Preliminary Studies on the Endemicity of Arenavirus Infections in Tanzania

Abstract

Field and commensal rodents were live-trapped from various parts of Morogpro, Igunga, Kilwa, Liwale, Nachingwea and Lindi Districts from 1983 to 1985. Cardiac blood was recovered from each captured M.natalensis and serum was separated and preserved at 0-4C and later at -20C at the laboratory. The sera werev tested against Lassa and Mopeia viruses using the indirect immunofluorescence antibody technique. A total of 395 sera were tested. Of these, 17 (4.3%) mostly collected from August to October reacted positively with both viruses at a dilution ranging from 1:8 to 1:256. In 11 out of 17 positive sera, titers were significantly higher against Mopeia than Lassa. Differentiation of the two viruses was not possible as they are antigenically related and hence tend to cross react in the immunofluorescence test. The observations generally suggested that the multmammate rat populations in question carried Arena viruses of some type but further investigation were desirable in order to further characterize it and determine it and determine its distribution pattern, possible seasonality and pathogenicity