Children from childcare centres were recruited to study the effect of flu vaccine. One group was unvaccinated, one group partially vaccinated and one group fully vaccinated. Influenza-like illnesses 105 children had influenza-like viruses out of 381 children. Swabs were taken from 117 and 175 influenza like viruses found. 44% of swabs held multiple viruses. Vaccinated children were up to 6 times more likely to be infected.
First published: 31 January 2014