Lice Samples Research Articles

Molecular detection of Bartonella quintana, Acinetobacter baumannii and Acinetobacter haemolyticus in Pediculus humanus lice in Nigeria, West Africa.

The human lice Pediculus humanus is distributed worldwide but, it thrives and flourishes under conflict situations where people are forced to live in crowded unhygienic conditions. Molecular methods were used to identify and screen human lice for the DNA of pathogens of public health importance in an area that has been under insurgency related to religious and political conflicts with tens of thousands of internally displaced people (IDP). DNA of Bartonella quintana, Acinetobacter baumannii and Acinetobacter haemolyticus was detected in 18.3%, 40.0% and 1.7%, respectively, of human lice collected from children in Maiduguri, Nigeria. More body lice than head lice were positive for pathogen's DNA (64.3% vs. 44.4%; χ2 = 1.3, p = 0.33), but the difference was not significant. Two lice samples were found to harbour mixed DNA of B. quintana and A. baumannii. Phylogenetic analysis of the cytochrome b (cytb) gene sequences of the positive lice specimens placed them into clades A and E. This is the first report on the molecular identification of human lice and the detection of the DNA of pathogens of public health importance in lice in Nigeria, West Africa. The findings of this study will assist policy makers and medical practitioners in formulating a holistic healthcare delivery to IDPs.

A circumpolar parasite: Evidence of a cryptic undescribed species of sucking louse, Linognathus sp., collected from Arctic foxes, Vulpes lagopus, in Nunavut (Canada) and Svalbard (Norway).

The North has experienced unprecedented rates of warming over the past few decades, impacting the survival and development of insects and the pathogens that they carry. Since 2019, Arctic foxes from Canada (Nunavut) have been observed with fur loss inconsistent with natural shedding of fur. Adult lice were collected from Arctic foxes from Nunavut (n = 1) and Svalbard (n = 2; Norway) and were identified as sucking lice (suborder Anoplura). Using conventional PCR targeting the mitochondrial cytochrome c oxidase subunit 1 gene (cox1), lice from Canada and Svalbard were 100% similar (8 pooled samples from Nunavut and 3 pooled samples from Svalbard), indicating that there is potential gene flow between ectoparasites on Scandinavian and North American Arctic fox populations. The cox1 sequences of Arctic fox lice and dog sucking lice (Linognathus setosus) had significant differences (87% identity), suggesting that foxes may harbour a cryptic species that has not previously been recognised. Conventional PCR targeting the gltA gene for Bartonella bacteria amplified DNA from an unknown gammaproteobacteria from two pooled louse samples collected from Svalbard foxes. The amplified sequences were 100% identical to each other but were only 78% like Proteus mirabilis reported in GenBank (CP053614), suggesting that lice on Arctic foxes may carry unique microorganisms that have yet to be described.

Ứng dụng kỹ thuật giải trình tự gen phát hiện Rickettsia gây bệnh sốt nổi mụn (Rickettsia SFG) từ mẫu ngoại ký sinh thu thập tại Hà Giang

Rickettsiosis is a zoonotic disease caused by Rickettsiae which are gram negative bacteria, obligate intracellular. These pathogens are transmitted to human through infected ticks, mites, fleas, lice, louse… In this study, The 17kDa and OmpA partial genes of Rickettsia were amplified to detect Rickettsial DNA in buffalo ticks and louse (Haematopinus tuberculatus) collected in Ha Giang province. The PCR products were sequenced, analyzed and build phylogenetic tree by Bioedit, Mega-X softwares; were compared and identified the reference strain sequences by BLAST- NCBI, USA. The results indicated that 14/25 tick samples and 2/14 louse samples were positive for Rickettsia SFG by PCR. Sequence analysis of OmpA gen showed that 14 clone isolated from the tick samples exhibites a 98% - 100% similarity to Rickettsia japonica, whereas 2 clone isolated from the louse samples were 98% similar to Rickettsia massiliae. Thus, our research showed that Rickettsia SFG including Rickettsia japonica and Rickettsia massiliae were detected in ticks and louse, respectively collected in Ha Giang province, Vietnam.

Biochemical constituents and insecticidal activities of Callistemon viminalis essential oil against adults and eggs of Pediculus humanus capitis (Phthiraptera: Pediculidae)

BackgroundSynthetic chemical pediculicides used for head-louse treatment do not kill louse eggs, can induce side effects in humans, and lead to genetic resistance in lice worldwide, including in Thailand. Use of phytoconstituents, particularly plant-derived essential oils, is alternatively recommended for head lice. PurposeTo identify biochemical constituents of Callistemon viminalis essential oil (EO) and to assess the ex vivo effects of EO on head lice and their eggs. MethodsThe EO was extracted from fresh leaves C. viminalis by stream distillation, and the biochemical constituents were identified by gas chromatography-mass spectrometry (GC–MS). Louse samples were collected from schools in Khon Kaen Province, Thailand for ex vivo tests. Pediculicidal activity of EO was investigated using topical contact, and ovicidal activity was assessed using immersion and topical tests. Adult lice were observed for 8 h after treatment and eggs were observed for 3 weeks to assess pediculicidal and ovicidal effects, respectively. Mortality was noted and morphological change was recorded for head lice using scanning electron microscopy. Inhibition of egg hatching was evaluated. ResultsForty-four phytochemical components were identified in EO obtained from fresh leaves of C. viminalis. The most abundant were 1,8-cineole (66.96%), α-pinene (18.74%) and o-cymene (7.02%). Ex vivo, C. viminalis EO at concentrations above 10% for 30 min caused 100% adult mortality using a topical bioassay. In a complete-immersion test, all head louse eggs failed to hatch after exposure to concentrations of C. viminalis EO of 10% or greater for 10 min. Eggs were less sensitive using a topical method. Permethrin 1%, coconut oil and distilled water exhibited low efficacy against both crawling and egg stages. Scanning electron micrographs indicated that C. viminalis EO caused obstruction in some louse spiracles but had no effect on the cuticle or sensory hairs. ConclusionThe EO derived from C. viminalis had higher ex vivo efficacy against head lice and their eggs than 1% did permethrin. This EO may be a starting point for developing natural pediculicides to control head lice that are susceptible or resistant to permethrin.

Molecular detection of Rickettsia in ectoparasites (Siphonaptera and Phthiraptera) of domestic and feral pigs from Argentina.

Rickettsioses are distributed among a variety of hematophagous arthropods, and represent an emergent threat. The presence of rickettsial bacteria in ectoparasites collected from pigs from Argentina is still unknown. This study investigated the presence and identity of Rickettsia spp. in fleas, Pulex irritans, and sucking lice, Haematopinus suis, of domestic and feral pigs, Sus scrofa, from Central-Northern Argentina, through the genes gltA and ompB. Rickettsial bacteria were detected in 50% of fleas and 24% of lice. The BLASTn analysis of the ompB gene fragments in P. irritans samples showed identities 99% and 100% with R. felis. Positive samples of H. suis were 99% similar with species from the spotted fever group, future amplifications of a more polymorphic fragment of the ompB gene will allow to corroborate the identity of the Rickettsia species present in these lice samples. The Rickettsia spp. reported in the present study are having eventually been associated with cases of human diseases, and the circulation of these agents in arthropods has already been reported in several countries. Therefore, the identification of circulating pathogenic agents, such as reported in this study, is crucial for development of preventive measures for the control of ectoparasite-borne rickettsiosis diseases. Further studies, using serology techniques, will be allow to explore the ability of pigs as a possible Rickettsia reservoir and its role as part of transmission cycle of Rickettsia spp. in the studied scenarios.

New Records of Bartonella spp. and Rickettsia spp. in Lice Collected from Small Rodents.

Lice are blood-sucking insects that are of medical and veterinary significance as parasites and vectors for various infectious agents. More than half of described blood-sucking lice species are found on rodents. Rodents are important hosts of several Bartonella and Rickettsia species, and some of these bacteria are characterized as human pathogens in Europe. Rodent ectoparasites, such as fleas and ticks, are important vectors of Bartonella spp. and Rickettsia spp., but knowledge about the presence of these bacteria in lice is limited. The aim of this study was to determine the prevalence of Bartonella and Rickettsia bacteria in lice collected from rodents in Slovakia. The ectoparasites were collected from small rodents captured from 2010 to 2015 at four different sites in eastern Slovakia. The presence of Bartonella and Rickettsia species in lice samples was screened by real-time PCR, targeting ssrA and gltA genes, respectively. The molecular characterization of the Bartonella strains was based on sequence analysis of partial rpoB and intergenic spacer (ITS) genes, and of the Rickettsia species on sequence analysis of the gltA gene. A total of 1074 lice of seven species were collected from six rodent species. Bartonella DNA was detected in Hoplopleura affinis (collected from Apodemus agrarius, Apodemus flavicollis, and Myodes glareolus), Polyplax serrata (from A. agrarius), and Hoplopleura sp. (from A. flavicollis). Sequence analysis revealed that the Bartonella strains belonged to the Bartonella coopersplainsensis, Bartonella tribocorum, and Bartonella taylorii genogroups. Rickettsia DNA was detected in H. affinis and P. serrata collected from A. agrarius. Sequence analysis revealed two Rickettsia species: Rickettsia helvetica and Rickettsia sp. The results of the study confirm the presence of Bartonella spp. and Rickettsia spp. in lice collected from rodents.

Detection of Bartonella quintana Infection among the Homeless Population in Tokyo, Japan, from 2013-2015.

Several outbreaks of trench fever caused by Bartonella quintana occurred in soldiers during World Wars I and II. Although trench fever cases have been decreasing worldwide, the disease was reported among the homeless population in developing and developed countries. The current prevalence of B. quintana infection in Japan is unclear. Blood and body louse (Pediculus humanus humanus) samples were obtained from homeless inpatients with body lice during emergency hospitalization in Tokyo from January 2013 to March 2015. Patients were tested for B. quintana infections using the culture method, polymerase chain reaction, and indirect immunofluorescence assay (IFA). Among the 29 patients tested, the presence of Bartonella spp. was confirmed by genomic sequencing of DNA extracted from two samples from blood culture performed for 15 out of 29 patients and from body louse samples of 20 patients (69%). Immunoglobulin G against B. quintana was detected in 10 patients (34.5%) at a cut-off titer of 1:256 in IFA. B. quintana infection was detected in samples obtained between 2013 and 2015 in Tokyo and needs to be on the list of differential diagnoses performed for febrile homeless individuals.

Planktonic and Parasitic Sea Lice Abundance on Three Commercial Salmon Farms in Norway Throughout a Production Cycle

The present article reports the densities of planktonic sea lice (Lepeophtheirus salmonis and Caligus elongatus) in three Atlantic salmon (Salmo salar) localities, and the relationship between the abundance of adult sea lice on the salmon and the densities of planktonic sea lice stages, during a complete production cycle followed by a fallowing period. Samples were taken downstream inside and immediately outside of cages, at one locality with lice skirts and two localities without lice skirts. There were no differences in densities of planktonic sea lice in samples taken from the inside or the outside of cages for any of the localities. However, the proportion-non-zero of planktonic sea lice samples taken from inside the cage was higher during months with a temperature above 9°C (mean abundance: 0.40–2.5 individuals m–3) than months with temperature below 9°C (mean abundance: 0.02–0.21 individuals m–3, odds ratio of the proportion-non-zero: p < 0.01). Densities of planktonic sea lice correlated most strongly with temperature in the first year (τ = 0.44–0.57, p < 0.05). A significant correlation between the number of adult female lice on salmon and average density of plankton sea lice was found in the locality with lice skirts during the second year (τ = 0.43 inside cages, τ = 0.58 outside cages, both p values < 0.05). Background levels of planktonic sea lice in the succeeding fallowing period showed neither L. salmonis nor C. elongatus planktonic sea lice, suggesting that there was successful reduction of the densities of planktonic sea lice for this area during the fallowing period.

Topical ivermectin in the treatment of pediculosis capitis

Background: Head lice infestation is considered a prominent issue because of its worldwide distribution, especially among children. Millions of children are infested with pediculosis capitis every year. The increasing rate of lice infestation has been reported even in the developed countries due to the resistance to known pediculicides. Besides, the louse is a vector for serious diseases, such as epidemic typhus fever. Objective: The aim of this work was the search for a new cheap and effective drug for pediculosis capitis. 2% ivermectin solution, a promising novel drug used for endoparasite and ectoparasite infections, was used in this study. Materials and Methods: This was a clinical trial study. The in vitro study was carried out in a period of five months. Samples of nits and lice were collected from female patients of the Department of Dermatology and Venereology, Baghdad Teaching Hospital. The study was conducted during a period from October 2002 through November 2003. One hundred fifty children from four primary schools in Hayy Al-A’amel, Baghdad, participated in this part of the study. The preparation was applied to the children by the author. One hundred children were tested with ivermectin solution and fifty children with rectified spirit. The first part of the study involved a parasitological evaluation (in vitro study) of pediculicidal and ovicidal activity, in which 4% ivermectin solution was discontinued because of contact dermatitis. Therefore, 2% ivermectin solution was used instead. Pediculicidal and ovicidal activity was examined half an hour afterward. The second part of the study involved a clinical evaluation (in situ study) of 2% ivermectin solution for half an hour. Results: Topical 2% ivermectin solution in rectified spirit is a good pediculicidal (100%) and a good ovicidal (88%) drug with good therapeutic efficacy (82% after the first application, 90% after the second application) against pediculosis capitis. Conclusion: The study described a novel topical preparation for pediculosis capitis, which was proven effective and safe.

6. In Vitro Insecticidal Activities of Ethanol Extract of Neem Leaves Against Heterodoxus Spiniger Lice In Dogs

Heterodoxus spiniger is a chewing lice that have been reported to infest dogs and cats. This ectoparasite is haematophagous and as an intermediate host in transmission of cysticercoids and egg of nematode worms. This study aims to determine the in vitro insecticidal activity of ethanol extract of neem leaf (Azadirachta indica) against H. spiniger. A total of 250 H. spiniger were divided into five groups with five replications, namely: P0 as a negative control group given placebo, P1 as a positive control group given deltamethrin 0.5EC 0.05%, and groups P2, P3 and P4 were given ethanol extract of neem leaves with concentrations of 2.5%, 5% and 10%. In each test, 10 lice samples were put into a petridish with a cotton swab that had been sprayed with the solution of each treatment, then the lice were treated again with fine spray evenly. The results showed that the in vitro ethanol extract of neem leaves had a very significant effect (P<0.01) on the mortality of H. spiniger. The best results are shown at 5% concentration which is capable of killing 100% of lice in 30 minutes. It can be concluded that the ethanol extract of neem leaf has insecticidal activity against H. spiniger.

Inventory and identification of ectoparasites lice on sheep in the Magetan regency, East-Java

Sheep are farm animals that have long been cultivated and become abundant food resources for humans. Sheep are particularly susceptible to ectoparasite attacks. One of ectoparasites that could infect sheep is lice, it can reduce the production of meat and decrease quality of leather and fleece. Therefore this research aims to inventory, identify, and study the existence of lice in sheep. Lice samples were collected in four districts in Magetan i.e Karas, Parang, Panekan, and Plaosan. Preparations of lice were done by whole-mount with Hoyer’s solution. Results showed that species of lice infesting sheep in four districts in Magetan was Damalinia ovis. The prevalence value of D. ovis infested sheep was 100%, it means that all examined sheeps were infested by D. ovis. The largest prevalence value was found on the sheep body (77.86%). The number of individual D. ovis found was not affected by the altitude, air temperature, and humidity.

The Prevalence of Bartonella Bacteria in Cattle Lice Collected from Three Provinces of Thailand.

Cattle lice are obligatory blood-sucking parasites, which is the cause of animal health problems worldwide. Recently, several studies have revealed that pathogenic bacteria could be found in cattle lice, and it can act as a potential vector for transmitting louse-borne diseases. However, the cattle lice and their pathogenic bacteria in Thailand have never been evaluated. In the present study, we aim to determine the presence of bacterial pathogens in cattle lice collected from three localities of Thailand. Total genomic DNA was extracted from 109 cattle louse samples and the Polymerase Chain Reaction (PCR) of 18S rRNA was developed to identify the cattle louse. Moreover, PCR was used for screening Bartonella spp., Acinetobacter spp., and Rickettsia spp. in cattle louse samples. The positive PCR products were cloned and sequenced. The phylogenetic tree based on the partial 18S rRNA sequences demonstrated that cattle lice species in this study are classified into two groups according to reference sequences; Haematopinus quadripertusus and Haematopinus spp. closely related to H. tuberculatus. The pathogen detection revealed that Bartonella spp. DNA of gltA and rpoB were detected in 25 of 109 samples (22.93%) both egg and adult stages, whereas Acinetobacter spp. and Rickettsia spp. were not detected in all cattle lice DNA samples. The gltA and rpoB sequences showed that the Bartonella spp. DNA was found in both H. quadripertusus and Haematopinus spp. closely related to H. tuberculatus. This study is the first report of the Bartonella spp. detected in cattle lice from Thailand. The finding obtained from this study could be used to determine whether the cattle lice can serve as a potential vector to transmit these pathogenic bacteria among cattle and may affect animal to human health.

Prevalence of Ticks and Lice parasites on a certain number of buffaloes in the district of Samarra/Iraq

This study included the detection of infection with Endo-parasites (Theleria, Babesia and Anaplasma) in buffaloes in Samarra city. Ninety blood samples were taken from buffaloes and it deal with various random ages ranged between1 month to 1 year. The current results showed that there is a major species of the tick, Hyalomma, which includes three types of Hyalomma, which include Hyalomma scupense, Hyalomma turanicum, and Hyalomma anatolicum. They were Hyalomma anatolicum anatolicum, 73.3%. It was parasitic on different parts of the body of the buffaloes, namely the ear, the thorax, and the region around the exit. While samples of lice showed the presence of the genus: Haematopinus tubrculatus of the rank of Anoplura by 26.7%.

Detection of bacterial pathogens in clade E head lice collected from Niger\u2019s refugees in Algeria

BackgroundHead 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.ResultsIn this study, 37 head lice samples were collected from 31 Nigerien refugees, as well as 45 head lice from 27 schoolchildren. The collection was established in three localities of eastern Algiers, north Algeria. Quantitative real-time PCR screening of pathogens bacteria and the genetic characterisation of the head lice satut were performed. Through amplification and sequencing of the cytb gene, results showed that all head lice of Nigerien refugees 37/82 (45.12%) belonged to clade E with the presence of four new haplotypes, while, of the 45 head lice of schoolchildren, 34/82 lice (41.46%) belonged to clade A and 11/82 (13.41%) belonged to clade B. Our study is the first to report the existence of clade E haplogroup in Nigerien head lice. DNA of Coxiella burnetii was detected in 3/37 (8.10%) of the head lice collected from 3 of the 31 (9.67%) migrant population. We also revealed the presence of Acinetobacter DNA in 20/37 (54.05%) of head lice collected from 25/31 (80.64%) of the Nigerien refugees, and in 25/45 (55.55%) head lice collected from 15/27 (55.55%) schoolchildren. All positive Nigerien-head lice for Acinetobacter spp. were identified as A. baumannii, while positive schoolchildren-head lice were identified as A. johnsonii 15/25 (60%), A. variabilis 8/25 (32%) and A. baumannii 2/25 (8%).ConclusionsBased on these findings from head lice collected on migrant and non-migrant population, our results show, for the first time, that head lice from Niger belong to haplogroup E, and confirm that the clade E had a west African distribution. We also detected, for the first time, the presence of C. burnetii and A. baumannii in these Nigerien head lice. Nevertheless, further studies are needed to determine whether the head lice can transmit these pathogenic bacteria from one person to another.

A 200K SNP chip reveals a novel Pacific salmon louse genotype linked to differential efficacy of emamectin benzoate

Antiparasitic drugs such as emamectin benzoate (EMB) are relied upon to reduce the parasite load, particularly of the sea louse Lepeophtheirus salmonis, on farmed salmon. The decline in EMB treatment efficacy for this purpose is an important issue for salmon producers around the world, and particularly for those in the Atlantic Ocean where widespread EMB tolerance in sea lice is recognized as a significant problem. Salmon farms in the Northeast Pacific Ocean have not historically experienced the same issues with treatment efficacy, possibly due to the relatively large population of endemic salmonid hosts that serve to both redistribute surviving lice and dilute populations potentially under selection by introducing naïve lice to farms. Frequent migration of lice among farmed and wild hosts should limit the effect of farm-specific selection pressures on changes to the overall allele frequencies of sea lice in the Pacific Ocean. A previous study using microsatellites examined L. salmonis oncorhynchi from 10 Pacific locations from wild and farmed hosts and found no population structure. Recently however, a farm population of sea lice was detected where EMB bioassay exposure tolerance was abnormally elevated. In response, we have developed a Pacific louse draft genome that complements the previously-released Atlantic louse sequence. These genomes were combined with whole-genome re-sequencing data to design a highly sensitive 201,279 marker SNP array applicable for both subspecies (90,827 validated Pacific loci; 153,569 validated Atlantic loci). Notably, kmer spectrum analysis of the re-sequenced samples indicated that Pacific lice exhibit a large within-individual heterozygosity rate (average of 1 in every 72 bases) that is markedly higher than that of Atlantic individuals (1 in every 173 bases). The SNP chip was used to produce a high-density map for Atlantic sea louse linkage group 5 that was previously shown to be associated with EMB tolerance in Atlantic lice. Additionally, 478 Pacific louse samples from farmed and wild hosts obtained between 2005 and 2014 were also genotyped on the array. Clustering analysis allowed us to detect the apparent emergence of an otherwise rare genotype at a high frequency among the lice collected from two farms in 2013 that had reported elevated EMB tolerance. This genotype was not observed in louse samples collected from the same farm in 2010, nor in any lice sampled from other locations prior to 2013. However, this genotype was detected at low frequencies in louse samples from farms in two locations reporting elevated EMB tolerance in 2014. These results suggest that a rare genotype present in Pacific lice may be locally expanded in farms after EMB treatment. Supporting this hypothesis, 437 SNPs associated with this genotype were found to be in a region of linkage group 5 that overlaps the region associated with EMB resistance in Atlantic lice. Finally, five of the top diagnostic SNPs within this region were used to screen lice that had been subjected to an EMB survival assay, revealing a significant association between these SNPs and EMB treatment outcome. To our knowledge this work is the first report to identify a genetic link to altered EMB efficacy in L. salmonis in the Pacific Ocean.

Phe362Tyr in AChE: A Major Factor Responsible for Azamethiphos Resistance in Lepeophtheirus salmonis in Norway.

Organophosphates (OP) are one of the major treatments used against the salmon louse (Lepeophtherius salmonis) in Norwegian salmonid aquaculture. The use of OP since the late 1970s has resulted in widespread resistant parasites. Recently, we reported a single mutation (Phe362Tyr) in acetylcholinesterase (AChE) as the major mechanism behind resistance in salmon louse towards OP. The present study was carried out to validate this mechanism at the field level. A total of 6658 salmon louse samples were enrolled from 56 different fish farms across the Norwegian coast, from Vest Agder in the south to Finnmark in the north. All the samples were genotyped using a TaqMan probe assay for the Phe362Tyr mutation. A strong association was observed between areas with frequent use of the OP (azamethiphos) and the Phe362Tyr mutation. This was confirmed at 15 sites where results from independently conducted bioassays and genotyping of parasites correlated well. Furthermore, genotyping of surviving and moribund parasites from six bioassay experiments demonstrated a highly significant negative correlation between the frequency of resistance alleles and the probability of dying when exposed to azamethiphos in a bioassay. Based on these observations, we could strongly conclude that the Phe362Tyr mutation is a major factor responsible for OP resistance in salmon louse on Norwegian fish farms.

Molecular survey of the head louse Pediculus humanus capitis in Thailand and its potential role for transmitting Acinetobacter spp.

BackgroundHead louse infestation, which is caused by Pediculus humanus capitis, occurs throughout the world. With the advent of molecular techniques, head lice have been classified into three clades. Recent reports have demonstrated that pathogenic organisms could be found in head lice. Head lice and their pathogenic bacteria in Thailand have never been investigated. In this study, we determined the genetic diversity of head lice collected from various areas of Thailand and demonstrated the presence of Acinetobacter spp. in head lice.MethodsTotal DNA was extracted from 275 head louse samples that were collected from several geographic regions of Thailand. PCR was used to amplify the head louse COI gene and for detection of Bartonella spp. and Acinetobacter spp. The amplified PCR amplicons were cloned and sequenced. The DNA sequences were analyzed via the neighbor-joining method using Kimura’s 2-parameter model.ResultsThe phylogenetic tree based on the COI gene revealed that head lice in Thailand are clearly classified into two clades (A and C). Bartonella spp. was not detected in all the samples, whereas Acinetobacter spp. was detected in 10 samples (3.62%), which consisted of A. baumannii (1.45%), A. radioresistens (1.45%), and A. schindleri (0.72%). The relationship of Acinetobacter spp. and the head lice clades showed that Acinetobacter spp. was found in clade A and C.ConclusionsHead lice in Thailand are classified into clade A and B based on the COI gene sequences. Pathogenic Acinetobacter spp. was detected in both clades. The data obtained from the study might assist in the development of effective strategies for head lice control in the future. Detection of pathogenic bacteria in head lice could raise awareness of head lice as a source of nosocomial bacterial infections.

A New Louse Species: Aegypoecus guralpi sp. n. (Phthiraptera: Ischnocera) from a Long-legged Buzzard (Buteo rufinus)

A total of ten louse samples were collected from a long-legged buzzard (Buteo rufinus) in Hatay province in Mediterranean Region of Turkey. All of the louse samples were identified as a new species morphologically and named as Aegypoecus guralpi.

Chewing lice (Phthiraptera: Amblycera and Ischnocera) from wild birds in southern Vietnam, with descriptions of two new species.

A total of 239 individuals of 50 bird species were examined for chewing lice (Insecta: Phthiraptera) in southern Vietnam. Fifty-six birds of 20 species were parasitised by 15 species of lice belonging to 10 genera from two suborders, Amblycera: Menacanthus, Meromenopon, Myrsidea, and Ischnocera: Alcedoecus, Brueelia, Cuculicola, Meropoecus, Penenirmus, Philopteroides and Philopterus. Thirteen louse samples from Passeriformes were identified to genus only because they contain inadequate material. A total of 29 host-louse associations were found, of which nine are new, including: (1) two new species of the genus Brueelia, which are described and named in this paper: Brueelia binhchauensis from Megalaima lineata (Vieillot, 1816) (Piciformes: Megalaimidae), and Brueelia malacocincla from Malacocincla abbotti Blyth, 1845 (Passeriformes: Pellorneidae); (2) first records of lice from Cyornis hainanus (Ogilvie-Grant, 1900); and (3) the first record of Myrsidea claytoni Hellenthal & Price, 2003 from Cymbirhynchus macrorhynchos (Gmelin, 1788) (Passeriformes: Eurylaimidae), here regarded as a case of natural host-switching. A portion of the mitochondrial cytochrome oxidase I (COI) gene for some species of chewing lice was sequenced in order to assess their genetic divergences.

Assessment of population structure in Pacific Lepeophtheirus salmonis (Krøyer) using single nucleotide polymorphism and microsatellite genetic markers

The ectoparasitic sea louse, Lepeophtheirus salmonis (Krøyer), has caused great concern for both wild salmon fisheries and the salmon aquaculture industry. Identifying the population structure of this parasite is important for better understanding its dispersal capabilities and controlling louse infections. Most of the sea lice population studies carried out to date have been focused on Atlantic Ocean L. salmonis where host parasite interactions may be quite different than those in the Pacific Ocean. In this study we examined the genetic population structure of sea lice from 12 Pacific Ocean samples ranging from the Bering Sea to southern Vancouver Island using 27 microsatellite and 87 single nucleotide polymorphisms (SNPs) from 25 loci. Louse samples were analyzed for genetic differentiation among farmed and wild host salmon in addition to temporal differentiation from 2007 to 2009 and spatial differentiation over the entire sampling range. Our analyses failed to resolve significant population structure in L. salmonis for any of these three comparisons. Our results therefore support a hypothesis of high migration and panmixis of L. salmonis within the studied area of the Pacific Ocean.