Infant immunisation with a pneumococcal conjugate vaccine: from the age of two months, for all infants

Abstract

(1) In France, before widespread infant immunisation with the 7-valent pneumococcal conjugate vaccine, there were about 13 deaths a year and about 145 cases of pneumococcal meningitis, often with serious sequelae. The peak incidence of pneumococcal meningitis occurs at approximately 5 months of age. (2) About 65% of the pneumococcal serotypes that cause meningitis in French children are covered by the 7-valent vaccine. (3) Several trials have yielded similar results: vaccination during infancy reduces the risk of invasive pneumococcal infection due to serotypes covered by the vaccine by 80% to 90%, leading to a relative reduction of 60% to 70% in the risk of invasive pneumococcal infections due to all serotypes. (4) In the United States, since the introduction of routine vaccination for all infants under 2 years of age, infant mortality due to invasive pneumococcal infections has fallen, with roughly one death prevented per 200 000 infants. Infant vaccination also appears to reduce the circulation of vaccine serotypes among unvaccinated subjects, especially those over 50 years of age. There is some evidence of replacement by non-vaccine serotypes, but the magnitude of occurrence is small. (5) The efficacy of the 7-valent pneumococcal conjugate vaccine in the prevention of acute otitis media in infants has been tested in several clinical trials: it is minimal to non-existent. (6) The adverse effects of the 7-valent pneumococcal conjugate vaccine are similar to those of other commonly used vaccines, and include fever, rash, urticaria, reactions at the injection site, and agitation. Serious allergic reactions have occurred: at least one spontaneous report of one serious allergic reaction per 500 000 vaccinated children. (7) There is consensus on the vaccination schedule: 3 intramuscular injections given at least 4 weeks apart, plus a booster at 12-15 months, if vaccination is started at 2 months of age. (8) In France, routine vaccination would prevent about a dozen deaths, several dozen cases of meningitis, and a few hundred hospital admissions per year, at a cost of at least one serious allergic reaction. (9) The risk-benefit balance is very favourable in infants who are at a high risk of invasive pneumococcal infection. It is also positive in other infants, and should therefore be routinely offered from the age of 2 months. Epidemiological monitoring must continue.