Asian influenza in a Royal Air Force Boy Entrants School

Summary Two outbreaks of asian influenza in the same R.A.F. boys' school are described. The major outbreak, in September, 1957, amounted to 899 cases in a population of 1827 over a period of 19 days. The minor outbreak in October and November, 1957, consisted of 110 cases and occurred mainly among 392 new boys who entered the school in October. The differing epidemiological characteristics of the two outbreaks are described, and an account is given of the illness, which was similar in each outbreak except for some variation in the frequency of certain signs. The major outbreak posed serious administrative problems and some aspects of the plans required to meet these are described. The epidemiological characteristics and possible reasons for the differences between them are discussed. It is concluded that the probable cause was dissimilar immunity states in the populations at risk due to the altered secular relationship with the influenza epidemic in the country as a whole. Our thanks are due to Dr. J. C. MacDonald, of the Epidemiological Research Laboratory P.H.L.S., and to Flight Lieutenant W. W. Holland for their advice on the preparation of this paper and to the director general of medical services for permission to publish.