Vaccine Prevented Surprising Number of Pneumonia Deaths

New York Times Syndicate
By Jeff Nesmith

March 25, 2005

WASHINGTON -- Vaccinations against a pneumonia-causing bacteria reduced deaths among a group of African children by a surprisingly large 16 percent, researchers said Friday.

The experimental program was described by Dr. Cynthia Whitney of the Centers for Disease Control and Prevention as "having major implications for how we can prevent deaths in children worldwide."

The vaccinations reduced the incidence of pneumococcal pneumonia by 77 percent among about 8,000 children in Gambia, a tiny, rural west African country, when compared to a similar group who were not vaccinated.

But the experiment, described in an article being published Saturday in the British medical journal The Lancet, surprised researchers because of the vigorous way it prevented deaths.

They said the fact that deaths among vaccinated children were 16 percent lower than those given a placebo indicated that the burden that pneumococcal bacteria imposes on children in developing countries is much heavier than they had believed.

Diseases caused by pneumococcal bacteria kill an estimated 800,000 to 1 million children a year, 90 percent in developing countries, according to the World Health Organization. In addition to pneumonia, it causes meningitis and blood infections.

Whitney, acting chief of the CDC respiratory diseases branch, said the trial, which was conducted between 2000 and 2004 in Gambia produced "stellar results."

Gambia snakes along the banks of the Gambia River in West Africa for about 400 miles. It is only about 20 miles wide.

Children received the vaccine in its far eastern reaches, an area health experts describe as among the most remote in Africa.

Dr. Nathaniel Pierce, professor of international health at Johns Hopkins University and one of the researchers, said that 17,000 children received injections of either vaccine or an ineffective placebo.

The vaccine was designed to increase immunity against nine types of pneumococcal disease prevalent in Africa.

After 30 months, Pierce said, examinations of hospital records showed that vaccinated children had 77 percent fewer cases of pneumococcal disease.

But the fact that the vaccinated group had 16 percent fewer deaths from all causes in an area where malaria is prevalent indicates the role of the pneumonia bacteria in childhood mortality is much higher than previously believed, he said.

The next step, Pierce said, will be to provide vaccine to all children who were in the "control" group and received only the placebo.

But the next hurdle, said Dr. Orin Levine of the Global Alliance of Vaccines and Immunizations, will be to get the vaccine in use in developing countries.

That has taken up to 20 years with vaccines in the past, he said. The organization, which recently received a $750 million grant from the Bill and Melinda Gates Foundation, will push for widespread use of the vaccine within the next three years, he said.

In addition to CDC and the Johns Hopkins school of public health, sponsors of the Gambia experiment included the National Institute for Allergy and Infectious Diseases and the U.S. Agency for International Development.

Vaccine used in the trial was donated by its manufacturer, Wyeth Pharmaceuticals of Collegeville, Pa.

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