RESUMEN
An inter-epidemic oversight was conducted in the cutaneous leishmaniasis focus of Keur Moussa (Thies region) between June 2015 and October 2016, more than 20 years after the last epidemic. The three sampling methods (adhesive traps, CDC light traps, and indoor pyrethroids sprays) allowed the capture of 1,746 sand flies belonging to 2 genera and 24 species, those involved in the transmission of leishmaniasis in Senegal, as well as 11 new species for the focus. The vector of human cutaneous leishmaniasis in Senegal, Phlebotomus duboscqi Neveu-Lemaire, 1906, represents 10.9% of this fauna. Sergentomyia schwetzi, one of the species involved, with Sergentomyia dubia and Sergentomyia magna, in the transmission of canine leishmaniasis in Senegal, is the most abundant species with 38.1% of the samples. The other two species have individually smaller percentages. Seasonal variations of the abundance show an intense activity of sandflies at the end of the dry season under the influence of high average temperatures and a humidity exceeding 50%. Rains are a limiting factor. According to the enrichment of the fauna and the high density of the different vectors of leishmaniasis in this focus, particularly P. duboscqi, a specific importance should be given for this focus in order to prevent occurrence of epidemics.
Une surveillance interépidémique a été menée au niveau du foyer de leishmaniose cutanée de Keur Moussa (région de Thiès) entre juin 2015 et octobre 2016, soit plus de 20 ans après la dernière épidémie. Les trois méthodes d'échantillonnage utilisées (papiers huilés, pièges lumineux CDC et pulvérisations intradomiciliaires avec des pyréthrinoïdes) ont permis la capture de 1 746 phlébotomes appartenant à deux genres et 24 espèces, celles impliquées dans la transmission des leishmanioses au Sénégal et 11 espèces nouvelles pour le foyer. Le vecteur de la leishmaniose cutanée humaine au Sénégal, Phlebotomus duboscqi Neveu-Lemaire, 1906, représente 10,9 % des captures. Sergentomyia schwetzi, l'une des espèces impliquées, avec Sergentomyia dubia et Sergentomyia magna, dans la transmission de la leishmaniose canine au Sénégal, est la plus abondante avec 38,1 % des captures. Les deux autres espèces ont des pourcentages individuels moins importants. Les variations saisonnières d'abondance montrent une intense activité des phlébotomes en fin de saison sèche sous l'influence des températures moyennes élevées et d'une humidité dépassant les 50 %. La pluie constitue un facteur limitant. En vue de prévenir la survenue d'épidémies, une importance particulière devra être accordée à ce foyer, vu l'enrichissement de la faune et les densités élevées des différents vecteurs de leishmanioses dans ce foyer, en particulierP. duboscqi.
Asunto(s)
Biodiversidad , Reservorios de Enfermedades/estadística & datos numéricos , Psychodidae , Estaciones del Año , Animales , Demografía , Femenino , Humedad , Insectos Vectores/clasificación , Leishmaniasis Cutánea/transmisión , Masculino , Phlebotomus/clasificación , Psychodidae/clasificación , Lluvia , Senegal/epidemiología , Razón de MasculinidadRESUMEN
A supervision of the focus of human cutaneous leishmaniasis of Keur Moussa has been carried out in 1988-1989 and in 1991-1992. Among the 13 species gathering the 10,144 phlebotomine sandflies trapped, two belong to genus Phlebotomus, the others to genus Sergentomyia. Phlebotomus duboscqi, that has been found out by Deded et al. in 1980 as the vector of this leishmaniasis in Senegal, is the most represented species after Sergentomyia schwetzi, with respectively 32.3 and 28.5% of the found during these two periods. It is twice more abundant and frequent in the monastery area than the religious one. This difference may be due to the better micro-climatic conditions, the abundance of rodents and the human proximity. After the rainy seasons that influence a lot P. duboscqi's activity, the density of phlebotomine sandflies makes a progressive rise, as well as the temperature and humidity, to reach two maxima in April-May and July-August. Parasitological studies on females of phlebotomine sandflies and rodents Arvicanthis niloticus, Mastomys erythroleucus and Cricetomys gambianus are negative. This focus seems to be again in an inter-epidemic phase.
Asunto(s)
Reservorios de Enfermedades , Insectos Vectores/clasificación , Leishmaniasis Cutánea/epidemiología , Muridae/parasitología , Psychodidae/clasificación , Animales , Femenino , Humanos , Humedad , Insectos Vectores/crecimiento & desarrollo , Insectos Vectores/parasitología , Leishmaniasis Cutánea/transmisión , Psychodidae/crecimiento & desarrollo , Psychodidae/parasitología , Lluvia , Enfermedades de los Roedores/epidemiología , Estaciones del Año , Senegal/epidemiología , TemperaturaRESUMEN
In the context of global warming and the risk of spreading arthropod-borne diseases, the emergence and reemergence of leishmaniasis should not be neglected. In Senegal, over the past few years, cases of canine leishmaniasis have been observed. We aim to improve the understanding of the transmission cycle of this zoonosis, to determine the responsible species and to evaluate the risk for human health. An epidemiological and serological study on canine and human populations in the community of Mont Rolland (Thiès area) was conducted. The data showed a high seroprevalence of canine leishmaniasis (>40%) and more than 30% seropositive people. The dogs' seroprevalence was confirmed by PCR data (concordance > 0.85, Kappa > 0.7). The statistical analysis showed strong statistical associations between the health status of dogs and seropositivity, the number of positive PCRs, clinical signs and the number of Leishmania isolates. For the first time, the discriminative PCRs performed on canine Leishmania strains clearly evidenced that the pathogenic agent is Leishmania infantum. The results obtained show that transmission of this species is well established in this area. That the high incidence of seropositivity in humans may be a consequence of infection with this species is discussed.
Asunto(s)
Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Leishmania infantum/aislamiento & purificación , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/veterinaria , Zoonosis/epidemiología , Zoonosis/transmisión , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Niño , Preescolar , ADN Protozoario/genética , Enfermedades de los Perros/transmisión , Perros , Femenino , Humanos , Lactante , Leishmania , Leishmania infantum/genética , Leishmaniasis Visceral/parasitología , Leishmaniasis Visceral/transmisión , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Medición de Riesgo , Senegal/epidemiología , Estudios Seroepidemiológicos , Adulto JovenRESUMEN
During a brief entomological survey carried out in Ouagadougou, Burkina Faso, in March 2002, 178 phlebotomine sand flies (Diptera, Psychodidae) were caught using CDC miniature light traps. They were identified as Phlebotomus duboscqi Neveu-Lemaire, P. longicuspis Nitzulescu, Sergentomyia adleri (Theodor), S. affinis vorax (Parrot), S. antennata (Newstead), S. bedfordi (Newstead), S. christophersi (Sinton), S. fallax (Parrot), S. magna (Sinton) and S. schwetzi (Adler, Theodor & Parrot). This is the first record south of the Sahara of P. longicuspis sensu lato. This proven vector of Leishmania infantum Nicolle is a species closely related to P. perniciosus. It was identified by morphology and by the sequencing of a fragment of mitochondrial cytochrome b. There was 100% sequence homology with typical Tunisian specimens, and all characters identified the specimen as P. longicuspis sensu stricto. Epidemiological and biogeographical consequences are discussed.