Prevalence and associated risk factors of anti-Coxiella burnetii antibodies in dairy cattle herds using bulk tank milk analysis in Kabylia area, north Algeria.

Coxiella burnetii, or Q fever agent, has notable implications for human and livestock health. Infections in cattle primarily manifest through reproductive issues where infected animals shed the bacterium in birth fluids, placental tissues, and milk, serving as potential sources of transmission. Bovine herds become reservoirs, contributing to the environmental contamination of farming areas. Comprehensive studies on the prevalence, transmission routes, and associated risk factors among cattle contribute to the development of effective control strategies, ultimately safeguarding both livestock and public health.Here we determine the prevalence of Coxiella burnetii antibodies against in dairy cattle farms from Kabylia (northern Algeria) and identify the associated risk factors. Bulk tank milk samples from 184 farms were analyzed by indirect ELISA technique, 49 of them were tested positive which corresponds to a prevalence rate of 26.63% (95% CI 20.25-33.01%). Multivariate analysis by logistic regression showed that the risk factors associated with detection of anti-Coxiella burnetii antibodies are: cohabitation of cattle with small ruminants(OR = 3.74 95% CI [1.41-8.92]), exposure to prevailing winds (OR = 5.12 95% CI [2.11-13.45]), and the veterinarian visits frequency(OR = 5.67 95% CI [2.55-13.60]). These findings underscore the susceptibility of dairy cattle to Q fever in the Kabylia region, highlighting practices that pose risks. We recommend the implementation of hygienic measures and adherence to proper farming conditions to mitigate the transmission of Q fever and reduce the associated zoonotic risk.

Bartonella raoultii sp. nov., isolated from infected rodents (Mastomys erythroleucus) in Senegal.

Bartonella species are involved in various human diseases, causing a range of clinical manifestations; animals are considered as the main reservoirs, transmitting diverse species of Bartonella through direct contact and haematophagous insects. Here, we characterize a new species, Bartonella raoultii sp. nov., within the genus Bartonella, using a taxonogenomic polyphasic approach. Strain 094T (= CSUR B1097T=DSM 28004T), isolated from the blood of an infected rodent (Mastomys erythroleucus) in Senegal, is an aerobic and rod-shaped bacterium. The annotated non-contiguous genome sequence is 1 952322 bp long and contains 37.2 mol% G+C content, 1686 protein-coding genes and 50 RNA genes, including seven rRNA genes.

The anti-immune dengue subgenomic flaviviral RNA is present in vesicles in mosquito saliva and is associated with increased infectivity.

Mosquito transmission of dengue viruses to humans starts with infection of skin resident cells at the biting site. There is great interest in identifying transmission-enhancing factors in mosquito saliva in order to counteract them. Here we report the discovery of high levels of the anti-immune subgenomic flaviviral RNA (sfRNA) in dengue virus 2-infected mosquito saliva. We established that sfRNA is present in saliva using three different methods: northern blot, RT-qPCR and RNA sequencing. We next show that salivary sfRNA is protected in detergent-sensitive compartments, likely extracellular vesicles. In support of this hypothesis, we visualized viral RNAs in vesicles in mosquito saliva and noted a marked enrichment of signal from 3'UTR sequences, which is consistent with the presence of sfRNA. Furthermore, we show that incubation with mosquito saliva containing higher sfRNA levels results in higher virus infectivity in a human hepatoma cell line and human primary dermal fibroblasts. Transfection of 3'UTR RNA prior to DENV2 infection inhibited type I and III interferon induction and signaling, and enhanced viral replication. Therefore, we posit that sfRNA present in salivary extracellular vesicles is delivered to cells at the biting site to inhibit innate immunity and enhance dengue virus transmission.

Detection of Potential Zoonotic Bartonella Species in African Giant Rats (Cricetomys gambianus) and Fleas from an Urban Area in Senegal.

Bartonellae are bacteria associated with mammals and their ectoparasites. Rodents often host different species of Bartonella. The aim of this study was to investigate the presence of Bartonella spp. in African giant pouched rats (Cricetomys gambianus) and their ectoparasites in Dakar, Senegal. In 2012, 20 rats were caught, and their fleas were identified. DNA was extracted from 170 selected fleas and qPCR was carried out to detect Bartonella spp. Subsequently, a Bartonella culture was performed from the rat blood samples and the isolated strains (16S rRNA, rpoB, ftsZ and ITS3) were genotyped. A total of 1117 fleas were collected from 19 rats and identified as Xenopsylla cheopis, the tropical rat flea. Bartonella DNA was detected in 148 of 170 selected fleas (87.1%). In addition, Bartonella strains were isolated from the blood of 17 rats (85%). According to Bartonella gene-sequence-based criteria for species definition, the isolated strains were identified as B. massiliensis (four strains) and two potential new species related to the zoonotic B. elizabethae. In this paper, these potentially new species are provisionally called Candidatus Bartonella militaris (11 strains) and Candidatus Bartonella affinis (two strains) until their description has been completed. Cricetomys gambianus and its fleas could constitute a public health risk in Dakar due to the high prevalence of Bartonella infection reported.

Use of the proteomic tool MALDI-TOF MS in termite identification.

Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS) has proved effective for the identification of many arthropods. A total of 432 termite specimens were collected in Mali, Cote d'Ivoire, Togo, Senegal, Switzerland and France. Morphologically, 22 species were identified, including Ancistrotermes cavithorax, Amitermes evuncifer, Cryptotermes brevis, Cubitermes orthognathus, Kalotermes flavicollis, Macrotermes bellicosus, Macrotermes herus, Macrotermes ivorensis, Macrotermes subhyalinus, Microcerotermes parvus, Microtermes sp., Odontotermes latericius, Procubitermes sjostedti, Promirotermes holmgreni, Reticulitermes grassei, Reticulitermes lucifugus, Reticulitermes santonensis, Trinervitermes geminatus, Trinervitermes occidentalis, Trinervitermes togoensis, Trinervitermes sp., Trinervitermes trinervoides and Trinervitermes trinervius. Analysis of MALDI-TOF MS spectra profiles from termites revealed that all were of high quality, with intra-species reproducibility and inter-species specificity. Blind testing of the spectra of 389 termites against our updated database with the spectra of 43 specimens of different termite species revealed that all were correctly identified with log score values (LSVs) ranging from 1.65 to 2.851, mean 2.290 ± 0.225, median 2.299, and 98.4% (383) had LSVs > 1.8. This study is the first on the use of MALDI-TOF for termite identification and shows its importance as a tool for arthropod taxonomy and reinforces the idea that MALDI-TOF MS is a promising tool in the field of entomology.

First evidence of human-to-dog transmission of SARS-CoV-2 B.1.160 variant in France.

Since the start of the coronavirus disease of 2019 (COVID-19) pandemic, several episodes of human-to-animal severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission have been described in different countries. The role of pets, especially domestic dogs, in the COVID-19 epidemiology is highly questionable and needs further investigation. In this study, we report a case of COVID-19 in a French dog living in close contact with its owners who were COVID-19 patients. The dog presented rhinitis and was sampled 1 week after its owners (a man and a woman) were tested positive for COVID-19. The nasal swabs for the dog tested remained positive for SARS-CoV-2 by reverse transcription quantitative real-time PCR (RT-qPCR) 1 month following the first diagnosis. Specific anti-SARS-CoV-2 antibodies were detectable 12 days after the first diagnosis and persisted for at least 5 months as tested using enzyme-linked immunoassay (ELISA) and automated western blotting. The whole-genome sequences from the dog and its owners were 99%-100% identical (with the man and the woman's sequences, respectively) and matched the B.1.160 variant of concern (Marseille-4 variant), the most widespread in France at the time the dog was infected. This study documents the first detection of B.1.160 in pets (a dog) in France, and the first canine genome recovery of the B.1.160 variant of global concern. Moreover, given the enhanced infectivity and transmissibility of the Marseille-4 variant for humans, this case also highlights the risk that pets may potentially play a significant role in SARS-CoV-2 outbreaks and may transmit the infection to humans. We have evidence of human-to-dog transmission of the Marseille-4 variant since the owners were first to be infected. Finally, owners and veterinarians must be vigilent for canine COVID-19 when dogs are presented with respiratory clinical signs.

SARS-CoV-2 antibodies seroprevalence in dogs from France using ELISA and an automated western blotting assay.

Dogs are occasionally susceptible to SARS-CoV-2, developing few or no clinical signs. Epidemiological surveillance of SARS-CoV-2 in dogs requires testing to distinguish it from other canine coronaviruses. In the last year, significant advances have been made in the diagnosis of SARS-CoV-2, allowing its surveillance in both human and animal populations. Here, using ELISA and automated western blotting (AWB) assays, we performed a longitudinal study on 809 apparently healthy dogs from different regions of France to investigate anti-SARS-CoV-2 antibodies. There were three main groups: (i) 356 dogs sampled once before the pandemic, (ii) 235 dogs sampled once during the pandemic, and (iii) 218 dogs, including 82 dogs sampled twice (before and during the pandemic), 125 dogs sampled twice during the pandemic and 11 dogs sampled three times (once before and twice during the pandemic). Using ELISA, seroprevalence was significantly higher during the pandemic [5.5% (25/453)] than during the pre-pandemic period [1.1% (5/449)]. Among the 218 dogs sampled twice, at least 8 ELISA-seroconversions were observed. ELISA positive pre-pandemic sera were not confirmed in serial tests by AWB, indicating possible ELISA cross-reactivity, probably with other canine coronaviruses. A significant difference was observed between these two serological tests (Q = 88, p = 0.008). A clear correlation was observed between SARS-CoV-2 seroprevalence in dogs and the incidence of SARS-CoV-2 infection in human population from the same area. AWB could be used as a second line assay to confirm the doubtful and discrepant ELISA results in dogs. Our results confirm the previous experimental models regarding the susceptibility of dogs to SARS-CoV-2, suggesting that viral transmission from and between dogs is weak or absent. However, the new variants with multiple mutations could adapt to dogs; this hypothesis cannot be ruled out in the absence of genomic data on SARS-CoV-2 from dogs.

Bacterial Infections in Humans and Nonhuman Primates from Africa: Expanding the Knowledge.

The close phylogenetic relationship between humans and other primates creates exceptionally high potential for pathogen exchange. The surveillance of pathogens in primates plays an important role in anticipating possible outbreaks. In this study, we conducted a molecular investigation of pathogenic bacteria in feces from African nonhuman primates (NHPs). We also investigated the pathogens shared by the human population and gorillas living in the same territory in the Republic of Congo. In total, 93% of NHPs (n=176) and 95% (n=38) of humans were found to carry at least one bacterium. Non-pallidum Treponema spp. (including T. succinifaciens, T. berlinense, and several potential new species) were recovered from stools of 70% of great apes, 88% of monkeys, and 79% of humans. Non-tuberculosis Mycobacterium spp. were also common in almost all NHP species as well as in humans. In addition, Acinetobacter spp., members of the primate gut microbiota, were mainly prevalent in human and gorilla. Pathogenic Leptospira spp. were highly present in humans (82%) and gorillas (66%) stool samples in Congo, but were absent in the other NHPs, therefore suggesting a possible gorillas-humans exchange. Particular attention will be necessary for enteropathogenic bacteria detected in humans such as Helicobacter pylori, Salmonella spp. (including S. typhi/paratyphi), Staphyloccocus aureus, and Tropheryma whipplei, some of which were also present in gorillas in the same territory (S. aureus and T. whipplei). This study enhances our knowledge of pathogenic bacteria that threaten African NHPs and humans by using a non-invasive sampling technique. Contact between humans and NHPs results in an exchange of pathogens. Ongoing surveillance, prevention, and treatment strategies alone will limit the spread of these infectious agents.

Multidrug-Resistant Klebsiella pneumoniae Clones from Wild Chimpanzees and Termites in Senegal.

Antibiotic resistance genes exist naturally in various environments far from human usage. Here, we investigated multidrug-resistant Klebsiella pneumoniae, a common pathogen of chimpanzees and humans. We screened antibiotic-resistant K. pneumoniae from 48 chimpanzee stools and 38 termite mounds (n = 415 samples) collected in protected areas in Senegal. The microsatellite method was used to identify chimpanzee individuals (n = 13). Whole-genome sequencing was performed on K. pneumoniae complex isolates to identify antibiotic-resistant genes and characterize clones. We found a high prevalence of carbapenem-resistant K. pneumoniae among chimpanzee isolates (18/48 samples from 7/13 individuals) and ceftriaxone resistance among both chimpanzee individuals (19/48) and termite mounds (7/415 termites and 3/38 termite mounds). The blaOXA-48 and the blaKPC-2 genes were carried by international pOXA-48 and pKPC-2 plasmids, respectively. The ESBL plasmid carried blaCTX-M-15, blaTEM-1B, and blaOXA-1 genes. Genome sequencing of 56 isolates identified two major clones associated with hospital-acquired infections of K. pneumoniae (ST307 and ST147) in chimpanzees and termites, suggesting circulation of strains between the two species, as chimpanzees feed on termites. The source and selection pressure of these clones in this environment need to be explored.

Severe pneumonia in a street rat (Rattus norvegicus) caused by Rodentibacter rarus strain RMC2.

Background: Rodents are one of the most dangerous reservoirs and carriers of infectious diseases. Gradually, rats have become predominant in cities, sometimes staying in close vicinity to humans, pets, and other animals. Consequently, they tend to increase the transmission risk of pathogens. Case Description: Here, we report an original case of bacterial pneumonia in a street rat (Rattus norvegicus). The rat was found dead on a street in the chief town of Marseille (France) after being run over by a car. The necropsy of the corpse revealed generalized granulomatous pneumonia in almost all the pulmonary lobes. Lung lesions and predominantly multiple fibro-inflammatory areas are presumably the witness of an infectious etiology. Bacterial isolation was carried out from lung tissues. Colonies were identified by MALDI-TOF MS and confirmed by 16S rRNA sequencing. The following bacteria were identified: Staphylococcus cohnii, Bordetella bronchiseptica, Bordetella parapertussi, Corynebacterium glucuronolyticum, Pelistega suis and Rodentibacter rarus. Based on the histopathological diagnosis and the avoidance approach, the most likely etiological agent of pneumonia is therefore R. rarus, a little-known Pasteurellales bacterium that is closely related to Rodentibacter pneumotropicus. Conclusion: These data emphasize the severity of R. rarus infection in rodents. Thus, pointing out a potential risk for other animals (dogs, cats, and birds), as well as humans. The health monitoring program for rodents and rabbits pasteurellosis should now include R. rarus. Therefore, the pathological effect of the Rodentibacterspecies and/or strains needs to be better explored.

Stool Serology: Development of a Non-Invasive Immunological Method for the Detection of Enterovirus-Specific Antibodies in Congo Gorilla Faeces.

BACKGROUND: The incidence of poliovirus has been significantly reduced by as much as 99.9% globally. Alongside this, however, vaccine-associated paralytic poliomyelitis has emerged. Previously, our team reported in the Lésio-Louna-Léfini Nature Reserve (Republic of Congo) the presence of a new Enterovirus C (Ibou002) in a male gorilla that was put away because of clinical symptoms of facial paralysis. This new virus, isolated was from the stool samples of this gorilla but also from the excrement of an eco-guardian, is very similar to Coxsackievirus (EV-C99) as well as poliovirus 1 and 2. We hypothesised that these symptoms might be due to poliovirus infection. To test our hypothesis, we developed and optimised a non-invasive immunoassay for the detection of Enterovirus-specific antibodies in gorilla faeces that could be useful for routine serosurveillance in such cases. METHODS: In order to assess the potential role of poliovirus infection, we have developed and optimised a protocol, based on the lyophilisation and solubilisation of small volumes of stool extracts from 16 gorilla and 3 humans, to detect specific antibodies by western blot and ELISA. RESULTS: First, total immunoglobulins were detected in the concentrated stool extracts. Specific antibodies were then detected in 4/16 gorilla samples and 2/3 human samples by western blot using both the polio vaccine antigen and the Ibou002 antigen and by ELISA using the polio vaccine antigen. Humoral responses were greater with the Ibou002 antigen. CONCLUSION: We therefore suggest that this recombinant virus could lead to a polio-like disease in the endangered western lowland gorilla. The development of a non-invasive approach to detect microorganism-specific immunoglobulins from faecal samples opens numerous prospects for application in zoonotic infectious diseases and could revolutionise the screening of animals for important emerging infections, such as Ebola fever, rabies and coronavirus infections.

Potential zoonotic pathogens hosted by endangered bonobos.

Few publications, often limited to one specific pathogen, have studied bonobos (Pan paniscus), our closest living relatives, as possible reservoirs of certain human infectious agents. Here, 91 stool samples from semicaptive bonobos and bonobos reintroduced in the wild, in the Democratic Republic of the Congo, were screened for different infectious agents: viruses, bacteria and parasites. We showed the presence of potentially zoonotic viral, bacterial or parasitic agents in stool samples, sometimes coinfecting the same individuals. A high prevalence of Human mastadenoviruses (HAdV-C, HAdV-B, HAdV-E) was observed. Encephalomyocarditis viruses were identified in semicaptive bonobos, although identified genotypes were different from those identified in the previous fatal myocarditis epidemic at the same site in 2009. Non-pallidum Treponema spp. including symbiotic T. succinifaciens, T. berlinense and several potential new species with unknown pathogenicity were identified. We detected DNA of non-tuberculosis Mycobacterium spp., Acinetobacter spp., Salmonella spp. as well as pathogenic Leptospira interrogans. Zoonotic parasites such as Taenia solium and Strongyloides stercoralis were predominantly present in wild bonobos, while Giardia lamblia was found only in bonobos in contact with humans, suggesting a possible exchange. One third of bonobos carried Oesophagostomum spp., particularly zoonotic O. stephanostomum and O. bifurcum-like species, as well as other uncharacterized Nematoda. Trypanosoma theileri has been identified in semicaptive bonobos. Pathogens typically known to be transmitted sexually were not identified. We present here the results of a reasonably-sized screening study detecting DNA/RNA sequence evidence of potentially pathogenic viruses and microorganisms in bonobo based on a noninvasive sampling method (feces) and focused PCR diagnostics.

Variations in respiratory pathogen carriage among a homeless population in a shelter for men in Marseille, France, March-July 2020: cross-sectional 1-day surveys.

We aimed to compare respiratory pathogen carriage by PCR during three different time periods in 2020 in sheltered homeless people in Marseille, France. The overall prevalence of respiratory pathogen carriage in late March-early April (69.9%) was significantly higher than in late April (42.3%) and mid-July (45.1%). Bacterial carriage significantly decreased between late March-early April and late April. SARS-CoV-2 was detected only in late March-early April samples (20.6%). Measures aiming at mitigating SARS-CoV-2 transmission were effective and also impacted bacterial carriage. Seasonal variations of bacterial carriage between winter and summer in this population were not marked.

Screening of SARS-CoV-2 among homeless people, asylum-seekers and other people living in precarious conditions in Marseille, France, March-April 2020.

BACKGROUND: Surveillance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among sheltered homeless and other vulnerable people might provide the information needed to prevent its spread within accommodation centres. METHODS: Data were obtained from 698 participants in different accommodation centres (411 homeless individuals, 77 asylum-seekers, 58 other people living in precarious conditions and 152 employees working in these accommodation centres) who completed questionnaires and had nasal samples collected between 26 March and 17 April 2020. SARS-CoV-2 carriage was assessed by quantitative PCR. RESULTS: We found a high acceptance rate (78.9%) for testing. Overall, 49 people (7.0%) were positive for SARS-CoV-2, including 37 homeless individuals (of 411, 9.0%) and 12 employees (of 152, 7.9%). SARS-CoV-2 positivity correlated with symptoms, although 51% of patients who tested positive did not report respiratory symptoms or fever. Among homeless people, being young (18-34 years) (odds ratio 3.83, 95% confidence interval 1.47-10.0, p = 0.006) and being housed in one specific shelter (odds ratio 9.13, 95% confidence interval 4.09-20.37, p < 0.001) were independent factors associated with SARS-CoV-2 positivity (rates of 11.4% and 20.6%, respectively). DISCUSSION: Symptom screening alone is insufficient to prevent SARS-CoV-2 transmission in vulnerable sheltered people. Systematic testing should be promoted.

Enzootic Hepatic Capillariasis (Calodium hepaticum) in Street Rats (Rattus norvegicus) from Marseille City, France.

Hepatic capillariasis is a rare and neglected zoonosis affecting wild and synanthropic small rodents. It is caused by infection with Calodium hepaticum in liver. Despite the worldwide distribution of the host Rattus norvegicus (brown or street rats) in the urban area, the epidemiological status of this parasitosis remains unknown. In the present study, we examined a total of 27 brown rats from the city centre and a garden (four km from the city centre) of Marseille, France. All rats were autopsied and 52% showed the presence of C. hepaticum eggs in the liver. This result draws general attention to public health risks, since street rats are living near the human population.

Potential of Artesunate in the treatment of visceral leishmaniasis in dogs naturally infected by Leishmania infantum: Efficacy evidence from a randomized field trial.

Leishmaniasis is among the world's most neglected diseases. Dogs are the main reservoirs/hosts of Leishmania infantum, causative agent of both canine and human visceral leishmaniosis. Canine leishmaniasis (CanL) represents a public health problem as one of the most prevalent zoonotic diseases worldwide. Current therapeutics present drawbacks; thus, there is a need for more effective, safer, and cheaper drugs. The aim of this study was to evaluate and to compare the efficacy of oral administration of artesunate or meglumine antimoniate/allopurinol in dogs with clinical leishmaniasis. Forty-two dogs with naturally occurring clinical leishmaniasis were included in this open-label, simple randomized positive-control clinical field trial with 6 months of follow-up. Dogs received meglumine antimoniate 100 mg/kg/day and allopurinol 30 mg/kg/day for 28 days (control group, n = 26) or artesunate 25 mg/kg/day for 6 days (test group, n = 16). The animals were evaluated for their clinical evolution, parasite load (by qPCR) and humoral response at different time points: 0, 30, 90, and 180 days after treatment. Data analyses showed a significant improvement in both groups in clinical scores, parasitemia and antibody titers after treatment. Compared to the control group, the artesunate group showed significantly lower clinical score (P = 0.0001), lower parasitemia (P = 0.0001) and antibody titers after 6 months of follow-up. Compared to baseline values, a rapid, significant reduction (P < 0.012) in antibody levels, 2.28- versus 3.04-fold for the control versus artesunate groups, respectively, was observed 30 days after treatment. Antibody levels continued to decrease further in the artesunate group, where 58% of cases became seronegative at the 6-month follow-up. All qPCR-positive dogs were negative after treatment with artesunate, while 14.3% remained positive with the appearance of two new cases in the control group. Artesunate was well tolerated, and no side effects were recorded. Treatment failures were similar in both groups with 27.27% (6/22), including 18.18% (4/22) mortality in the control group, versus 26.66% (4/15), including 13.33% (2/15) mortality in the artesunate group. This is the first report showing the potential of artesunate in the treatment of dogs with clinical leishmaniasis. Artesunate showed higher efficacy than the current first-line treatment for CanL without any adverse effects. It could be a good alternative chemotherapy for CanL, and may be considered for further studies in human leishmaniases. Further clinical trials are needed to confirm these findings, to determine if there are relapses after treatment and if dogs remain infective to sandflies, to define the ideal therapeutic dosage and duration of treatment with artesunate.

Enteroviruses from Humans and Great Apes in the Republic of Congo: Recombination within Enterovirus C Serotypes.

Enteroviruses (EVs) are viruses of the family Picornaviridae that cause mild to severe infections in humans and in several animal species, including non-human primates (NHPs). We conducted a survey and characterization of enteroviruses circulating between humans and great apes in the Congo. Fecal samples (N = 24) of gorillas and chimpanzees living close to or distant from humans in three Congolese parks were collected, as well as from healthy humans (N = 38) living around and within these parks. Enteroviruses were detected in 29.4% of gorilla and 13.15% of human feces, including wild and human-habituated gorillas, local humans and eco-guards. Two identical strains were isolated from two humans coming from two remote regions. Their genomes were similar and all genes showed their close similarity to coxsackieviruses, except for the 3C, 3D and 5'-UTR regions, where they were most similar to poliovirus 1 and 2, suggesting recombination. Recombination events were found between these strains, poliovirus 1 and 2 and EV-C99. It is possible that the same EV-C species circulated in both humans and apes in different regions in the Congo, which must be confirmed in other investigations. In addition, other studies are needed to further investigate the circulation and genetic diversity of enteroviruses in the great ape population, to draw a definitive conclusion on the different species and types of enteroviruses circulating in the Republic of Congo.

An Earliest Endosymbiont, Wolbachia massiliensis sp. nov., Strain PL13 from the Bed Bug (Cimex hemipterus), Type Strain of a New Supergroup T.

The symbiotic Wolbachia are the most sophisticated mutualistic bacterium among all insect-associated microbiota. Wolbachia-insect relationship fluctuates from the simple facultative/parasitic to an obligate nutritional-mutualistic association as it was the case of the bedbug-Wolbachia from Cimexlectularius. Understanding this association may help in the control of associated arthropods. Genomic data have proven to be reliable tools in resolving some aspects of these symbiotic associations. Although, Wolbachia appear to be fastidious or uncultivated bacteria which strongly limited their study. Here we proposed Drosophila S2 cell line for the isolation and culture model to study Wolbachia strains. We therefore isolated and characterized a novel Wolbachia strain associated with the bedbug Cimexhemipterus, designated as wChem strain PL13, and proposed Wolbachiamassiliensis sp. nov. strain wChem-PL13 a type strain of this new species from new supergroup T. Phylogenetically, T-supergroup was close to F and S-supergroups from insects and D-supergroup from filarial nematodes. We determined the 1,291,339-bp genome of wChem-PL13, which was the smallest insect-associated Wolbachia genomes. Overall, the wChem genome shared 50% of protein coding genes with the other insect-associated facultative Wolbachia strains. These findings highlight the diversity of Wolbachia genotypes as well as the Wolbachia-host relationship among Cimicinae subfamily. The wChem provides folate and riboflavin vitamins on which the host depends, while the bacteria had a limited translation mechanism suggesting its strong dependence to its hosts. However, the clear-cut distinction between mutualism and parasitism of the wChem in C. hemipterus cannot be yet ruled out.

Tabanids as possible pathogen vectors in Senegal (West Africa).

BACKGROUND: Species of the Tabanidae are potent vectors of human and animal diseases, but they have not been thoroughly investigated to date. In Senegal (West Africa), little information is available on these dipterans. Our objective in this study was to investigate Senegalese tabanids and their diversity by using molecular and proteomics approaches, as well as their associated pathogens. METHODS: A total of 171 female tabanids were collected, including 143 from Casamance and 28 from Niokolo-Koba. The samples were identified morphologically by PCR sequencing and by MALDI-TOF MS, and PCR analysis was employed for pathogen detection and blood-meal characterization. RESULTS: The morphological identification revealed four species concordantly with the molecular identification: Atylotus fuscipes (79.5%), Tabanus guineensis (16.4%), Chrysops distinctipennis (3.5%) and Tabanus taeniola (0.6%) (not identified by PCR). The molecular investigation of pathogens revealed the presence of Trypanosoma theileri (6.6%), Leishmania donovani (6.6%), Setaria digitata (1.5%), Rickettsia spp. (5.1%) and Anaplasmataceae bacteria (0.7%) in A. fuscipes. Tabanus guineensis was positive for L. donovani (35.7%), S. digitata (3.6%) and Anaplasmataceae (17.8%). Leishmania donovani has been detected in 50% of C. distinctipennis specimens and the only T. taeniola specimen. No Piroplasmida, Mansonella spp. or Coxeilla burnetii DNA was detected. In addition to humans (96.43%), Chlorocebus sabeus, a non-human primate, has been identified as a host of (3.57%) analysed tabanids. MALDI-TOF MS enabled us to correctly identify all tabanid species that had good quality spectra and to create a database for future identification. CONCLUSIONS: Tabanids in Senegal could be vectors of several pathogens threatening animal and public health. To fully characterize these dipterans, it is therefore necessary that researchers in entomology and infectiology employ molecular characterization and mass spectrometric techniques such as MALDI-TOF MS to analyse these dipterans in Senegal and West Africa.