EVIDENCE FOR OCCURRENCE OF FILOVIRUS ANTIBODIES IN HUMANS AND IMPORTED MONKEYS - DO SUBCLINICAL FILOVIRUS INFECTIONS OCCUR WORLDWIDE

In the present serologocal study 120 monkey sera from different specie s originating from the Philippines, China, Uganda and undetermined sou rces and several groups of human sera comprising a total of 1288 speci mens from people living in Germany were examined for the presence of a ntibodies directed against filoviruses (Marburg virus, strain Musoke/E bola virus, subtype Zaire, strain Mayinga/Reston virus). Sera were scr eened using a filovirus-specific enzymelinked immunosorbent assay (ELI SA). ELISA-positive sera were then confirmed by the indirect immunoflu orescence technique, Western blot technique, and a blocking assay, and declared positive when at least one cornfirmation test was reactive. Altogether 43.3% of the monkey sera and 6.9% of the human sera reacted positively with at least one of the three different filovirus antigen s. The blocking assays show that antibodies, detected in the sera, are directed to specific filovirus antigens and not caused by antigenic c ross-reactivity with hitherto unknown agents. Data presented in this r eport suggest that subclinical filovirus infections may also occur in humans and in subhuman primates. They further suggest that filoviruses are not restricted to the African continent.