Smallpox Vaccination Program Safe
Few Side Effects Reported in Large-Scale Military Vaccination Program
June 25, 2003 -- Large-scale smallpox vaccination programs can be carried out safely, according to new research from the U.S. military.
Although concerns regarding potentially dangerous complications caused by the smallpox vaccine have emerged in recent months, researchers say the military's smallpox vaccination program had lower than expected rates of serious side effects.
A nationwide smallpox vaccination program began in December 2002 for key military and State Department personnel and emergency health-care workers. In March, the CDC announced that people with heart disease would no longer be eligible for smallpox vaccination after several reports of heart problems and at least one death were linked to the smallpox vaccine.
In a study published in The Journal of the American Medical Association, researchers say the Department of Defense vaccinated more than 450,000 military personnel from Dec. 13, 2002 until May 28, 2003 at a variety of locations. Vaccination was required for all troops except pregnant women or those with skin conditions or immune disorders that are not recommended for vaccination due to a risk of complications.
Researchers found that between .5% and 3% of people who received the vaccine needed short-term sick leave for vaccine-related illness, such as fever, usually eight to 12 days after vaccination. Most required only one day of sick leave.
"Our experience suggests that broad smallpox vaccination programs may be implemented with fewer serious adverse events than previously believed," write the researcher John Grabenstein, R.Ph, PhD, of the U.S. Army Military Vaccine Academy in Falls Church, Va., and colleagues.
Overall, rates of adverse events were generally lower than those found during past vaccination efforts. Once case of encephalitis (inflammation of the brain) and 37 cases of inflammation of the heart occurred, but all cases recovered.
Another study published in the same journal examined the first cases of inflammation of the heart that occurred during the military smallpox vaccination program. Although only four cases of this condition had been reported from 1955 to 1986, defense department researchers say it should be considered an "expected but apparently uncommon adverse event associated with smallpox vaccination."