C). Body lice have been implicated as vectors of human diseases, and as the principal vectors of epidemic typhus, relapsing fever, and Bartonella quintata-associated diseases (trench fever, bacillary angiomatosis, endocarditis, chronic bacteremia, and chronic lymphadenopathy). Using molecular methods (real-time and traditional PCR), we assessed the presence of Bartonella quintana DNA in black head lice collected from three locations in Sénégal. DNA from B. quintana was identified in 19 lice (6.93%) collected from 7 patients (7%) in Dakar. B. quintana-positive lice collected from three subjects were identified as clades C and A."
Source: Vector Borne Zoonotic Dis. 2012 Jul;12(7):564-7. doi: 10.1089/vbz.2011.0845.
Boutellis A, Veracx A, Angelakis E, Diatta G, Mediannikov O, Trape JF, Raoult D.
Université de la Méditerranée, Faculté de Médecine, Marseille, France.
Mapping the social network: tracking lice in a wild primate (Microcebus rufus) population to infer social contacts and vector potential
2012 March
"Using a simple method, we were able to visualize exchanges of lice in a population of cryptic wild primates. This method not only provided insight into the previously unseen parasite movement between lemurs, but also allowed us to infer social interactions between them. As lice are known pathogen vectors, our method also allowed us to identify the lemurs most likely to facilitate louse-mediated epidemics. Our approach demonstrates the potential to uncover otherwise inaccessible parasite-host, and host social interaction data in any trappable species parasitized by sucking lice."
NPA Note: These aren’t human head lice but it is trail-blazing and provides insights and relevance to human lice and disease. Source: BMC Ecology
Sarah Zohdy, Addison D Kemp, Lance A Durden, Patricia C Wright and Jukka Jernvall
Bartonella quintana in Ethiopian lice.
2012 March
"The finding of B. quintana among head lice is important given the frequency of infestations seen among humans, especially children, around the globe. The perception among the general public is that head lice do not carry pathogens, a belief that should now be rectified. Whether all genetic lineages of head lice are equally competent for this pathogen under natural circumstances remains to be elucidated by comprehensive studies of head lice from diverse locations."
Source: Community-acquired infections
S. Cutler* (London, GB)
Human louse-transmitted infectious diseases.
2012 January
"Several of the infectious diseases associated with human lice are life-threatening, including epidemic typhus, relapsing fever, and trench fever, which are caused by Rickettsia prowazekii, Borrelia recurrentis, and Bartonella quintana, respectively. Although these diseases have been known for several centuries, they remain a major public health concern in populations living in poor-hygiene conditions because of war, social disruption, severe poverty, or gaps in public health management. Poor-hygiene conditions favour a higher prevalence of body lice, which are the main vectors for these diseases. Trench fever has been reported in both developing and developed countries in populations living in poor conditions, such as homeless individuals. In contrast, outbreaks of epidemic typhus and epidemic relapsing fever have occurred in jails and refugee camps in developing countries. However, reports of a significantly high seroprevalence for epidemic typhus and epidemic relapsing fever in the homeless populations of developed countries suggest that these populations remain at high risk for outbreaks of these diseases. Additionally, experimental laboratory studies have demonstrated that the body louse can transmit other emerging or re-emerging pathogens, such as Acinetobacter baumannii and Yersinia pestis. Therefore, a strict survey of louse-borne diseases and the implementation of efficient delousing strategies in these populations should be public health priorities."
Source: Clinical Microbiology and Infection 2012 - European Society of Clinical Microbiology and Infectious Diseases, CMI, 18, 332–337.
S. Badiaga, and P. Brouqui
Brill-Zinsser Disease in Moroccan Man, France, 2011
2011 December
"Epidemic typhus is caused by Rickettsia prowazekii and transmitted by human body lice. For centuries, it has been associated with overcrowding, cold weather, and poor hygiene. Brill-Zinsser disease is a recurrent form of epidemic typhus that is unrelated to louse infestation and develops sporadically years after the primary illness."
Source: Faucher JF, Socolovschi C, Aubry C, Chirouze C, Hustache-Mathieu L, Raoult D, et al. "Brill-Zinsser disease in Moroccan man, France, 2011" [letter]. Emerg Infect Dis, 2012 Jan.
Detection of Acinetobacter baumannii in head lice from elementary schoolchildren in Paris
2011 December
"The human body louse is the only known vector of Bartonella quintana. However, the presence of this bacterium has recently been detected in the head lice of homeless individuals and Nepalese slum children. Previous studies have reported the isolation of Acinetobacter baumannii from the body lice of homeless individuals. An epidemiological survey including 74 schools was conducted between 2008 and 2009 in Paris. After a first visual examination, the hair of children with suspected pediculosis was combed with a fine-tooth comb to collect live adult head lice. Molecular studies were performed on randomly selected DNA samples to detect B. quintana and A. baumannii by specific quantitative real-time PCR. Among a collection of 288 DNA samples, B. quintana was not detected, but A. baumannii was detected in 95 DNA samples (33%). Further study is needed to determine the significance of the finding of A. baumannii in head lice."
Source: Comp Immunol Microbiol Infect Dis. 2011 Dec;34(6):475-7. doi: 10.1016/j.cimid.2011.08.007. Epub 2011 Oct 5.
Université Paris-Est Créteil Val de Marne and Department of Dermatology, Hospital Henri Mondor, 51, avenue du Maréchal de Lattre de Tassigny, 94010 Créteil, France.
Bouvresse S, Socolovshi C, Berdjane Z, Durand R, Izri A, Raoult D, Chosidow O, Brouqui P.
Severe iron deficiency anemia and lice infestation
2011 October
"This is the first published evidence of a provocative association of louse infestation and severe iron deficiency anemia in humans."
Source: J Emerg Med. 2011 Oct;41(4):362-5. doi: 10.1016/j.jemermed.2010.05.030. Epub 2010 Jul 24.
Altitude-dependent Bartonella quintana genotype C in head lice, Ethiopia.
2011 December
"To determine the presence of Bartonella quintana in head and body lice from persons in different locations in Ethiopia, we used molecular methods. B. quintana was found in 19 (7%) genotype C head lice and in 76 (18%) genotype A body lice. B. quintana in head lice was positively linked to altitude (p = 0.014)."
Source: Université de la Méditerranée, Marseille, France.
Angelakis E, Diatta G, Abdissa A, Trape JF, Mediannikov O, Richet H, Raoult D.
Bartonella quintana in Ethiopian lice.
2011 October
"The higher numbers of infected head lice pools compared with clothing lice suggests their competence for maintaining this infection within Ethiopia."
Source: Comp Immunol Microbiol Infect Dis 2011 Oct 21.
Cutler S, Abdissa A, Adamu H, Tolosa T, Gashaw A.
Bartonellosis: A hidden epidemic.
"Physicians should be educated as to the large number of Bartonella spp. in nature, the extensive spectrum of animal reservoir hosts, the diversity of confirmed and potential arthropod vectors, current limitations associated with diagnosis and treatment efficacy, and the ecological and evolving medical complexity of these highly evolved bacteria."
Source: Bayer Animal Health Symposium.
Edward B. Breitschwerdt, DVM, DACVIM.
Bartonella quintana in head louse nits.
2011 July
"Bartonella quintana DNA has been detected exclusively in head lice collected from impoverished populations such as the homeless or Nepalese children living in slums or on the streets, who are usually infested by both head and body lice. ...the role of the head louse in the maintenance and transmission of B. quintana remains to be determined."
Source: FEMS Immunology & Medical Microbiology Volume 62, Issue 2, pages 244-246, July 2011
Emmanouil Angelakis, Jean-Marc Rolain, Didier Raoult, Philippe Brouqui.
Evidence of a louse-borne outbreak involving typhus in Douai, 1710-1712 during the war of Spanish succession.
Anaemia due to head lice is unlikely, in an otherwise healthy child. However untreated, prolonged and severe infestation might lead to anaemia in the long term.
Source: Nguyen-Hieu T1, Aboudharam G, Signoli M, Rigeade C, Drancourt M, Raoult D. PLoS One. 2010 Oct 27;5(10):e15405. doi: 10.1371/journal.pone.0015405. (2010)
Human Pediculosis and Anaemia: A "Lousy" Association
Anaemia due to head lice is unlikely, in an otherwise healthy child. However untreated, prolonged and severe infestation might lead to anaemia in the long term.
Source: Pediatric Research (2010) 68, 636–636; doi:10.1203/00006450-201011001-01284.
Genotyping of Human Lice Suggests Multiple Emergences of Body Lice from Local Head Louse Populations
2010 March
While being phenotypically and physiologically different, human head and body lice are indistinguishable based on mitochondrial and nuclear genes. As protein-coding genes are too conserved to provide significant genetic diversity, we performed strain-typing of a large collection of human head and body lice using variable intergenic spacer sequences.
Rickettsial infections: Indian perspective
2010 March
Underdiagnosed and misdiagnosed rickettsial infections are important public health problems. They also lead to extensive investigations in children with fever of undetermined origin contributing to financial burden on families. The present review addresses the epidemiology, clinical features, diagnosis and management issues of these infections, primarily for a practicing clinician.
Source: Narendra Rathi, Akanksha Rathi. Indian Pediatrics. Volume 47, Issue 2, pp 157-164.
Body lice originate from head lice
2010 March
Until now, head lice and body lice were thought to be different species.
Beyond Anthrax: The Weaponization of Infectious Diseases Section 8.2.3
"Of the 3,000 or so species of lice that have been characterized, only three are strictly human parasites, the clothing or body louse, P. humanus humanus; the head louse, P. humanus capitus; and the crab or pubic louse, Pthrius pubis."
Epidemiology of Pediculosis capitis in elementary schools of Buenos Aires, Argentina.
2009 June
"The infestation with the human obligate ectoparasite Pediculus humanus capitis De Geer is a common public health problem affecting mainly schoolchildren worldwide. The aim of the present study was to investigate the infestation levels of head lice in elementary schools from Buenos Aires with resistant levels to permethrin >100. A total of 1,856 children aged 3-13 years old from eight selected elementary schools were examined for head lice. Pediculosis was observed in all the studied schools. The overall infestation rate was 29.7%. Girls were statistically significant more infested than boys, with infestation rate values of 36.1% and 26.7%, respectively (P < 0.0001). Only 42 of the infested girls (12%) and 23 of the infested boys (11.4%) had >10 lice on their hair. The proportions of infested children-both girls and boys-in each age group were not found to differ significantly from one another. The infestation rate among schools varied from 19.12% to 42.74%. This indicated that pediculosis is relatively common in elementary schools from Buenos Aires, and those levels are of epidemic importance. The differences of pediculosis among the studied schools could be explained by the different control strategies applied by parents or advisors to eradicate head lice."
Source: Toloza A1, Vassena C, Gallardo A, González-Audino P, Picollo MI. Parasitol Res. 2009 Jun;104(6):1295-8. doi: 10.1007/s00436-008-1324-6. Epub 2009 Jan 16.
Louse- and flea-borne rickettsioses: biological and genomic analyses
Source: Vet Res. 2009 Mar-Apr; 40(2): 12. Joseph J. Gillespie, Nicole C. Ammerman, [...], and Abdu F. Azad
Bartonella quintana in Body Lice and Head Lice from Homeless Persons, San Francisco, California, USA
June 2009
Epidermal parasitic skin diseases: a neglected category of poverty-associated plagues.
2009 February - World Health Organization - by Hermann Feldmeier & Jorg Heukelbach

"Epidermal parasitic skin diseases (EPSD) occur worldwide and have been known since ancient times. Despite the considerable burden caused by EPSD, this category of parasitic diseases has been widely neglected by the scientific community and health-care providers. This is illustrated by the fact that in the recent edition of The Communicable disease control handbook, a reference manual for public health interventions, only one EPSD (scabies) is mentioned. EPSD fulfil the criteria defined by Ehrenberg & Ault (2005) for neglected diseases of neglected populations, but are not listed on national or international agendas concerning disease control priorities. This probably explains why efforts to control EPSD at the community level have very rarely been undertaken.

"Six EPSD are of particular importance: scabies, pediculosis (head lice, body lice and pubic lice infestation), tungiasis (sand flea disease) and hookworm-related cutaneous larva migrans (HrCLM). They are either prevalent in resource-poor settings or are associated with important morbidity. In this paper we focus on these diseases, summarize the existing knowledge on the epidemiology and the morbidity in resource-poor settings and focus on the interactions between EPSD and poverty."

Apes, lice and prehistory
2009 by Robin A Weiss
Preventing and Controlling Emerging and Reemerging Transmissible Diseases in the Homeless.
2008 September
"Snapshot interventions have also identified the risk for the homeless of acquiring other louse-borne diseases such as epidemic typhus and relapsing fever, and enabled the first isolation of A. baumanii from lice (5,32,39)."
Source: Emerging Infectious Diseases Vol. 14, No. 9, September 2008
Emerging and re-emerging rickettsioses: endothelial cell infection and early disease events.
2008 Walker DH, Ismail N.
Headlice: a precursor to Group A Streptococcal infection in remove Indigenous children.
2007 November - Head Lice

"Indigenous children living in remote Australia are suffering from infections with sequelae that are causing devastating effects that will continue into adulthood. Impetigo, also known as school sores, is a contagious, superficial pyogenic skin infection; the causative organism is commonly Group A beta-haemolytic streptococci (GAS) also known as Streptococcus pyogenes1. GAS infections have been reported to be endemic in some Northern Territory communities, with 70% of children having impetigo as a result of infected scabies and other infestation lesions2.

A known post-infection sequelae of GAS is rheumatic heart disease; GAS is also believed to contribute to adult renal disease subsequent to post streptococcal glomerular nephritis2. Because of this prevention, early detection and aggressive management of skin infections experienced by remote Indigenous children is essential. An understanding the social determinates of health is also needed to provide comprehensive care for Indigenous children. This case study will describe the care of a small Indigenous child suffering from impetigo secondary to head louse infestation."

Feces of Pediculus capitis humanus as sign of viability of the louse.
2007 April
"When viable lice are not visible on the hair, to find on the hair species specific feces can indirectly confirm their existence. The feces can be barely visible to the naked eye as blackish dots. On the other hand, they can be more easily put in evidence by the dermosco- pe used with dry technique. The most typical appearance of the louse feces discharged from a short time is that of dark clustered globules, fixed to the hair or free on the surface of the scalp."

Images below appear with permission from Dr. Gaetano Scanni

Pediculus & Feces

Dr. Gaetano Scanni

Pediculus & Feces

Dr. Gaetano Scanni

Pediculus & Feces

Dr. Gaetano Scanni

Supergroup F. Wolbachia bacteria parasitise lice.
2007 March
"This is first report of an infection of supergroup F. Wolbachia in lice."
First Molecular Evidence of Bartonella quintana in Pediculus humanus
capitis (Phthiraptera: Pediculidae), Collected from Nepalese children

“B. quintana DNA sequences were detected in both head and body lice from two children as well as in body lice derived from two other children. These results demonstrate that head lice may also play a role in the transmission of trench fever.”
Toshinori Sasaki; Shree Kanta S. Poudel; Haruhiko Isawa; Toshihiko Hayashi; Naomi Seki; Takashi Tomita; Kyoko Sawabe; Mutsuo Kobayashi
Quantification of blood intake of the head louse: Pediculus humanus capitis.
May 2006
"Although head lice, Pediculus humanus capitis, are globally prevalent blood-sucking ectoparasites, the amount of blood imbibed by head lice has not been determined. This study investigated this parameter, as regular loss of a small quantity of blood may lead to an iron deficiency and anaemia. Adult female lice (66), adult males (46), and nymphs (152) were weighed before and after feeding in groups of 17-109 lice. The average amounts of blood imbibed at a single feed were: adult female louse (0.0001579 ml), adult male (0.0000657 ml) and nymph (0.0000387 ml). Assuming three feeds per day by an average infection of 30 lice (10 females, 10 males, and 10 nymphs), the average child with active pediculosis would loose 0.008 ml of blood per day. This amount of blood loss is of no clinical significance even in iron-deficient children. The most heavily infected child observed with 2657 lice could be expected to loose 0.7 ml/day or 20.8 ml/month, which may be of clinical importance in a child on an adequate diet, and would be significant in an iron-deficient child. However, if head lice feed more often than three times a day, a heavy infestation would have a greater potential to lead to iron deficiency. The frequency of feeding of head lice on the head of the human host needs to be determined."
Speare R1, Canyon DV, Melrose W. Int J Dermatol. 2006 May;45(5):543-6.
Transmission potential of the human head louse, Pediculus capitis (Anoplura: Pediculidae).
October 2005
"Adult lice were the most likely to disperse. Neither population density nor hunger significantly affected dispersal tendencies. Lice were dislodged by air movement, combs and towels, and passively transferred to fabric within 5 min. Females oviposited on a variety of substrates and 59% of eggs incubated for 8 h/night hatched after 14-16 days. There was no survivorship difference between lice artificially fed on female vs. male blood... Adult lice are the most mobile, indicating that they are most likely to initiate new infestations. Although head-to-head contact may be the primary route of transmission, less direct routes involving fomites may play a role and need further evaluation. Blood-borne factors do not appear to cause any gender-biased host preference."
Takano-Lee M, Edman JD, Mullens BA, Clark JM. Int J Dermatol. 2005 Oct;44(10):811-6.
Symbiotic Bacteria Associated with Stomach Discs of Human Lice †
2006, September
The symbiotic bacteria associated with the stomach disc, a large aggregate of bacteriocytes on the ventral side of the midgut, of human body and head lice were characterized. Molecular phylogenetic analysis of 16S rRNA gene sequences showed that the symbionts formed a distinct and well-defined clade in the Gammaproteobacteria. >>>
Multispacer typing of Rickettsia prowazekii enabling epidemiological studies of epidemic typhus.
September 2005
"Currently, there is no tool for typing Rickettsia prowazekii, the causative agent of epidemic typhus, currently considered a potential bioterrorism agent, at the strain level."
Zhu Y, Fournier PE, Ogata H, Raoult D.
Excretion of living Borrelia recurrentis in feces of infected human body lice.
2005 June
"We conclude that, similar to epidemic typhus and trench fever, transmission of LBRF may be caused by lice feces."

Houhamdi L, Raoult D.
Drugs used in treatment of pediculosis
2005 March
"This having been said, the two are so closely related that it is naive to believe that head lice will never be shown to spread disease."
Elston DM.
Lice and lice-borne diseases in humans
2005 March
Rickettsia prowazekii, Borrelia recurrentis, Bartonella quintana, Acinetobacter baumannii

Houhamdi L, Parola P, Raoult D.
Ectoparasitism and vector-borne diseases in 930 homeless people in Marseilles
2005 January
"The uncontrolled louse infestation of this population should alert the community to the possibility of severe re-emerging louse-borne infections."
Brouqui P, Stein A, Dupont HT, Gallian P, Badiaga S, Rolain JM, Mege JL, La Scola B, Berbis P, Raoult D.
On the ubiquity and phylogeny of Wolbachia in lice
2004 November
"Here we document the apparent ubiquity and diversity of Wolbachia in the insect orders Anoplura (sucking lice) and Mallophaga (chewing lice), by detecting single or multiple infections in each of 25 tested populations of lice."
Louse-borne human pathogen Bartella quintana is a genomic derivative of the zoonotic agent Bartonella henselae
2004 February
Cecilia M. Alsmark * {dagger}{ddagger}, A. Carolin Frank * {dagger}, E. Olof Karlberg * {dagger}, Boris-Antoine Legault *, David H. Ardell * §, Björn Canbäck * ¶, Ann-Sofie Eriksson *, A. Kristina Näslund *, Scott A. Handley * ||, Maxime Huvet *, Bernard La Scola * **, Martin Holmberg {dagger}{dagger} and Siv G. E. Andersson *, {ddagger}{ddagger}
Potential role of head lice, Pediculus humanus capitis, as vectors of Rickettsia prowazekii.
2003 June
"This review of the epidemiology of head louse and body louse infestations, and of LBET, indicates that head lice are potential vectors of R. prowazekii in the field."
Robinson D, Leo N, Prociv P, Barker SC.
Head Lice and body lice: (pdf) 2003 May
shared traits invalidate assumptions about evolutionary and medical distinctions
Bartonella quintana Bacteremia Among Homeless People
C. Foucault, K. Barrau, P. Brouqui, and D. Raoult
Human Pathogens in Body and Head Lice
2002 November
Pierre-Edouard Fournier,* Jean-Bosco Ndihokubwayo,*† Jo Guidran,‡ Patrick J. Kelly,§ and Didier Raoult*
Detection of Rickettsia prowazekii in Body Lice and Their Feces by Using Monoclonal Antibodies
2002 September
Rong Fang, Linda Houhamdi and Didier Raoult*
Detection of Bartonella quintana from body lice (Anoplura: Pediculidae) infesting homeless people in Tokyo by molecular technique.
2002 May
Sasaki T, Kobayashi M, Agui N.
Experimental Model of Human Body Louse Infection Using Green Fluorescent Protein-Expressing Bartonella quintana
2001 March
Pierre-Edouard Fournier,1 Michael F. Minnick,2 Hubert Lepidi,1,3 Eric Salvo,1 and Didier Raoult1,*
Serodiagnosis of Louse-Borne Relapsing Fever with Glycerophophodiester Phosphodiesterase (GlpQ) from Borrelia recurrentis
2000 October

Stephen F. Porcella,1 Sandra J. Raffel,1 Merry E. Schrumpf,1 Martin E. Schriefer,2 David T. Dennis,2 and Tom G. Schwan1,*
The body louse as a vector for reemerging human diseases
1999 October

Raoult D, Roux V.
Rickettsial Pathogens and Their Arthropod Vectors

Source: [Emerging Infectious Diseases] [Volume 4 No. 2 / April - June 1998]. Abdu F. Azad* and Charles B. Beard†.
*University of Maryland School of Medicine, Baltimore, Maryland, USA; and †Centers for Disease Control and Prevention, Atlanta, Georgia, USA
The neglected saliva: medically important toxins in the saliva of human lice

D. Jones
Seroprevalence to Bartonella quintana among patients at a community clinic in downtown Seattle
1996 April
Jackson LA, Spach DH, Kippen DA, Sugg NK, Regnery RL, Sayers MH, Stamm WE.
Body Lice as Tools for Diagnosis and Surveillance of Reemerging Diseases
1999 March
Veronique Roux and Didier Raoult*
Emergence of Bartonella quintana Infection among Homeless Persons
Emerging Infectious Diseases * Volume 2 * Number 2            April-June 1996
Head lice as vectors of disease
L. Lance Sholdt, PhD
Disease Vector Ecology Profile
1994 September
Armed Forces Pest Management Board

Report to the Department of Defense - Armed Forces Pest Management Board
1992 Deborah Z. Altschuler

Zinsser, Lice And History
1990 Deborah Z. Altschuler
Progress, National Pediculosis Association

Phoretic relationships between sucking lice (Anoplura) and flies (Diptera) associated with humans and livestock
1990 L. A. Durden
The Entomologist - 109

National Committee to Abolish Nit-Picking and 'Fine-Tooth Combing'
1980 Unsigned Letter
Pediatrics. Vol. 65, No. 2, 1980.

May 1971 - Benjamin Ken and John H. Poorbaugh, Ph.D.
Infection of Head Lice with Rickettsia Prowazeki
May 1966 - U.S. Army Biological Laboratories
The Louse
Two chapters of a true classic.
Nobel Prize Speech on Typhus and the Louse
1928 Charles Nicolle
"The contagious agent was therefore something attached to his skin and clothing, something which soap and water could remove. It could only be the louse. It was the louse."

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