Full vaccination provide substantial flu protection in children
Flu vaccination continues to be highly recommended for high-risk paediatric populations, with a recent study showing substantial protection among children who received the vaccine and especially in those who were fully vaccinated.
In the study population of 9,547 children (aged 6 to 59 months) hospitalized during the 2010/11 to 2013/14 influenza seasons, corresponding to 9,982 hospitalization events, 12.8 percent (n=1,280) were diagnosed with influenza; the rates of disease positivity fluctuated between 11.5 to 14.5 percent across seasons. At least one vaccination was reported in 11.5 percent (n=1,151) of the children.
The overall vaccine effectiveness (VE) against laboratory-confirmed influenza hospitalization was calculated to be 60.4 percent for children who received full vaccination. The corresponding value for those who were only partially vaccinated was 39.2 percent.
In three of the four seasons examined, full vaccination yielded statistically significant flu protection while partial vaccination was only significantly protective in two seasons. Any vaccination had significantly higher VE in children aged 25 to 59 months than in those aged 6 to 23 months (64.4 vs 35.6 percent; p=0.012).
Compared with partially vaccinated children, those who received full vaccination had nominally higher VE in subgroups with influenza A (60.7 vs 50.6 percent) and A/H1N1 (82.1 vs 31.5 percent), and significantly higher VE in the influenza B subgroups (58.0 vs 11.8 percent; p=0.03).
VE values were consistently nominally higher in fully than in partially vaccinated children, regardless of season, influenza type, age group, sex, complex chronic condition and presence of asthma.