Children in U.S. showing higher hepatitis B immunity

According to a study conducted by George N. Ioannou from the Veterans Affairs Puget Sound Health Care System, children and adolescents in the United States have much higher rates of immunity against the hepatitis B virus than adults.

The study analyzed data from 39,787 participants of the National Health and Nutrition Examination Survey to determine the presence of the HBV infection, exposure and immunity in the United States, HealthDay reports.

Past exposures, prevalence, immunity states and associations to chronic HBV infection was determined from 1999 to 2008 by detecting the presence of serum HBV surface antigen and the serum antibody to hepatitis B surface and core antigen.

The study identified chronic HBV infection in 0.27 percent of people aged six years or older and found that 4.6 percent had been exposed to HBV, HealthDay reports. Those between the ages of six to 19 years had low rates of infection and past exposure. These estimates are much lower than the HBV exposure of 5.1 percent and 0.42 percent HBV infection rates that were estimated from 1988 to 1994. The study found high rates of immunity in children aged two years - 68.6 percent - while much lower immunity rates were detected for adults.

"A cohort of children and adolescents is growing up in the United States with high rates of immunity against HBV and very low rates of infection. Vaccination of high-risk adults should continue to be emphasized," Ioannou wrote, according to Health Day.