By Ben Harder

Hospitals are needlessly putting off vaccinating infants for hepatitis B, the Centers for Disease Control and Prevention reported this month. Until 1999, many hospitals vaccinated newborns against the virus, which infects up to 300,000 Americans each year and can cause serious liver damage and even cancer. But in 1999 the government recommended postponing the shots several months to keep newborns from being exposed to the mercury found in a vaccine preservative. All hepatitis B vaccines are now mercury free, but hospitals have been slow to resume early vaccination. The 1999 "recommendations had unexpected and lasting effects," says Anthony Fiore, a CDC physician. In Oklahoma, for example, newborns are about half as likely to be immunized as those born before the advisory.