Vaccine Prevents Most Cases of Chickenpox-Study

A vaccine prevents most cases of the chickenpox, and even when the vaccine fails, children tend to have a less severe case of the malady and are less likely to be contagious, researchers said on Tuesday.

A vaccine prevents most cases of the chickenpox, and even when the vaccine fails, children tend to have a less severe case of the malady and are less likely to be contagious, researchers said on Tuesday. Relatively few vaccinated children get varicella, commonly called chickenpox, according to the study published in the Journal of the American Medical Association. Before vaccinations became routine in the 1980s, there were about 4 million U.S. cases of chickenpox each year, causing roughly 100 deaths and 10,000 hospitalizations. At that time, at least 61 percent of children exposed to children with the chickenpox came down with the disease, which can be transmitted through the air. The study evaluated how often the illness, when it does occur, was transmitted to family members. If the ill children had not been vaccinated, 72 percent transmitted the virus to other family members. When the child with chickenpox had been vaccinated, the transmission rate was just 15 percent, the study said. “(The vaccine) was 100 percent effective in preventing severe disease, 92 to 100 percent effective in preventing moderate or severe disease, and 80 percent effective in preventing all forms of chickenpox,” said study author Dr. Jane Seward of the U.S. Centers for Disease Control and Prevention in Atlanta. The study examined 6,316 cases in a Los Angeles County community between 1997 and 2001.(Source: Reuters, August 2004)