Serological Investigation of University Students

DURING the 1957 influenza epidemic in Northern Ireland we were able to confirm the clinical diagnosis of influenza in the majority of patients from whom specimens were received. There remained, however, a number of patients with a clinical diagnosis of influenza from whom we could neither recover virus nor demonstrate a rise of antibody in the convalescent specimen of paired sera. We decided, therefore, to try to discover what proportion of inidividuals, xvho had had attacks regarded as influenza, hadl serological evidence of infectioniwithl the Far East influenza virus/1957. The fact that the Far East/1957 virus strains showed no cross-reactions in the hemnagglutination inhibition (H.I.) test with other strains of Influenza A virus (Jensen, 1957; Meyer, Hillenanii, Miesse, Crawford and Bankhead, 1957) made this a relatively simple problem. \ group of university students consistinig of sixty-two fourth-year medical stuclenits and twenty-one resi(lents of a womiien students' lhostel were investigated. Blood samples were obtainiedl fromii eaclh of the studenits. TI'he medical students were asked to provide a written account of thleirillnesses during the previous month and the histories of the resi(letnts of the women's lhostel were recordedl.