| Abstract: | Two influenza epidemics in Britain in 1968-9 and 1969-70, were due to the Hong Kong/68 variant of influenza A2 virus. The first epidemic was prolonged with low morbidity and mortality rates; the second was sharp with high rates. The difference between total morbidity and mortality in the two epidemics, however, was less than it appeared to be—the estimated excess morbidity and mortality due to all causes in 1969-70 was only about 50% greater than in 1968-9.Antibody studies showed that about one-quarter of two groups of adults investigated were infected in the first epidemic and about one-third in the second. After the two epidemics about one-third still had no antibody to the A2/Hong Kong/68 virus. |
