Incidence and recall of influenza in a cohort of Glasgow healthcare workers during the 1993-4 epidemic: results of serum testing and questionnaire

Abstract

The study population consisted of all 970 healthcare workers at four acute hospitals in Glasgow who had serum stored for a routine post-vaccination test for antibody to hepatitis B between 1 February and 26 October 1993. This group was likely to be representative of healthcare workers in contact with patients as internal audits have shown that over 80% of targeted staff complete the hepatitis B vaccination programme. After the influenza epidemic (late October 1993 to end of January 1994) we invited these healthcare workers to provide a further blood sample and complete a questionnaire on their history of influenza and respiratory infection between the end of October 1993 and 1 February 1994. In all, 163 subjects were excluded as they had resigned or were on long term sick leave or maternity leave. Of the remaining 807 subjects, 602 (75%) agreed to enter the study and provided the blood sample during six weeks beginning 1 February 1994.