Time to vaccinate everyone under 30?

2002 JUN 5 - (NewsRx.com & NewsRx.net) -- A massive immunization campaign to vaccinate young Americans against smallpox now might save many more lives than a strategy focused on isolating and vaccinating those at risk only after a terrorist attack. But a mass-vaccination approach would cost more up front and would have to be done carefully because of potential harm from the vaccine itself.

Those conclusions, from two computerized analyses made by pediatric researchers at the University of Michigan Health System, were presented in Baltimore, Maryland at the annual conference of the Pediatric Academic Societies, the largest pediatric research meeting in the country.

One study looked at the cost-effectiveness of different vaccination strategies. It found that a campaign to immunize everyone younger than 30, before any potential terrorist smallpox attack, could save hundreds more lives and years of economic productivity in the event of an attack than the quarantine-and-vaccinate approach that the federal government currently prefers.

But the other study, on the potential risks of a mass vaccination campaign to members of the same age group, found that reactions to the vaccine could kill dozens and sicken thousands. So, any vaccine campaign would have to exclude those most likely to react badly to the shot.

The researchers - led by U-M pediatricians Matthew Davis, MD, MAPP, and Alex Kemper, MD, MPH, MS, - hope their results may help guide public officials at a time when the potential for a smallpox outbreak looms large for the first time in decades. Their research group, the Child Health Evaluation and Research Unit of the U-M Medical School, holds a contract with the Centers for Disease Control and Prevention to study vaccination issues.

Even though smallpox was wiped out in 1977 through mass vaccination, fears persist that terrorists or rogue governments may harbor smallpox cultures stolen from the former Soviet Union. Last fall's deadly anthrax outbreak renewed fears of a smallpox attack, and led the U.S. government to beef up its stockpile of smallpox vaccine and revisit response strategies.

Many Americans have little or no immunity against smallpox, because routine inoculation of infants and children was stopped in 1972 when the risk of vaccine side effects was judged to outweigh the benefit. Many people vaccinated earlier have probably lost much of their immunity.