Prevalence of Antibodies to Type A Influenza Viruses in Swine Sera 1990-1994

Abstract

A total of 3, 120 swine sera collected for the years 1990-94 were tested for the presence of hemagglutination-inhibition (HI) antibodies against swine (H1N1) and human (H1N1 and H3N2) strains of influenza virus. No HI antibody against the swine strains was recognized during 18 months, though a slight prevalence (1.5-9.2%) of the antibodies was observed over the entire period. A wide variance in the incidence (0-26.3%) of antibodies against the human H3N2 strains was observed among the swine population.