Researchers in Finland studied the effectiveness of trivalent inactivated influenza vaccine against laboratory-confirmed influenza A and influenza B infections in children aged 9 months to 3 years.
631 children were part of this study. These children were given 0.5ml of the vaccine. They were examined every time they had fever or showed any signs of respiratory infections. Pathological tests like viral culture, antigen detection, and RT-PCR assays of nasal swab specimens were examined to confirm the influenza diagnosis. The primary effectiveness of influenza vaccination was calculated by comparing the proportion of infections in vaccinated children and unvaccinated children. Out of the 154 vaccinated children, 7 children contracted influenza during the early phase of the study, while 61 of 456 unvaccinated children contracted the influenza infection. The study suggested that the trivalent inactivated influenza vaccine was effective in preventing influenza among young children
. Therefore the findings suggest many countries should reassess the influenza vaccine recommendations. Source:
The Lancet Infectious Diseases