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Officials of the Food and Drug Administration (FDA) recently approved the first vaccine to prevent serious pneumococcal disease, primarily bouts of meningitis and bacteremia, in young children. However, the vaccine, which protects against infections caused by seven strains of pneumococcus, also could provide a welcome side effect by helping to prevent ear infections, which are annoying and sometimes seriously threatening to children.

Without the vaccine, protecting young people against more serious pneumococcal infections has proved difficult. Such infections often strike infants, accounting for about 16,000 cases of pneumococcal bacteremia and 1,400 cases of pneumococcal meningitis annually throughout the United States. About 10% of children who develop meningitis die of the disease.

Meanwhile, the organism is responsible for about two-thirds of the nearly 8 million annual cases of ear infections that occur among young children in the U.S. each year, causing problems that, while not life-threatening, are painful to children as well as costly and disruptive to their parents. Frequent ear infections lead to countless trips to pediatricians, interrupted work schedules, and prolonged antibiotic treatments sometimes lasting up to two weeks. More importantly, such infections also can cause temporary hearing loss and thus may delay language development. Most children, however, outgrow their high susceptibility to ear infections by the age of 6.

Ear infections also account for about one-fourth of all prescriptions for antibiotics. The vaccine, if proved effective for this indication, thus might help the more general effort to reduce the indiscriminate use of antibiotics, a practice that is regarded as a major factor in the development of antibiotic resistance among bacteria. The strains that cause illnesses prevented by the new vaccine are also among the most resistant to the antibiotics traditionally used to treat these diseases.

``I think everybody is very eager to look at the ability of this vaccine to prevent more common but less lethal diseases, including ear infections,'' says Jesse Goodman, deputy director of the FDA's Center for Biologics Evaluation and Research. ``Biologically, it's reasonable to think it will have an impact.'' Thus, if the vaccine works against ear infections, ``it might be a very important tool'' in preventing many of them, he adds.

In a separate action, members of the Advisory Committee on Immunization Practices, which works closely with the Centers for Disease Control and Prevention, are recommending the vaccine's use in all infants up to age 23 months; in addition, they recommend its use in certain older children, ages 24 to 59 months, including African-Americans, Native Americans, and Alaskan Natives; in children with sickle cell anemia, HIV, and chronic diseases; and in those who are immunocompromised. The panel members also recommend that the vaccine be considered for other children ages 24 to 59 months, with priority given to those in group day care, children who are socially or economically disadvantaged, and children with frequent or recurring otitis media.

Wyeth Lederle Vaccines, a unit of Wyeth-Ayerst Laboratories, the pharmaceutical division of American Home Products Corp, will market the vaccine with the trade name Prevnar. The vaccine causes typical, mild side effects, such as redness at the site of inoculation and low-grade fevers. It is made by attaching characteristic cell-surface polysaccharides from the seven pneumococcal strains to a genetically modified nontoxic form of the diphtheria toxin protein CRM 197. Four doses of vaccine are recommended to develop full protection among recipients, given at 2, 4, 6, and 12 to 15 months of age. That dosing schedule will likely vary for older children at the discretion of individual pediatricians. Its cost to physicians will be $58 per dose.

``We are pleased with the committee's recommendation because it ensures that the vaccine will be expeditiously provided to children who are most vulnerable to invasive pneumococcal disease,'' says Peter Paradiso, vice president of scientific affairs and research strategy for Wyeth Lederle. Because clinical studies indicate it can prevent ear infections, company officials intend to seek FDA approval for this additional use, he notes. For instance, vaccinated children participating in a study under way in Finland develop 60% fewer ear infections compared to those in a control group, according to Paradiso.

Another large multicenter study of the vaccine was directed from the Northern California Kaiser Permanente in Oakland. It enrolled 38,000 children, about half of whom received the vaccine, which proved 100% effective against the seven strains and 90% effective against illnesses caused by all pneumococcal subtypes. Among those children who were vaccinated, there was a 9% decrease in pediatric visits for ear infections resulting from all causes and a 20% reduction in the need for ear tubes among children suffering from frequent ear infections. The surgical insertion of tubes that drain infection-prone fluid from this anatomic site is often recommended for persistent sufferers of middle ear infections.

Marlene Cimons