October 1973

Protection With Split and Whole Virus Vaccines Against Influenza

Author Affiliations

DeKalb, Ill; Chicago

From the Department of Medicine, University Hospital, Abraham Lincoln School of Medicine (Drs. Akers, Stanley, and Jackson), and the University Health Service, Northern Illinois University, DeKalb. Dr. Ruben is now with Montefiore Hospital, Pittsburgh.

Arch Intern Med. 1973;132(4):568-571. doi:10.1001/archinte.1973.03650100082015

In a trial of influenza virus vaccines, 3,103 students (13.6% of a campus population) were given a standard dose of vaccine (400 chick-cell agglutination [CCA] units of influenza A and 300 CCA units of influenza B) in October or December 1971. Fifty-eight percent of the vaccinees received a tri-(n-butyl) phosphate (TNBP) split virus vaccine; 42% received inactivated whole virus vaccine. In January, a discrete influenza outbreak occurred. Influenza A/HK virus (H3N2) was recovered as the predominant infecting agent. In a three-week period, 168 students sought medical assistance for febrile influenza. Only eight (4.8%) of these were vaccinees, representing a 69% reduction from the attack rate in nonvaccinees. The protection derived from split virus and whole virus vaccine was similar.