A vaccine against pneumonia and invasive pneumococcal disease, a severe form of bacterial infection, can substantially reduce hospital admissions and improve the survival of children in developing countries, concludes a trial published in this week’s issue of The Lancet.
The authors believe the vaccine should be made available to children in Africa, where rates of severe invasive pneumococcal disease are up to ten times higher than in industrialised countries.
Pneumonia causes an estimated 19% of the 10 million childhood deaths worldwide annually. The bacterium Streptococcus pneumoniae is responsible for up to half of all cases of severe childhood pneumonia in developing countries. It also causes serious bloodstream infections, meningitis, and otitis media (inflammation of the middle ear).
Felicity Cutts (Medical Research Council, UK and WHO) and colleagues recruited children aged 6–51 weeks in The Gambia from August 2000 to February 2003. Children were randomly assigned to receive either, three doses of diphtheria-tetanus-pertussis—Haemophilus influenzae serotype b vaccine as a control (8719), or three doses of this tetravalent vaccine mixed with a nine-valent pneumococcal conjugate vaccine (8718), with intervals of at least 25 days between doses. 333 of the 8189 children given the pneumococcal vaccine had an episode of pneumonia confirmed by chest x-ray compared with 513 of 8151 in the control group. The vaccine reduced the first episode of pneumonia diagnosed by chest x-ray by 37% and reduced admissions to hospital by 15%. Disease caused by the types of pneumococcus bacteria in the vaccine was lowered by 77% and overall child mortality by 16%. The vaccine also had a good safety profile.