title: Detection of nephropathia epidemica (Puumala virus)-specific immunoglobulin M by enzyme-linked immunosorbent assay.
abstract: Nephropathia epidemica (NE), a less severe form of hemorrhagic fever with renal syndrome, is caused by Puumala virus (PUU). This communication reports the development of a mu-capture enzyme-linked immunosorbent assay (ELISA) for detection of specific immunoglobulin M (IgM) antibodies to PUU virus in human sera. Acute- and early-convalescent-phase sera (collected 1 to 41 days after disease onset) from 29 Swedish patients with clinical NE were tested for PUU virus-specific IgG and IgM antibodies by the indirect immunofluorescence test and ELISA, respectively. Late-convalescent-phase serum was also collected from 18 of these patients 3 to 24 months postinfection and assayed. The IgM ELISA values were strongly positive in sera collected during the first 2 months; at 3 to 9 months, they were negative or in the lower range of significance, and at 24 months all sera were negative. Paired sera from NE patients often fail to show seroconversion or a significant titer rise when tested by indirect immunofluorescence. Since all acute- and early-convalescent-phase sera were positive by IgM ELISA, this test could become an important tool for early diagnosis of acute human NE infections.
mesh_terms: D000208:Acute Disease; D000914:Antibodies, Viral / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D005455:Fluorescent Antibody Technique; D006476:Orthohantavirus / Q000276:immunology*; D006480:Hemorrhagic Fever with Renal Syndrome / Q000175:diagnosis* / Q000382:microbiology; D006801:Humans; D007075:Immunoglobulin M / Q000032:analysis*
chemical_list: D000914:Antibodies, Viral; D007075:Immunoglobulin M