Vaccination update. Hib, hepatitis, polio, varicella, influenza, pneumococcal and meningococcal disease.

Immunization of infants and children is the most effective strategy for decreasing the incidence of some infectious diseases. Most invasive disease due to Haemophilus influenzae type b occurs before age 5 years, and routine vaccination of infants for hepatitis B is currently recommended because selective immunization of high-risk persons has not been feasible. Decades of use of poliovirus vaccine has effectively eliminated cases of wild-virus infection, although some vaccine-related cases still occur. The newly approved varicella vaccine appears to be a cost-effective way to decrease infection rates in children. Improved immunization rates for influenza and pneumococcal and meningococcal diseases could help decrease excess mortality in elderly persons and those with chronic illness.