The follow-up study of swine and Hong Kong influenza virus infection among Japanese hogs.

Abstract
ARIKAWA, J., YAMANE, N., TOTSUKAWA, K. and ISHIDA, N. The Follow- Up Study of Swine and Hong Kong Influenza Virus Infection among Japanese Hogs. Tohoku J. exp. Med., 1982, 136 (4), 353-358 - Pigs in Miyagi Prefecture, Japan were examined for swine (Hsw1N1) and Hong Kong (H3N2) influenza virus infection by serological tests. The results obtained revealed that a swine influenza virus was prevalent with relatively high positive ratios throughout that time, and that the Hong Kong influenza virus closely related to a recent human epidemic strain, A/Yamanashi/2/77, also persisted, corresponding to a human endemic. These epidemiological findings strongly suggested the possibility of direct transmission of Hong Kong virus from humans to pigs and vice versa.