ABSTRACT
A combination of interview, serology and skin testing was used to investigate the status of apparently healthy villagers during a visceral leishmaniasis epidemic in southern Sudan. The number of people who had died equalled the number who were alive at the time of the survey. The direct agglutination test (DAT) identified 10% of the people as being serologically positive. Most young children (36/39) and 34% (22/64) of adults had neither positive serology nor skin test. About 64% (42/66) of adults had positive skin tests. In two villages, 54% and 76% of those over four years of age showed evidence of having been infected. The mortality associated with infection was estimated as at least 69%; 25% of those infected appeared to have cured spontaneously. The outcome for the remaining 6% was still doubtful. Even in this devastating epidemic there is, therefore, evidence of a considerable amount of infection without severe disease. Serological tests, while useful clinically, are apparently not useful for detecting early cases. Combined skin testing and serology produces a comprehensive though partially hypothetical picture.
Subject(s)
Disease Outbreaks , Leishmaniasis, Visceral/mortality , Adolescent , Adult , Age Factors , Agglutination Tests , Child , Child, Preschool , Female , Humans , Infant , Leishmaniasis, Visceral/diagnosis , Leishmaniasis, Visceral/immunology , Male , Rural Population , Sex Factors , Skin Tests , Sudan/epidemiologyABSTRACT
Twenty-five strains of Leishmania donovani isolated from humans and Phlebotomus orientalis in an epidemic area of southern Sudan were shown to belong to 3 very similar zymodemes: MON 18 (11 strains), MON 30 (1 strain) and MON 82 (13 strains). The 3 zymodemes are very closely related and seem to behave as a single population.
Subject(s)
Disease Outbreaks , Leishmania donovani/classification , Leishmaniasis, Visceral/epidemiology , Animals , Humans , Leishmania donovani/isolation & purification , Leishmaniasis, Visceral/parasitology , Phlebotomus/parasitology , Sudan/epidemiologyABSTRACT
The complete spermathecae of 13 species of Larroussius were dissected and examined. The base of the duct of 4 species (aculeatus, guggisbergi, tobbi, wui) is bell-shaped: they are easily distinguished by differences in shape. Five other species (perniciosus, pedifer, longicuspis, perfiliewi, galilaeus) have lateral structures at the base of the duct: slight differences between perniciosus, pedifer and longicuspis distinguish these species: the structures of perfiliewi and galilaeus are the same. Species of a third group (neglectus, syriacus) have a common duct with no lateral structures: they are distinguishable by minor differences. Two species (ariasi, orientalis) from a fourth group with expanded distal parts of the duct; the size and shape of the expanded parts easily separates the species. The study shows a great variation in the morphology of the base of the spermathecal ducts of Larroussius and confirms the value of this feature in identifying otherwise indistinguishable females of the subgenus.
