U.S. hepatitis A vaccine rates vary widely, survey shows

Although about 85 percent of kids in two U.S. states have had a complete set of hepatitis A vaccines, overall just three in 10 have had both shots, according to a new survey from the Centers for Disease Control and Prevention (CDC).

In certain states, particularly those in the south, midwest and eastern U.S., those rates are lower - with about three kids out of 10 getting one shot and about two out of every 10 kids getting the full immunization.

"One reason for lower rates of hepatitis A vaccination in some states is because of the recommendation history," said Dr. Christina Dorell, the lead author of the study in the journal Pediatrics and a researcher at the CDC.

In 1999, the CDC's Advisory Committee on Immunization Practices recommended the vaccine for children in 11 states in the western United States where infection rates were the highest. In six other states, the Committee said that the vaccine could be "considered" for children.

In 33 states, recommendations for routine vaccination came on board in 2006, but only for one-year-olds. For teenagers, the guidance is less strong, again saying that the vaccine can be "considered" for them.

Hepatitis A infection causes inflammation in the liver, and can lead to fatigue, poor appetite, nausea and jaundice. The CDC estimates that about 21,000 new cases occur each year.

EARLIEST STATES HAVE HIGHEST RATES

To get a measure of how many teens have received the vaccine under these various recommendations, the researchers surveyed more than 20,000 parents across the country and checked the immunization records of the kids' doctors. All the kids were born between 1991 and 1997.

Among the first 11 states to receive the Committee's recommendation for routine vaccination, the vaccination rates were the highest in the country: 60 percent of kids had completed the two doses by age 13 to 17.

Alaska and Oklahoma had the highest rates, at about 85 percent.

Among these states, black, Hispanic, American Indian and Alaska Native children were more likely to have been vaccinated than white children.

Dorell said these groups were originally targeted to get the hepatitis A vaccine because they had the highest rates of infection.

"Greater efforts among these communities allow them to have higher coverage. So it looks like those groups who seemed to be most at risk are actually being vaccinated" the most, Dorell told Reuters Health.

In the six states that have had the recommendation since 1999 to consider vaccination, 39 percent of teens have received the full immunization.

"Because it doesn't say, 'routinely have all adolescents vaccinated,' there's some wiggle room," Dorell said.

As a result, the 33 states that have had the same "consideration" recommendation for teenagers for the shortest time period, since 2006, had the lowest number of teenagers being immunized: 16 percent got both shots.