[Serologic examination of patients with hemorrhagic fever with renal syndrome in the European part of the USSR].

Certain features of humoral immunity in patients suffering from hemorrhagic fever with renal syndrome (HFRS) in the territory of the European USSR were established: a trend for increasing antibody levels for a long time after convalescence (approximately 6 months) and the lack of significant decline of antibody levels for many years (5-10). Comparative clinico-serological studies revealed the occurrence of subclinical and atypical forms of HFRS disease.