SEROLOGICAL STUDIES ON INFLUENZA DURING A NINE-MONTH PERIOD 1

Abstract
The results reported in this paper were obtained from expts. designed to a) ascertain the approach of a respiratory epidemic, b) determine the nature of the epidemic, c) determine the duration of antibody levels resulting from vaccination, and d) determine the antibody titers in a group of presumably normal individuals. Sera were derived from 2 sources, a) 52 medical students were bled monthly from Oct., 1945, to June, 1946, inclusive, and b) 25 pairs of acute and convalescent phase sera obtained during the epidemic. AU sera were handled in an identical manner; sera from one individual were handled simultaneously. The serological tests employed were cold agglutinations, Streptococcus MG #9 agglutination, agglutination-inhibition (Hirst), and complement-fixation tests for members of the psittacosis-lympho-granuloma venereum group (Lygranum CF). The results show that the epidemic was due to influenza B, and the virus was present several months prior to the actual outbreak. There were a few cases of atypical pneumonia, but no case of infection with a member of the psittacosis -lymphogranuloma venereum group. Antibody levels remained constant for at least 5 months in most cases following vaccination. The approach of the influenza epidemic could not be detd. in the student group, as high titers were present in the October sera. These tests may be used as a group to determine the etiology of a respiratory epidemic by diagnostic laboratories.