Serum Antibodies Reactant with Korean Haemorrhagic Fever Agent in Scandinavian Epidemic (Endemic) Nephropathy (Nephropathia Epidemica) Demonstrated by Immunofluorescence Utilizing an in vitro Antigen Source

Abstract

A newly developed spot slide immunofluorescence method utilizing an in vitro antigen source was used for the 1st time for the assay of antibodies reactive with the Korean hemorrhagic fever (KHF) agent in sera from patients diagnosed with Scandinavian epidemic (endemic) nephropathy (nephropathia epidemica, NE) and from age-matched control patients living in the same area as the NE patients but suffering from other diseases. KHF antibodies were demonstrated in all of 14 NE patients who were followed prospectively, 7 of whom exhibited seroconversion, and in 6 of 8 NE patients studied retrospectively, but in only 1 of 42 controls. Antibodies in NE appeared within the 1st wk of onset of symptoms and persisted for long times. The time from the onset of the illness until maximum antibody titer varied from 9 days-1 mo. On an average, the level of the antibody titers measured in NE was lower than that usually encountered in the Korean disease. A close antigenic relationship between the KHF and NE agents was suggested. The reliability of this new spot slide method is apparently similar to that of another previously reported and more laborious immunofluorescence methd using lung from infected rodents as antigen source.