The vaccine, which will be considered soon for approval in the United States, is intended to protect youngsters from a variety of illnesses caused by the pneumococcus bacteria.
The vaccine has already been shown to lower the risk of earaches, meningitis and blood poisoning resulting from the germ, according to research released Tuesday from a major study.
"It's a triumph for kids," said Dr. Steven Black, who presented the data at an infectious-disease meeting sponsored by the American Society for Microbiology.
Around the world, pneumonia caused by pneumococcus results in an estimated 600,000 deaths annually. Black estimated that the vaccine could prevent 450,000 of them.
In the United States, the bacteria is rarely fatal. However, it does account for 100 to 150 deaths each year.
An adult vaccine for the germ has long been available, but it does not work in youngsters. The new vaccine was developed by Wyeth-Ayerst Laboratories, which paid for the testing. An advisory committee of the Food and Drug Administration is scheduled to meet Nov. 4 to consider whether to recommend its approval.
Black and colleagues from the Kaiser Permanente health plan tested the vaccine on 37,830 children in California. Half of them got the shots at two, four and six months, and again between 12 and 15 months. The rest got a different experimental vaccine that has no effect on pneumococcus.
During three years of follow-up, 1,309 of the children were diagnosed with pneumonia. The vaccinated youngsters were one-third less likely to get moderately severe pneumonia that was bad enough to show up on X-rays, and they were 75 percent less likely to get severe cases, which occurred in 33 children.
Earlier data released from the study showed that vaccinated youngsters were 89 percent less likely to get bacterial blood poisoning or meningitis. And they were about 20 percent less likely to have inner ear infections bad enough to require insertion of drain tubes.
"It's a remarkable vaccine that will have a dramatic effect," said Dr. Henry Shinefield, another of the Kaiser researchers.
About 90 types of the bacteria cause illness. The new vaccine is designed to guard against seven varieties that are most common in children. These are also types of the bug that are frequently resistant to common antibiotics.
Dr. Cynthia Whitney of the U.S. Centers for Disease Control and Prevention noted that about one-quarter of victims of severe pneumococcus infections in the United States have bacteria that are resistant to penicillin, and nearly 15 percent are impervious to at least three drugs.
She noted that the new vaccine makes youngsters less likely to carry and spread the bacteria. This cold reduce the spread of the bacteria even to adults who are not vaccinated.
Written By Daniel Q. Haney