An experimental combination childhood vaccine created to protect against both pneumonia and meningitis provided less protection than separate vaccines for the diseases, a new British study finds.The combination vaccine was in the early stage of development, and was designed to protect against one form of pneumococcal infection and one form of meningitis. But the study found that children given the combined vaccine developed less of an immune response to meningitis than the standard separate vaccine.The study included 240 healthy infants aged 7 to 11 weeks old when the trial began. Half were given the experimental vaccine three times -- at 2, 3 and 4 months of age, while half received the two separate vaccines now in common use on the same schedule. All the children also received the routine shots recommended for their age group.Tests of their immune system response one month after the last shots were given found less protection against meningitis in the children who got the combination vaccine. Those children also had a reduced response to two of the other vaccines they were given.The findings appear in the April 13 issue of the Journal of the American Medical Association.
