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1.
BMC Genomics ; 20(1): 675, 2019 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-31455241

RESUMEN

BACKGROUND: The hard tick Hyalomma dromedarii is one of the most injurious ectoparasites affecting camels and apparently best adapted to deserts. As long-term blood feeders, ticks are threatened by host defense system compounds that can cause them to be rejected and, ultimately, to die. However, their saliva contains a cocktail of bioactive molecules that enables them to succeed in taking their blood meal. A recent sialotranscriptomic study uncovered the complexity of the salivary composition of the tick H. dromedarii and provided a database for a proteomic analysis. We carried out a proteomic-informed by transcriptomic (PIT) to identify proteins in salivary glands of both genders of this tick species. RESULTS: We reported the array of 1111 proteins identified in the salivary glands of H. dromedarii ticks. Only 24% of the proteins were shared by both genders, and concur with the previously described sialotranscriptome complexity. The comparative analysis of the salivary glands of both genders did not reveal any great differences in the number or class of proteins expressed their enzymatic composition or functional classification. Indeed, few proteins in the entire proteome matched those predicted from the transcriptome while others corresponded to other proteins of other tick species. CONCLUSION: This investigation represents the first proteomic study of H. dromedarii salivary glands. Our results shed light on the differences between the composition of H. dromedarii male and female salivary glands, thus enabling us to better understand the gender-specific strategy to feed successfully.


Asunto(s)
Proteínas de Artrópodos/genética , Proteoma/metabolismo , Garrapatas/genética , Animales , Proteínas de Artrópodos/metabolismo , Camelus , Femenino , Perfilación de la Expresión Génica , Masculino , Proteómica , Saliva/metabolismo , Glándulas Salivales/metabolismo , Garrapatas/metabolismo , Transcriptoma
2.
Int J Health Geogr ; 17(1): 4, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29444675

RESUMEN

BACKGROUND: Aedes-borne diseases as dengue, zika, chikungunya and yellow fever are an emerging problem worldwide, being transmitted by Aedes aegypti and Aedes albopictus. Lack of up to date information about the distribution of Aedes species hampers surveillance and control. Global databases have been compiled but these did not capture data in the WHO Eastern Mediterranean Region (EMR), and any models built using these datasets fail to identify highly suitable areas where one or both species may occur. The first objective of this study was therefore to update the existing Ae. aegypti (Linnaeus, 1762) and Ae. albopictus (Skuse, 1895) compendia and the second objective was to generate species distribution models targeted to the EMR. A final objective was to engage the WHO points of contacts within the region to provide feedback and hence validate all model outputs. METHODS: The Ae. aegypti and Ae. albopictus compendia provided by Kraemer et al. (Sci Data 2:150035, 2015; Dryad Digit Repos, 2015) were used as starting points. These datasets were extended with more recent species and disease data. In the next step, these sets were filtered using the Köppen-Geiger classification and the Mahalanobis distance. The occurrence data were supplemented with pseudo-absence data as input to Random Forests. The resulting suitability and maximum risk of establishment maps were combined into hard-classified maps per country for expert validation. RESULTS: The EMR datasets consisted of 1995 presence locations for Ae. aegypti and 2868 presence locations for Ae. albopictus. The resulting suitability maps indicated that there exist areas with high suitability and/or maximum risk of establishment for these disease vectors in contrast with previous model output. Precipitation and host availability, expressed as population density and night-time lights, were the most important variables for Ae. aegypti. Host availability was the most important predictor in case of Ae. albopictus. Internal validation was assessed geographically. External validation showed high agreement between the predicted maps and the experts' extensive knowledge of the terrain. CONCLUSION: Maps of distribution and maximum risk of establishment were created for Ae. aegypti and Ae. albopictus for the WHO EMR. These region-specific maps highlighted data gaps and these gaps will be filled using targeted monitoring and surveillance. This will increase the awareness and preparedness of the different countries for Aedes borne diseases.


Asunto(s)
Aedes , Mapeo Geográfico , Mosquitos Vectores , Organización Mundial de la Salud , Animales , Culicidae , Dengue/diagnóstico , Dengue/epidemiología , Predicción , Humanos , Región Mediterránea/epidemiología , Especificidad de la Especie , Fiebre Amarilla/diagnóstico , Fiebre Amarilla/epidemiología
3.
Mol Ecol ; 24(2): 508-21, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25482270

RESUMEN

In arthropods, the intracellular bacteria Wolbachia often induce cytoplasmic incompatibility (CI) between sperm and egg, which causes conditional embryonic death and promotes the spatial spread of Wolbachia infections into host populations. The ability of Wolbachia to spread in natural populations through CI has attracted attention for using these bacteria in vector-borne disease control. The dynamics of incompatible Wolbachia infections have been deeply investigated theoretically, whereas in natural populations, there are only few examples described, especially among incompatible infected hosts. Here, we have surveyed the distribution of two molecular Wolbachia strains (wPip11 and wPip31) infecting the mosquito Culex pipiens in Tunisia. We delineated a clear spatial structure of both infections, with a sharp contact zone separating their distribution areas. Crossing experiments with isofemale lines from different localities showed three crossing types: wPip11-infected males always sterilize wPip31-infected females; however, while most wPip31-infected males were compatible with wPip11-infected females, a few completely sterilize them. The wPip11 strain was thus expected to spread, but temporal dynamics over 7 years of monitoring shows the stability of the contact zone. We examined which factors may contribute to the observed stability, both theoretically and empirically. Population cage experiments, field samples and modelling did not support significant impacts of local adaptation or assortative mating on the stability of wPip infection structure. By contrast, low dispersal probability and metapopulation dynamics in the host Cx. pipiens probably play major roles. This study highlights the need of understanding CI dynamics in natural populations to design effective and sustainable Wolbachia-based control strategies.


Asunto(s)
Culex/microbiología , Genética de Población , Wolbachia/genética , Animales , Técnicas de Tipificación Bacteriana , Cruzamientos Genéticos , Femenino , Masculino , Repeticiones de Microsatélite , Reproducción , Túnez , Wolbachia/clasificación
4.
J Clin Microbiol ; 52(1): 268-74, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24226919

RESUMEN

Ticks (n = 663) and fleas (n = 470) collected from domestic animals from southeastern Tunisia were screened for Rickettsia infection using reverse line blot assay. Evidence of spotted fever group Rickettsia was obtained. We detected Rickettsia felis in fleas, Rickettsia massiliae Bar 29 and the Rickettsia conorii Israeli spotted fever strain in ticks, and Rickettsia conorii subsp. conorii and Rickettsia spp. in both arthropods. The sensitivity of the adopted technique allowed the identification of a new association between fleas and R. conorii subsp. conorii species. The presence of these vector-borne Rickettsia infections should be considered when diagnosing this disease in humans in Tunisia.


Asunto(s)
Vectores Artrópodos , Ctenocephalides/microbiología , Rhipicephalus sanguineus/microbiología , Rickettsia/aislamiento & purificación , Animales , Proteínas de la Membrana Bacteriana Externa/genética , ADN Bacteriano/química , ADN Bacteriano/genética , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Túnez
5.
BMC Infect Dis ; 14: 598, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25398483

RESUMEN

BACKGROUND: Our aim is to detect the infection by Toscana virus (TOSV) and other Phleboviruses in the sera and cerebro-spinal fluid (CSF) of patients with meningitis in Tunisia. We examined various species of phlebotomus present in Tunisia to determine whether or not a direct relationship exists between cases of meningitis and the viruses circulating in the insect vectors. METHODS: Patients with the meningeal syndrome were tested for anti-TOSV IgM and IgG using an indirect Enzyme-Linked Immunosorbent Assay (ELISA) and for the presence of TOSV and other Phleboviruses using a RT-PCR test. RESULTS: Of 263 patients were tested using ELISA of which 12.16% (n = 32/263) were IgM positive for anti TOSV. Of these 32 patients, 78% (n = 25/32) were IgG positive. 12.86% (n = 18/140) of the CSF samples tested by RT-PCR were positive for the Toscana virus. CONCLUSIONS: This study confirms, for the first time, that TOSV is involved in a neurological disorder in North Africa. The incidence of this involvement in Tunisia conforms with observations made in other Mediterranean countries. Moreover, for the first time, a molecular approach was used to detect SFSV in a Tunisian patient displaying neurological symptoms.


Asunto(s)
Infecciones por Bunyaviridae/virología , Insectos Vectores/virología , Meningitis/virología , Phlebovirus/aislamiento & purificación , Psychodidae/virología , Virus de Nápoles de la Fiebre de la Mosca de los Arenales/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/líquido cefalorraquídeo , Infecciones por Bunyaviridae/sangre , Infecciones por Bunyaviridae/inmunología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Meningitis/sangre , Meningitis/líquido cefalorraquídeo , Meningitis/inmunología , Persona de Mediana Edad , Datos de Secuencia Molecular , Phlebovirus/inmunología , Virus de Nápoles de la Fiebre de la Mosca de los Arenales/inmunología , Estudios Seroepidemiológicos , Túnez/epidemiología , Adulto Joven
6.
Pathogens ; 12(3)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36986282

RESUMEN

Mosquito-borne diseases have a significant impact on humans and animals and this impact is exacerbated by environmental changes. However, in Tunisia, surveillance of the West Nile virus (WNV) is based solely on the surveillance of human neuroinvasive infections and no study has reported mosquito-borne viruses (MBVs), nor has there been any thorough serological investigation of anti-MBV antibodies in horses. This study therefore sought to investigate the presence of MBVs in Tunisia. Among tested mosquito pools, infections by WNV, Usutu virus (USUV), and Sindbis virus (SINV) were identified in Cx. perexiguus. The serosurvey showed that 146 of 369 surveyed horses were positive for flavivirus antibodies using the cELISA test. The microsphere immunoassay (MIA) showed that 74 of 104 flavivirus cELISA-positive horses were positive for WNV, 8 were positive for USUV, 7 were positive for undetermined flaviviruses, and 2 were positive for tick-borne encephalitis virus (TBEV). Virus neutralization tests and MIA results correlated well. This study is the first to report the detection of WNV, USUV and SINV in Cx. perexiguus in Tunisia. Besides, it has shown that there is a significant circulation of WNV and USUV among horses, which is likely to cause future sporadic outbreaks. An integrated arbovirus surveillance system that includes entomological surveillance as an early alert system is of major epidemiological importance.

7.
Pathogens ; 11(3)2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-35335639

RESUMEN

Anaplasma species are obligate intracellular rickettsial vector-borne pathogens that impose economic constraints on animal breeders and threaten human health. Anaplasma ovis and Anaplasma phagocytophilum infect sheep and goats worldwide. A duplex PCR targeting the msp2 and msp4 genes of A. phagocytophilum and A. ovis, respectively, was developed to analyze the field blood samples collected from sheep and goats. A total of 263 apparently healthy small ruminants from 16 randomly selected flocks situated in 3 bioclimatic zones in Tunisia were analyzed for Anaplasma infections. Anaplasma spp. was detected in 78.3% (95% confidence interval (CI): 72.8-83.1) of the analyzed animals. The prevalence of A. ovis in sheep (80.4%) and goats (70.3%) was higher than that of A. phagocytophilum (7.0% in sheep and 1.6% in goats). Using an inexpensive, specific, and rapid duplex PCR assay, we provide, to the best of our knowledge, the first molecular evidence for the presence of A. phagocytophilum in small ruminants in Tunisia. A. phagocytophilum generally presented as a co-infection with A. ovis. This study provides important data to understand the epidemiology of anaplasmosis in small ruminants, and highlights the risk of contracting the infection upon tick exposure.

8.
Parasit Vectors ; 15(1): 12, 2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-34996507

RESUMEN

BACKGROUND: Leishmaniasis is endemic in Tunisia and presents with different clinical forms, caused by the species Leishmania infantum, Leishmania major, and Leishmania tropica. The life cycle of Leishmania is complex and involves several phlebotomine sand fly vectors and mammalian reservoir hosts. The aim of this work is the development and evaluation of a high-resolution melting PCR (PCR-HRM) tool to detect and identify Leishmania parasites in wild and domestic hosts, constituting confirmed (dogs and Meriones rodents) or potential (hedgehogs) reservoirs in Tunisia. METHODS: Using in vitro-cultured Leishmania isolates, PCR-HRM reactions were developed targeting the 7SL RNA and HSP70 genes. Animals were captured or sampled in El Kef Governorate, North West Tunisia. DNA was extracted from the liver, spleen, kidney, and heart from hedgehogs (Atelerix algirus) (n = 3) and rodents (Meriones shawi) (n = 7) and from whole blood of dogs (n = 12) that did not present any symptoms of canine leishmaniasis. In total, 52 DNA samples were processed by PCR-HRM using both pairs of primers. RESULTS: The results showed melting curves enabling discrimination of the three Leishmania species present in Tunisia, and were further confirmed by Sanger sequencing. Application of PCR-HRM assays on reservoir host samples showed that overall among the examined samples, 45 were positive, while seven were negative, with no Leishmania infection. Meriones shawi were found infected with L. major, while dogs were infected with L. infantum. However, co-infections with L. major/L. infantum species were detected in four Meriones specimens and in all tested hedgehogs. In addition, multiple infections with the three Leishmania species were found in one hedgehog specimen. Sequence analyses of PCR-HRM products corroborated the Leishmania species found in analyzed samples. CONCLUSIONS: The results of PCR-HRM assays applied to field specimens further support the possibility of hedgehogs as reservoir hosts of Leishmania. In addition, we showed their usefulness in the diagnosis of canine leishmaniasis, specifically in asymptomatic dogs, which will ensure a better evaluation of infection extent, thus improving elaboration of control programs. This PCR-HRM method is a robust and reliable tool for molecular detection and identification of Leishmania and can be easily implemented in epidemiological surveys in endemic regions.


Asunto(s)
Reservorios de Enfermedades , Leishmania/aislamiento & purificación , Leishmaniasis/parasitología , Animales , Reservorios de Enfermedades/clasificación , Reservorios de Enfermedades/parasitología , Perros , Enfermedades Endémicas , Gerbillinae/parasitología , Erizos/parasitología , Humanos , Leishmania/genética , Leishmania/crecimiento & desarrollo , Leishmania/patogenicidad , Reacción en Cadena de la Polimerasa , Enfermedades de los Roedores/parasitología , Roedores , Temperatura de Transición , Túnez
9.
Sci Rep ; 12(1): 19310, 2022 11 11.
Artículo en Inglés | MEDLINE | ID: mdl-36369253

RESUMEN

The mitochondrial genome (mitogenome) has proven to be important for the taxonomy, systematics, and population genetics of ticks. However, current methods to generate mitogenomes can be cost-prohibitive at scale. To address this issue, we developed a cost-effective approach to amplify and sequence the whole mitogenome of individual tick specimens. Using two different primer sites, this approach generated two full-length mitogenome amplicons that were sequenced using the Oxford Nanopore Technologies' Mk1B sequencer. We used this approach to generate 85 individual tick mitogenomes from samples comprised of the three tick families, 11 genera, and 57 species. Twenty-six of these species did not have a complete mitogenome available on GenBank prior to this work. We benchmarked the accuracy of this approach using a subset of samples that had been previously sequenced by low-coverage Illumina genome skimming. We found our assemblies were comparable or exceeded the Illumina method, achieving a median sequence concordance of 99.98%. We further analyzed our mitogenome dataset in a mitophylogenomic analysis in the context of all three tick families. We were able to sequence 72 samples in one run and achieved a cost/sample of ~ $10 USD. This cost-effective strategy is applicable for sample identification, taxonomy, systematics, and population genetics for not only ticks but likely other metazoans; thus, making mitogenome sequencing equitable for the wider scientific community.


Asunto(s)
Genoma Mitocondrial , Garrapatas , Humanos , Animales , Genoma Mitocondrial/genética , Filogenia , Garrapatas/genética , Análisis de Secuencia de ADN , Secuenciación de Nucleótidos de Alto Rendimiento/métodos
10.
Parasite ; 29: 45, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36200781

RESUMEN

Accurate identification of insect species is an indispensable and challenging requirement for every entomologist, particularly if the species is involved in disease outbreaks. The European MediLabSecure project designed an identification (ID) exercise available to any willing participant with the aim of assessing and improving knowledge in mosquito taxonomy. The exercise was based on high-definition photomicrographs of mosquitoes (26 adult females and 12 larvae) collected from the western Palaearctic. Sixty-five responses from Europe, North Africa and the Middle East were usable. The study demonstrated that the responders were better at identifying females (82% correct responses) than larvae (63%). When the responders reported that they were sure of the accuracy of their ID, the success rate of ID increased (92% for females and 88% for larvae). The top three tools used for ID were MosKeyTool (72% of responders), the ID key following Becker et al. [2010. Mosquitoes and their control, 2nd edn. Berlin: Springer] (38%), and the CD-ROM of Schaffner et al. [2001. Les moustiques d'Europe: logiciel d'identification et d'enseignement - The mosquitoes of Europe: an identification and training programme. Montpellier: IRD; EID] (32%), while other tools were used by less than 10% of responders. Responders reporting the identification of mosquitoes using the MosKeyTool were significantly better (80% correct responses) than non-MosKeyTool users (69%). Most responders (63%) used more than one ID tool. The feedback from responders in this study was positive, with the exercise being perceived as halfway between educational training and a fun quiz. It raised the importance of further expanding training in mosquito ID for better preparedness of mosquito surveillance and control programmes.


Title: Évaluation de l'expertise en identification morphologique des espèces de moustiques (Diptera, Culicidae) à l'aide de photomicrographies. Abstract: L'identification précise des espèces d'insectes est une exigence indispensable et difficile pour tout entomologiste, en particulier si l'espèce est impliquée dans des épidémies. Le projet européen MediLabSecure a conçu un exercice d'identification (ID) accessible à tout participant volontaire dans le but d'évaluer et d'améliorer les connaissances en taxonomie des moustiques. L'exercice était basé sur des photomicrographies haute définition de moustiques (26 femelles adultes et 12 larves) prélevées dans le Paléarctique occidental. Soixante-cinq réponses d'Europe, d'Afrique du Nord et du Moyen-Orient ont été utilisables. L'étude a démontré que les répondants étaient meilleurs pour identifier les femelles (82 % de réponses correctes) que les larves (63 %). Lorsque les répondants ont déclaré être sûrs de l'exactitude de leur ID, le taux de réussite de l'identification était meilleur (92 % pour les femelles et 88 % pour les larves). Les trois principaux outils utilisés pour les ID étaient MosKeyTool (72 % des répondants), la clé d'identification du livre de Becker et al. (38%) et le CD-ROM de Schaffner et al. (32 %), tandis que d'autres outils étaient utilisés par moins de 10 % des répondants. Les répondants déclarant identifier des moustiques à l'aide de MosKeyTool étaient significativement meilleurs (80 % de réponses correctes) que les non-utilisateurs de MosKeyTool (69 %). La plupart des répondants (63 %) ont utilisé plus d'un outil d'identification. Les commentaires des répondants de cette étude ont été positifs, l'exercice étant perçu comme à mi-chemin entre une formation pédagogique et un quiz amusant. Il a souligné l'importance d'étendre la formation complémentaire à l'identification des moustiques pour une meilleure préparation des programmes de surveillance et de contrôle des moustiques.


Asunto(s)
Culicidae , África del Norte , Animales , Brotes de Enfermedades , Europa (Continente) , Femenino , Humanos , Larva , Mosquitos Vectores
11.
Vet Parasitol Reg Stud Reports ; 23: 100512, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33678367

RESUMEN

A paucity of studies is available on haemoparasites in dogs in Tunisia. In this study, we used molecular techniques (PCR/sequencing) to detect and characterize haemoprotozoa in sick dogs from Tunisia. A total of 99 dogs displaying such clinical symptoms as fever, anorexia, and depression were presented for treatment to the hospital of the Veterinary School of Sidi Thabet (Tunisia). Among dogs screened by PCR, five (5%) proved to be infected with a hemoprotozoa species. An analysis of all the sequences that were obtained enabled us to identify two species of Protozoa: Babesia vogeli (in three dogs) and Hepatozoon canis (in two other dogs). This is the first time that an infection of dogs by Hepatozoon canis in Tunisia has been reported. Veterinary practitioners should be aware that these two haemoparasites can infect dogs and should include them in any differential diagnosis of clinical illnesses with manifestations compatible with tick-borne diseases.


Asunto(s)
Babesiosis , Coccidiosis/veterinaria , Enfermedades de los Perros , Animales , Babesia/clasificación , Babesiosis/diagnóstico , Babesiosis/epidemiología , Coccidiosis/diagnóstico , Coccidiosis/epidemiología , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Perros/parasitología , Eucoccidiida/clasificación , Túnez/epidemiología
12.
Pathogens ; 10(6)2021 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-34207423

RESUMEN

Crimean-Congo hemorrhagic fever virus (CCHFV, Nairoviridae family) and Rift Valley fever virus (RVFV, Phenuiviridae family) are zoonotic vector-borne pathogens with clinical relevance worldwide. Our study aimed to determine seroprevalences of these viruses and potential risk factors among livestock (cattle, sheep, and goats) in Tunisia. Sera were tested for antibodies against CCHFV (n = 879) and RVFV (n = 699) using various enzyme-linked immunosorbent assays (ELISAs) and indirect immunofluorescence assays (IIFA). The overall seroprevalence of IgG antibodies was 8.6% (76/879) and 2.3% (16/699) against CCHFV and RVFV, respectively. For CCHF seropositivity bioclimatic zones and breed were potential risk factors for the three tested animal species; while the season was associated with cattle and sheep seropositivity, tick infestation was associated with cattle and goats seropositivity and age as a risk factor was only associated with cattle seropositivity. Age and season were significantly associated with RVFV seropositivity in sheep. Our results confirm the circulation of CCHFV and RVFV in Tunisia and identified the principal risk factors in ruminants. This knowledge could help to mitigate the risk of ruminant infections and subsequently also human infections.

13.
PLoS Negl Trop Dis ; 15(12): e0009990, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34890393

RESUMEN

BACKGROUND: Discovered by Nicolle and Comte in 1908 in Tunisia, Leishmania infantum is an intracellular protozoan responsible for zoonotic canine leishmaniosis (CanL) and zoonotic human visceral leishmaniasis (HVL). It is endemic in several regions of the world, including Tunisia, with dogs considered as the main domestic reservoir. The geographic expansion of canine leishmaniosis (CanL) has been linked to global environmental changes that have affected the density and the distribution of its sand fly vectors. METHODOLOGY/PRINCIPAL FINDINGS: In this study, a cross-sectional epidemiological survey on CanL was carried out in 8 localities in 8 bioclimatic areas of Tunisia. Blood samples were taken from 317 dogs after clinical examination. Collected sera were tested by indirect fluorescent antibody test (IFAT; 1:80) for the presence of anti-Leishmania infantum antibodies. The overall seroprevalence was 58.3% (185/317). Among positive dogs, only 16.7% showed clinical signs suggestive of leishmaniosis. Seroprevalence rates varied from 6.8% to 84.6% and from 28% to 66% by bioclimatic zone and age group, respectively. Serological positivity was not statistically associated with gender. The presence of Leishmania DNA in blood, using PCR, revealed 21.2% (64/302) prevalence in dogs, which varied by bioclimatic zone (7.3% to 31%) and age group (7% to 25%). The entomological survey carried out in the studied localities showed 16 species of the two genera (Phlebotomus and Sergentomyia). P. perniciosus, P. papatasi, and P. perfiliewi were the most dominant species with relative abundances of 34.7%, 25% and 20.4%, respectively. CONCLUSIONS/SIGNIFICANCE: The present report suggests a significant increase of CanL in all bioclimatic areas in Tunisia and confirms the ongoing spread of the infection of dogs to the country's arid zone. Such an expansion of infection in dog population could be attributed to ecological, agronomic, social and climatic factors that affect the presence and density of the phlebotomine vectors.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/inmunología , Leishmania infantum/inmunología , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/veterinaria , Animales , Estudios Transversales , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/transmisión , Perros , Femenino , Insectos Vectores/clasificación , Insectos Vectores/parasitología , Leishmania infantum/genética , Leishmania infantum/patogenicidad , Leishmaniasis Visceral/inmunología , Leishmaniasis Visceral/transmisión , Masculino , Phlebotomus/parasitología , Prevalencia , Estudios Seroepidemiológicos , Túnez/epidemiología
14.
Pathogens ; 10(8)2021 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-34451417

RESUMEN

Small wild mammals are an important element in the emergence and transmission of vector-borne pathogens (VBPs). Among these species, hedgehogs have been found to be a reservoir of VBPs and host of arthropod vectors. Surveillance of VBPs in wildlife and their arthropods are crucial in a one health context. We conducted an exploratory study to screen Atelerix algirus hedgehogs and their infesting ticks and fleas for VBPs using a high throughput microfluidic real-time PCR system. Tested biopsies from hedgehogs were found to be naturally infected by Theileria youngi, Hepatozoon sp., Ehrlichia ewingii, Coxiella burnetii, and Candidatus Ehrlichia shimanensis. Similarly, Haemaphysalis erinacei and Rhipicephalus sanguineus tick species were infected by Ehrlichia ewingii, Rickettsia spp., Rickettsia massiliae, Borrelia sp., Coxiella burnetii, Rickettsia lusitaniae and Anaplasma sp. Archaeopsylla erinacei fleas were infected by Rickettsia asembonensis, Coxiella burnetii, and Rickettsia massiliae. Co-infections by two and three pathogens were detected in hedgehogs and infesting ticks and fleas. The microfluidic real-time PCR system enabled us not only to detect new and unexpected pathogens, but also to identify co-infections in hedgehogs, ticks, and fleas. We suggest that hedgehogs may play a reservoir role for VBPs in Tunisia and contribute to maintaining enzootic pathogen cycles via arthropod vectors.

15.
Toxins (Basel) ; 13(12)2021 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-34941750

RESUMEN

Hemostatic disorders are caused either by platelet-related dysfunctions, defective blood coagulation, or by a combination of both, leading to an increased susceptibility to cardiovascular diseases (CVD) and other related illnesses. The unique specificity of anticoagulants from hematophagous arthropods, such as ticks, suggests that tick saliva holds great promise for discovering new treatments for these life-threatening diseases. In this study, we combined in silico and in vitro analyses to characterize the first recombinant serpin, herein called Dromaserpin, from the sialotranscriptome of the Hyalomma dromedarii tick. Our in silico data described Dromaserpin as a secreted protein of ~43 kDa with high similarities to previously characterized inhibitory serpins. The recombinant protein (rDromaserpin) was obtained as a well-structured monomer, which was tested using global blood coagulation and platelet aggregation assays. With this approach, we confirmed rDromaserpin anticoagulant activity as it significantly delayed plasma clotting in activated partial thromboplastin time and thrombin time assays. The profiling of proteolytic activity shows its capacity to inhibit thrombin in the micromolar range (0.2 to 1 µM) and in the presence of heparin this inhibition was clearly increased. It was also able to inhibit Kallikrein, FXIa and slightly FXIIa, with no significant effect on other factors. In addition, the rDromaserpin inhibited thrombin-induced platelet aggregation. Taken together, our data suggest that rDromaserpin deserves to be further investigated as a potential candidate for developing therapeutic compounds targeting disorders related to blood clotting and/or platelet aggregation.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Ixodidae/metabolismo , Serpinas/química , Serpinas/farmacología , Secuencia de Aminoácidos , Animales , Anticoagulantes/química , Anticoagulantes/metabolismo , Simulación por Computador , Modelos Moleculares , Filogenia , Conformación Proteica , Serpinas/metabolismo
16.
PLoS Negl Trop Dis ; 14(10): e0008475, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33007002

RESUMEN

The mosquito Aedes albopictus was detected for the first time in Tunisia in 2018. With its establishment in the capital city of Tunis, local health authorities fear the introduction of new human arboviral diseases, like what happened in Europe with unexpected local cases of chikungunya, dengue and Zika. Even though this mosquito is competent to transmit the arboviruses mentioned above, the transmission level will vary depending on the couple, mosquito population and virus genotype. Here, we assessed the vector competence of Ae. albopictus Tunisia by experimental infections with chikungunya (CHIKV), dengue (DENV), and Zika (ZIKV) viruses. We found that Ae. albopictus Tunisia was highly competent for CHIKV (transmission efficiency of 25% at 21 post-infection) and to a lesser extent, for ZIKV (8.7%) and DENV (8.3%). Virus was detected in mosquito saliva at day 3 (CHIKV), day 10 (ZIKV) and day 21 (DENV) post-infection. These results suggest that the risk of emergence of chikungunya is the highest imposing a more sustained surveillance to limit Ae. albopictus populations in densely populated urban dwellings and at the entry points of travelers returning from CHIKV-endemic regions.


Asunto(s)
Aedes/virología , Fiebre Chikungunya/transmisión , Dengue/transmisión , Mosquitos Vectores/virología , Infección por el Virus Zika/transmisión , Animales , Línea Celular , Virus Chikungunya , Chlorocebus aethiops , Virus del Dengue , Femenino , Masculino , Conejos , Saliva/virología , Túnez , Células Vero , Virus Zika
17.
Emerg Infect Dis ; 15(10): 1626-9, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19861058

RESUMEN

We found that 20.5% of patients with an unexplained fever in northwestern Morocco had tick-borne relapsing fever. Molecular detection specific for the 16S rRNA gene identified Borrelia hispanica. The noncoding intergenic spacer sequence domain showed high sensitivity and good resolution for this species.


Asunto(s)
Borrelia/genética , Fiebre Recurrente/epidemiología , Fiebre Recurrente/microbiología , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , Borrelia/clasificación , Borrelia/aislamiento & purificación , Humanos , Marruecos/epidemiología , Filogenia , ARN Ribosómico 16S/genética
18.
J Med Entomol ; 56(4): 1112-1115, 2019 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-31220308

RESUMEN

Aedes albopictus (Skuse) is a widespread invasive mosquito vector species with a distribution including tropical and temperate climates; its range is still expanding. Aedes albopictus populations were recently detected in Morocco and Algeria, the countries neighboring Tunisia, but never in Tunisia. In 2018, we initiated an intensive field study using BG-Sentinel Traps, ovitraps, larval surveys, and citizens' reports to determine whether Ae. albopictus populations exist in Tunisia. In October 2018, we collected adults and larval stages of Ae. albopictus in Carthage, Amilcar, and La Marsa, less than 20 km, northeast of Tunis, the Tunisian capital. These Ae. albopictus larvae were primarily collected from Phoenician funeral urns at the archeological site of Carthage. This is, to our knowledge, the first detection of Ae. albopictus in Tunisia.


Asunto(s)
Aedes , Distribución Animal , Animales , Túnez
19.
J Med Entomol ; 56(5): 1377-1383, 2019 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-31121045

RESUMEN

The present study aimed to update the list of Aedes mosquito species occurring in Tunisia and to test the vector competence of Aedes (Ochlerotatus) caspius (Pallas) and Ae. (Ochlerotatus) detritus (Haliday), the locally most abundant and widespread species, to transmit Zika virus (ZIKV). In 2017-2018, mosquito larvae were collected from 39 different larval habitats in seven bioclimatic zones of Tunisia. The salinity and pH of each breeding site were measured. The survey revealed the presence of 10 Aedes species in Tunisia: Ae. (Stegomyia) albopictus (Skuse), Ae. (Ochlerotatus) berlandi (Séguy), Ae. caspius, Ae. detritus, Ae. (Finlaya) echinus (Edwards), Ae. (Finlaya) geniculatus (Olivier), Ae. (Acartomyia) mariae (Sergent and Sergent), Ae. (Ochlerotatus) pulcritarsis (Rondani), Ae. (Aedimorphus) vexans (Meigen), and Ae. (Fredwardsius) vittatus (Bigot). Of these 10 species, Ae. caspius and Ae. detritus were the most abundant in Tunisia. Aedes detritus and Ae. caspius larvae were reared until the imago stage under insectary conditions to test autogeny. The study showed that Ae. detritus is autogenous and stenogamous and Ae. caspius, anautogenous and eurygamous. Finally, the collected strains of these two species were experimentally infected with the Asian genotype of ZIKV, originally isolated from a patient in April 2014 in New Caledonia, to test their vector competence. Neither of these species was able to transmit ZIKV at 7 and 14 d postexposure. Further investigations are needed to test the competence of other Tunisian mosquito species that may be associated with ZIKV transmission.


Asunto(s)
Mosquitos Vectores/parasitología , Ochlerotatus/parasitología , Infección por el Virus Zika/transmisión , Virus Zika/fisiología , Aedes/crecimiento & desarrollo , Aedes/parasitología , Animales , Femenino , Larva , Ochlerotatus/crecimiento & desarrollo , Túnez
20.
Ticks Tick Borne Dis ; 10(1): 219-240, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30309738

RESUMEN

The systematics of the genera and subgenera within the soft tick family Argasidae is not adequately resolved. Different classification schemes, reflecting diverse schools of scientific thought that elevated or downgraded groups to genera or subgenera, have been proposed. In the most recent classification scheme, Argas and Ornithodoros are paraphyletic and the placement of various subgenera remains uncertain because molecular data are lacking. Thus, reclassification of the Argasidae is required. This will enable an understanding of soft tick systematics within an evolutionary context. This study addressed that knowledge gap using mitochondrial genome and nuclear (18S and 28S ribosomal RNA) sequence data for representatives of the subgenera Alectorobius, Argas, Chiropterargas, Ogadenus, Ornamentum, Ornithodoros, Navis (subgen. nov.), Pavlovskyella, Persicargas, Proknekalia, Reticulinasus and Secretargas, from the Afrotropical, Nearctic and Palearctic regions. Hard tick species (Ixodidae) and a new representative of Nuttalliella namaqua (Nuttalliellidae), were also sequenced with a total of 83 whole mitochondrial genomes, 18S rRNA and 28S rRNA genes generated. The study confirmed the utility of next-generation sequencing to retrieve systematic markers. Paraphyly of Argas and Ornithodoros was resolved by systematic analysis and a new species list is proposed. This corresponds broadly with the morphological cladistic analysis of Klompen and Oliver (1993). Estimation of divergence times using molecular dating allowed dissection of phylogeographic patterns for argasid evolution. The discovery of cryptic species in the subgenera Chiropterargas, Ogadenus and Ornithodoros, suggests that cryptic speciation is common within the Argasidae. Cryptic speciation has implications for past biological studies of soft ticks. These are discussed in particular for the Ornithodoros (Ornithodoros) moubata and Ornithodoros (Ornithodoros) savignyi groups.


Asunto(s)
Argasidae/clasificación , Especiación Genética , Genoma Mitocondrial/genética , Animales , Argas/clasificación , Argas/genética , Argasidae/genética , Clasificación , Código de Barras del ADN Taxonómico , ADN Ribosómico/química , ADN Ribosómico/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Ornithodoros/clasificación , Ornithodoros/genética , Filogenia , ARN Ribosómico 18S/genética , ARN Ribosómico 28S/genética , Análisis de Secuencia de ADN
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