"The booster can be given if [it has been] at least four weeks after the first dose," said Gershon, who is also president-elect of the Infectious Diseases Society of America. Or, it can be given years later, if necessary, she said.
According to the CDC, all children aged 12 months through 12 years old should have two doses of the vaccine. The first dose can be given at 12 to 15 months of age, and the second at 4 to 6 years. Older children, 13 and up, who haven't had the disease in childhood, can be given two doses four to eight weeks apart.
Some adults should consider the vaccine. Ask your health-care provider if you fall into that recommended group, which includes people who have never had the disease.
No vaccine is perfect, experts said.
In 2006, a combination vaccine that included not only chickenpox but measles, mumps, and rubella was licensed, cutting down on the number of shots needed. But that combination vaccine is not currently available in the United States, said Nalini Saligram, a spokeswoman for Merck & Co., which makes it. But it is expected to be back in supply by 2009.
To learn more about chickenpox vaccine, visit the American Academy of Family Physicians.
SOURCES: Anne Gershon, M.D., professor of pediatrics, Columbia University College of Physicians and Surgeons, New York City, and president-elect, Infectious Diseases Society of America; Robert Frenck Jr., M.D., professor of pediatrics in infectious diseases, Cincinnati Children's Hospital, Ohio, and member, American Academy of Pediatrics Committee for Infectious Diseases; Nalini Saligram, spokeswoman, Merck & Co., Whitehouse Station, N.J.
All rights reserved