ABSTRACT
Les meningites a Toscana Virus ont ete largement decrites en Italie ou le virus a ete isole pour la premiere fois. Actuellement; elles sont de plus en plus decrites dans le pourtour du bassin mediterraneen devenant ainsi une pathologie emergente dans cette region. Nous rapportons; dans ce travail; 4 cas de meningites a Toscana Virus hospitalises dans le service des Maladies Infectieuses de l'hopital Fattouma Bourguiba de Monastir - Tunisie; en rappelant les caracteristiques epidemiologiques; cliniques; biologiques et evolutives. Tous les malades etaient de sexe masculin; demeurant dans une region cotiere et hospitalises pendant la saison estivale. Ils etaient ages en moyenne de 26 ans (14 - 41). Le diagnostic clinique reposait sur la presence d'un syndrome meninge febrile. La ponction lombaire avait montre dans les 4 cas une meningite lymphocytaire a liquide clair avec une glycorrachie normale. La detection des IgM et des IgG dans le sang et le LCR avait permis de confirmer le diagnostic. L'evolution etait favorable sous traitement symptomatique; dans tous les cas; avec un recul de 9 mois
Subject(s)
Meningitis, Viral , PhlebotomusABSTRACT
Background. Leishmaniasis is a vector-borne disease in which Leishmania parasites are transmittedby the bite of phlebotomine sand flies. Amastigotes are ingested by the sand fly vector with ablood meal taken from an infected host. This is followed by their differentiation into metacyclicpromastigotes which are selectively released and permitted to migrate interiorly so as to makethem available for transmission by bite. However, the actual number of amastigotes ingested bythe sand fly in the blood meal is not known.Objective: Toinvestigate the minimum number of Leishmania major amastigotes required to causean infection in Phlebotomus duboscqi following an infective blood meal.Design: A laboratory based study.Setting: Centre for Biotechnology Research and Development, Kenya Medical Research institute, Nairobi.Results: Dissection of all fed sand flies at six days post-infective blood meal revealed that bloodcontaining one amastigote per 0.3µl in a total volume of 0.5ml was able to cause an infection in thesand flies, but very few sand flies got infected (7.6% and 9.6% respectively). Concentrations of tenamastigotes per 0.3µl in 0.5ml gave infection rates of 35.4% and 26.3% respectively, suggesting thateven when the concentration of amastigotes in a bloodmeal was high, not all sand flies feeding onit were able to pick up the parasites.Conclusions:These observations suggests that one amastigote is sufficient to cause an infection toa sand fly and as a result of multiplication in the gut and the existence of mechanisms that increasethe number of infective bites delivered by a female sand fly they are able to sustain the transmissionof leishmaniasis in an area
Subject(s)
Leishmania , Parasitic Diseases , PhlebotomusABSTRACT
The abundance of phlebotomine sandflies was studied in a leishmaniasis endemic area in Baringo District; Rift Valley Province; Kenya. This was based on sandfly behaviors at night in their natural habitats of termite hills and animal burrows. Sandflies were collected with an entry-exit trap which has a sieve fixed at the middle to control sandfly movements. Flies were trapped from 1800-0600 hours. Phlebotomus martini (Parrot) were significantly more abundant in termite hills than in animal burrows (P 0.05). Phlebotomus duboscqi (Neveu-Lemaire) were found to favour animal burrows more than termite hills (P 0.05). Nocturnal movements and activities showed that the majority of the sandflies were exiting from termite hills and animal burrows from 1800-2400 hours while from 2400-0600 hours; the majority of the sandflies were entering termite hills and animal burrows (P0.05). Sergentomyia (Theodor) species showed mixed preferences for these two habitats. Sergentomyia schwetzi (Aldler; Theodor et Pam favoured termite hills more than animal burrows but S. clydei (Sinton) showed great preference for animal burrows. The nocturnal activities or preferences of habitats by phlebotomine sandflies have epidemiological significance in that control measures can be directed to these habitats with a certain degree of accuracy for the vectors of visceral and cutaneous Leishmaniasis in Kenya
Subject(s)
Diptera , Leishmaniasis , Phlebotomus , PsychodidaeABSTRACT
Background. Research in our laboratory has previously shown that immune-mediated transmission blocking may be applied to Leishmania infections and that the LPG molecule and anti-LPG monoclonal antibodies was found to be an excellent candidate against L. major infections. Objective: To test the effect of monoclonal antibodies (MABs) raised against different species ofLeishmania for their ability to inhibit development of Leishmania major in Phlebotomus duboscqi sand flies. Design: A laboratory based study. Setting: Centre for Biotechnology Research and Development; Kenya Medical Research Institute; Nairobi. Results: Sand fly dissections on days two; four and six post-feeding showed that monoclonal antibodies against L. donovani (Ld2cb and Ld3A3) were the most effective at inhibiting L. major development than those raised against L. aethiopica; L. major or L. tropica. Ld2cb inhibited L. major development by 82