DO HEALTHY CHILDREN NEED TO GET VACCINATED?

Rationale for childhood vaccination Annual influenza vaccine is widely recommended for children at high risk of serious or complicated influenza infection All children are at substantially increased risk for influenza-related hospitalisations In some countries healthy children aged 6–23 months are encouraged to receive influenza vaccine As well as reducing the risk to their own health, it reduces influenza infection in their contacts May also reduce influenza infections in adults by interfering with the circulation of the virus in the community

Assessment of vaccine efficacy in healthy children Jefferson T et al. Lancet 2005; 365: 773–80. Age 2 years or younger (0 studies) Age 6 years or younger (3 studies)0·16 (0·06–0·42) Older than 6 years (1 study)0·47 (0·23–0·97) Total 0·21 (0·08–0·52) Live attenuated vaccines Relative risk (random) 95% CI Age 6 years or younger (2 studies)0·42 (0·14–1·20) Older than 6 years (4 studies)0·28 (0·20–0·40) Total0·35 (0·24–0·53) Inactivated vaccines Age 2 years or younger (2 studies)0·76 (0·12–4·71) OVERALL EFFICACY = 79% OVERALL EFFICACY = 65%

Assessment of vaccine efficacy in healthy children Influenza vaccine versus placeboEffect size (95% CI) Lower respiratory tract disease0.18 (0.02–1.35) Otitis media (OM)0.78 (0.40–1.54) Admission owing to acute OM1.41 (0.62–3.24) School absenteeism0.49 (0.26–0.92) Secondary cases1.68 (0.56–4.99) Influenza vaccine versus no intervention OM0.13 (0.01–2.59) School absenteeism (> 4 days)0.14 (0.07–0.27) Jefferson T et al. Lancet 2005; 365: 773–80.

Influenza vaccination of children at day care prevents illness in their contacts Illness in unvaccinated contacts (%) All respiratory illness Febrile respiratory illness Contacts of unvaccinated children Contacts of vaccinated children Unvaccinated household contacts of vaccinated day care children had 42% less febrile respiratory illnesses than the contacts of unvaccinated day care children Hurwitz ES et al. JAMA 2000; 284: 1677–82.

Influenza vaccination of children at day care prevents illness in their contacts and reduces impact on family Number Missed school Adult missed work Physician visits Earache Antibiotics Over-the-counter (OTC) medications Contacts of unvaccinated children Contacts of vaccinated children Hurwitz ES et al. JAMA 2000; 284: 1677–82.

By courtesy of APACI Asia-Pacific Advisory Committee on influenza