Vaccine helps prevent children from becoming carriers of associated pneumococcal bacteria

April 30, 2001

Two separate studies conducted by the Johns Hopkins School of Public Health concluded that the new conjugated pneumococcal vaccine, which is sold under the brand name Prevnar, effectively protects Native American children from seven types of Streptococcus pneumoniae bacteria and helps protect vaccinated children from becoming carriers of those types. Pneumococcal infections can cause a number of serious illnesses including deadly bacterial meningitis.

The studies are the first to examine the vaccine's effectiveness in a high-risk community and the first to show that Prevnar-vaccinated children are less likely to carry the targeted types of pneumococcal bacteria. The findings of both studies were presented at the Pediatric Academic Societies Conference in Baltimore, Maryland.

"Navajo and Apache Indian children are five times more likely to have serious pneumococcal infections compared to other children in the United States. Some vaccines do not work as well among Native American people, but our studies indicate that this new pneumococcal vaccine is extremely effective and should help prevent infections," says Katherine O'Brien, M.D., who is lead author of both studies and a research professor with the Center for American Indian Health at the Johns Hopkins School of Public Health.

For the first study, researchers selected more than 8,000 infants and toddlers living in 38 Navajo and White Mountain Apache Indian communities between 1997 and 1999. All of the children were between six weeks and two years of age. Each of the 38 communities was randomly assigned to receive either the pneumococcal vaccine or a control vaccine.

"We found that the vaccine was nearly 83 percent effective at preventing serious pneumococcal infections among infants who received at least one dose of the vaccine prior to seven months of age. The vaccine was 86 percent efficacious among all infants who received at least one dose of the vaccine prior to two years of age. These results may also be good news for other groups who are also at increased risk for pneumococcal disease, such as children in daycare and African-American children," explains Dr. O'Brien.

For the second study, researchers randomly selected 577 children from the first study and examined their noses for the presence of pneumococcal bacteria. The pneumococcal vaccine did not impact the proportion of children carrying pneumococcal bacteria of any type. Overall pneumococcal bacteria were found in the noses of 62 percent of the children vaccinated with the pneumococcal vaccine and in 64 percent of the children vaccinated with the control vaccine.

However, according to the research, children who received the pneumococcal vaccine were less likely to carry the seven types of pneumococcal bacteria targeted by the vaccine compared to children who received the control vaccine.

"The finding is significant, because it shows the vaccine protects children from becoming carriers of the targeted bacteria. This could help reduce the spread of the bacteria to children and adults in the community who have not been vaccinated," explains Dr. O'Brien.
L. Moulton, R. Reid, G. Kumar, J. Oski, L. Brown, R. Weatherholtz, M. Santosham, J. Hackell, R. Kohberger, I. Chang, and G. Siber contributed to the work of the first study. M.A. Bronsdon, G.M. Carlone, R.R. Facklam, B. Schwartz, R.R. Reid, M. Santosham contributed to the work of the second study.

Wyeth Lederle Vaccines, the National Institutes of Health, USAID, and the Centers for Disease Control and Prevention provided funding for the studies.

Johns Hopkins University Bloomberg School of Public Health

Related Bacteria Articles from Brightsurf:

Siblings can also differ from one another in bacteria
A research team from the University of Tübingen and the German Center for Infection Research (DZIF) is investigating how pathogens influence the immune response of their host with genetic variation.

How bacteria fertilize soya
Soya and clover have their very own fertiliser factories in their roots, where bacteria manufacture ammonium, which is crucial for plant growth.

Bacteria might help other bacteria to tolerate antibiotics better
A new paper by the Dynamical Systems Biology lab at UPF shows that the response by bacteria to antibiotics may depend on other species of bacteria they live with, in such a way that some bacteria may make others more tolerant to antibiotics.

Two-faced bacteria
The gut microbiome, which is a collection of numerous beneficial bacteria species, is key to our overall well-being and good health.

Microcensus in bacteria
Bacillus subtilis can determine proportions of different groups within a mixed population.

Right beneath the skin we all have the same bacteria
In the dermis skin layer, the same bacteria are found across age and gender.

Bacteria must be 'stressed out' to divide
Bacterial cell division is controlled by both enzymatic activity and mechanical forces, which work together to control its timing and location, a new study from EPFL finds.

How bees live with bacteria
More than 90 percent of all bee species are not organized in colonies, but fight their way through life alone.

The bacteria building your baby
Australian researchers have laid to rest a longstanding controversy: is the womb sterile?

Hopping bacteria
Scientists have long known that key models of bacterial movement in real-world conditions are flawed.

Read More: Bacteria News and Bacteria Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to