Abstract
Yellow fever, dengue (types 1, 2 and 4), Chikungunya, Rift Valley fever, Ebola, Marburg, and Lassa viruses were inoculated into susceptible cell cultures and daily investigated by indirect immunofluorescence (IFA) and electron microscopy (EM) with a view to achive an early detection-identification of these agents. Compared to the other cell lines tested (Vero, BHK-21 and Aedes albopictus ), CV-1 cells were found to be more sensitive. Viral antigens were detected by IFA from a few hours post inoculation (CHIK and RVF) to a maximum of 3 days (YF and EBO). For most of the viruses studied, the cytopathic effect (CPE) commened 2-3 days after the detection of viral antigens. Virus particles were detected by EM only in the case of EBO, MBG and LAS, before any CPE was observed in cell cultures.