ELISA for the detection of antibodies to Ebola viruses

EIAs for Ige and IgM antibodies directed against Ebola (EBO) viral antigens have been developed and evaluated using sera of animals and humans survivi ng infection with EBO viruses. The IgM capture assay detected anti-EBO (sub type Reston) antibodies in the sera of 5 of 5 experimentally infected anima ls at the time they succumbed to lethal infections. IgM antibodies were als o detected in the serum of a human who was infected with EBO (subtype Resto n) during a postmortem examination of an infected monkey. The antibody was detectable as early as day 6 after infection in experimentally infected ani mals and persisted for <90 days. The IgG response was less rapid; however, it persisted for >400 days in 3 animals who survived infection, and it pers isted for similar to 10 years after infection in the sera of 2 humans. Alth ough these data are limited by the number of sera available for verificatio n, the IgM assay seems to have great promise as a diagnostic tool. Furtherm ore the long-term persistence of the IgG antibodies measured by this test s trongly suggests that the ELISA will be useful in field investigations of E BO virus.