Influenza vaccine: the effects of the 1986/1987 viral strains

Abstract

One hundred and twenty healthy volunteers were recruited for a study to evaluate the reactogenicity and serological response of differing doses of the 1986/87 World Health Organization-recommended influenza viral strains. Each vaccine was prepared by Institut Merieux and contained A/Mississippi/1/85, A/Chile/1/83 and B/Ann Arbor/1/86. One vaccine was formulated as a 10/10/10 micrograms HA and the other as a 15/10/15 micrograms HA. No significant advantage could be found with the 15/10/15 micrograms HA combination and it was recommended, therefore, that a 10/10/10 micrograms HA formulation was to be preferred. This vaccine demonstrated a minimal cross-sensitivity to the A/Singapore/6/86 influenza strain. In view of the prevalence of the A/Singapore strain, a second study was subsequently undertaken with a monovalent A/Singapore/6/86-like vaccine in a further 62 volunteers. This demonstrated an overall sero-conversion rate of 90%. Local side-effects with both vaccines were lower than in a similar study in 1984 and this may reflect a reduction in endotoxin levels achieved by a minor modification in the manufacturing technique. These studies confirmed the efficacy of a trivalent A/Mississippi, A/Chile, B/Ann Arbor influenza vaccine and the efficacy of, and necessity for, an additional A/Singapore vaccine.

Influenza vaccination in a boarding school population

“…No significant difference could be found between the split and subunit vaccines, each giving very similar responses. There was no improvement achieved by giving the second dose of vaccine in children of this age group although the overall response was lower than in a similar study performed in adults 6 .…”