1 Departments of Pediatrics, Medicine, and Medical Microbiology, University of Vermont College of Medicine, Burlington, Vermont
Twenty-two of 30 children residing in a children's center and 32 adult employees received a single inoculation of purified, killed, monovalent, influenza virus vaccine prepared with the Hong Kong variant of influenza A2 virus. All children showed significant four-fold or greater rises in HI antibody titer following vaccination, while 28 of 32 adults (88%) showed four-fold or greater rises in HI antibody titer. Twenty-five children living outside of the children's center were also immunized and those from whom paired sera were obtained (eight) showed four-fold or greater rises in HI antibody titer. Geometric mean titer rises from <10 to 93.6 in children and from < 10 to 70.9 in adults were recorded. Local reactions were limited to mild redness in one half of the children, and transient redness or soreness was seen in one half of the adults. No systemic reactions were seen in the children, but one adult had fever and malaise of 24 hours' duration.
In contrast to previously available influenza vaccines, the highly purified vaccine seems to be more satisfactory for use in children of school age; it should be particularly advantageous for use in children who are being immunized because of an underlying debilitating disease.
Submitted on September 9, 1969