Comparative Trial of Influenza Vaccines

Abstract

Commercially prepared zonally and chromatographically purified bivalent (A/England-B/Mass) and monovalent (B/Hong Kong) inactivated influenza vaccines were given to 438 individuals 6-33 years old. The vaccines had been examined for antigen content by chick cell agglutination (CCA) tests and electron microscopic particle count determinations. Endotoxin and pyrogen content were determined by limulus amebocyte lysate (LAL) and rabbit pyrogenicity assays; and egg-associated protein contamination was estimated by total protein and single radial immunodiffusion assays. Although great differences (10-200-fold) were found in the amount of endotoxin or pyrogen in the vaccines, no significant differences were found in the febrile responses they induced. Both bivalent and monovalent vaccines induced fever of greater than or equal to 38 C at a rate of approximately 3 1/2-4% above background. The febrile responses were most frequent at 24 hours after inoculation and a higher rate was observed in children than adults. Local reactions consisting of tenderness, erythema or induration were seen in from 20-57% of the recipients and also were unrelated to the pyrogenic or host-derived materials in the vaccines. Adults had higher local reaction rates than children and some vaccines containing larger amounts of viral antigen induced significantly higher rates of reactivity than did vaccines containing smaller amounts of antigen. Although 37-51% of all recipients experienced either a local and/or febrile reaction to influenza immunization, the reactions were in general mild and would not consitute a significant disadvantage in the immunization of children over 6 years and adults to prevent influenza infection and its sequelae.

Inactivated Whole Virus Particle Influenza Vaccine Induces Anti-Neuraminidase Antibodies That May Contribute to Cross-Protection against Heterologous Virus Infection

“…Several factors may account for the low or negligible induction of anti-NA antibodies by SV. First, ether- and detergent-disrupted SVs are poor immunogens in mice and humans [ 31 , 32 ] because the viral RNA in the SVs, which affects APC activation, is degraded [ 13 ]. Second, the HA protein, which binds to sialic acid receptors, is preferentially endocytosed by APCs over NA or other viral proteins, subsequently inducing antibodies mainly against HA.…”

Influenza vaccination in the elderly

“…Local reactions were reported in from 20-57% of the recipients aged 6-33 y. 87 Clinical trials reported swelling up to 7.3% of vaccinated elderly aged 60 y and older. Local reactions are reported more frequently among the high-dose recipients (36% reported pain) than among standard-dose flu vaccine recipients (24% reported pain) in 65 y of age or older in US.…”

Safety and Impact on Training of the Influenza Vaccines in Elite Athletes Participating in the Rio 2016 Olympics

“…Generally, systemic symptoms, for example, fever, malaise, or myalgia, occur more often in individuals not vaccinated with TIV in the past and in younger subjects. 53 In this study, athletes of the N group were 3 years younger, whereas 21% of the N + S group was more often vaccinated against influenza in the past (both differences not statistically significant). The crucial conclusion is that a second flu vaccination during the same influenza season does not increase the frequency of adverse events, both local and general.…”