Newborn Hepatitis B Vaccinations Fell in 2000
Brief Halt in Vaccination Program in 1999 Led to Drop, CDC Says
May 18, 2004 -- The vaccination of newborns against the hepatitis B virus dropped sharply after a brief suspension of the practice, and it is not yet clear if rates have returned to their pre-suspension levels, the CDC reports.
Newborn vaccinations were suspended late in the summer of 1999 due to concerns about exposure to mercury contained in the vaccine preservative thimerosal. The suspension was lifted two months later when thimerosal-free hepatitis B vaccine became widely available, but immunization rates of newborns were slow to rebound, the report noted.
In the year before the suspension, 47% of newborns received their first dose of the hepatitis B vaccine within 12 hours of birth, but roughly a year after the suspension just 33% were vaccinated during their first day of life.
Immunization guidelines call for children to receive three doses of hepatitis B vaccine by the age of 19 months, with the first dose to be given to newborns. A new CDC report includes an analysis of the vaccination status of more than 41,500 children born before, during, and after the birth-dose suspension. It shows that 750,000 fewer newborns were vaccinated in 2000 than in 1998.
The reduction in newborn immunizations led to some 182,000 children being undervaccinated for hepatitis B at 19 months of age in 2000, compared with 1998 coverage levels, says Elizabeth Luman, MS, of the CDC's National Immunization Program. The CDC report is published in the May 19 issue of TheJournal of the American Medical Association.
The rate at which children received the complete course of hepatitis B vaccinations also dropped following the suspension but rebounded quickly. This suggests that most children did get vaccinated, but experts say the decline in newborn vaccinations is still troubling because infections acquired early in life are so dangerous.
Why It Matters
The CDC estimates that 20,000 women with hepatitis B give birth each year in the U.S., and between 900 and 1,110 of their children are infected at birth. Mother-to-newborn transmission of the virus is especially serious, with 90% of those infected at birth developing chronic hepatitis B infection and a quarter of these infections resulting in death from liver disease during adulthood.
Infants who are not infected at birth but who go home to households with people infected with hepatitis B are also at risk. Although sexual transmission and blood-to-blood contact are the most common means of hepatitis B infection, the virus can also be spread through contact with saliva.
"We know that roughly 30% of kids who live in households with people who are infected will also become infected within the first five years of life," University of Wisconsin pediatrics professor Thomas Saari, MD, tells WebMD. "This virus is very durable. It can live on a countertop or table for up to a week."