Human influenza virus infection in mink: serological evidence of infection in summer and autumn.

During the period from July to November 1981, 42 out of 128 young mink of a flock were found to possess antibodies against the viruses A/Bangkok/1/79 (H3N2) and A/Kumamoto/37/79 (H1N1), which were currently prevailing human influenza viruses. Seroconversion against A/Bangkok/1/79 was found in 12 mink from August to November. HI antibody titers of greater than 1: 128 were found in 8 out of 42 mink at the first examination in July and August. These findings suggest that infection with these human influenza viruses was present in this flock during the period from birth (the beginning of May) to autumn, the non-prevalent season in man. Attempts at virus isolation were unsuccessful.