Table of Contents — Volume 23, Number 4—April Please use the form below to submit correspondence to the authors or contact them at the following address:. Highlight and copy the desired format. Section Navigation. Article Metrics. Ronnie Henry. Figure Figure. Philadelphia: Elsevier Saunders; Thirty-seven human cases of sparganosis from Ethiopia and South Sudan caused by Spirometra spp.
Am J Trop Med Hyg. DOI PubMed.
The animal parasites of man. New York: William Wood and Company; Other cestodes: sparganosis, coenurosis and Taenia crassiceps cysticercosis. Handb Clin Neurol. Comments character s remaining. Comment submitted successfully, thank you for your feedback. Page created: March 17, The commonest skin disorder was pediculosis Almost one-fourth of the study participants Over one-third The prevalence of skin disorders was significantly high among females 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. Louse-borne relapsing fever Borrelia recurrentis infection. An endemic focus persists in Ethiopia and adjacent territories in the Horn of Africa. Since , 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.
Transmission is confined to the human body louse Pediculus humanus corporis, and, perhaps, the head louse P. Infection is by inoculation of louse coelomic fluid or faeces by scratching. Nosocomial infections are possible from contamination by infected blood. 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, days after infection.
Epidemiol Infect. 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. J Parasitol.
Crowded boarding houses and church dwellings in Ethiopia are analogous to the crowded air-raid shelters of World War II. 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.
Barker and Dayana Barker. Emerging Infectious Diseases. Res Rep Trop Med. The new classification confirmed and supplemented the previously constructed one by determining the position of Rickettsia africae str. ESF-5, R. OSU , R. Khabarovsk, R. 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. Shpynov, P. Fournier, N. Pozdnichenko, A. Gumenuk3 and A. New Microbes and New Infections. Volume 23, May , Pages 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.
Comparative head lice samples collected from indigenous population of schoolchildren non-immigrant were also analyzed to frame the study. 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. 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.
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. 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. 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.
Rickettsiae from the infected feces enter the skin via abrasions or bite site and access the human host. Akram; Vidhya Prakash. 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 head lice, collected from individuals, belonged to clade E, specific to West Africa.
Bartonella quintana, the causative agent of trench fever, was identified in three of the 0. 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 MI-TI-LF 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.
The mechanisms by which body lice became a vector for B.
Following oral challenge, green fluorescent protein-expressing B. Lice depend on bacteria to supply essential vitamins missing from blood, their only food source. This social stigma reaches many of the estimated 14 million people who are annually infested in the U. However, these blood sucking lice have had a long and complex evolutionary history tied to humans and other mammals. In total, there are species of blood sucking lice and each species parasitizes one or just a few mammal species. 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. 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. This study is also the first to report the presence of DNAs of B. Further studies are needed to determine whether the head lice can transmit these pathogenic bacteria from person to another. Dtsch Arztebl Int. 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.
The Royal Society for Public Health. 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.
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.
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. Microbiol Spectr. An outbreak of pubic louse infestation on the scalp hair of elderly women.
J Eur Acad Dermatol Venereol. 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]. Although many treatment options are available, lice are becoming more resistant to conventional therapies and severe clinical presentations are bound to become more prevalent.
Since it was not present in our samples, it may be that another bacterium may play the role posited for Wolbachia. These individuals have endured long, gruelling journeys to reach their target countries, often having survived appalling living conditions Fig.
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. Despite the yr 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 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. 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. 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. 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. Epidemiological comparative study of pediculosis capitis among primary school children in Fayoum and Minofiya governorates, Egypt. 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 The students were selected from different grades with a total of 10, students.
The prevalence of head lice in the study group was However, there was no significant relationship between pediculosis capitis and cleaning materials used to wash the head. Molecular survey of the head louse Pediculus humanus capitis in Thailand and its potential role for transmitting Acinetobacter spp. 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. 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. A ghost covered in lice: a case of severe blood loss with long-standing heavy pediculosis capitis infestation. Emerg Infect Dis. 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.
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. 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 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.
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Parasitol Res. Epub Apr 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. Rev Chil Pediatr. Recently, B. Volume 20, Number 5—May 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. 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. Previte, B.
Olds, K. Yoon, W. Sun, W. Muir, K.
Paige, S. Insect Mol Biol.
Volume 14, Number 2—February - Emerging Infectious Diseases journal - CDC
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 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 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. Worldwide, more than species have been described and many are specific to a particular host species of mammal .
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 s, 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.
In , we found B.