Individuals who are at high risk of infection with the hepatitis B virus (HBV) should be screened, according to a new recommendation from the US Preventive Services Task Force (USPSTF). High-risk groups include those born in foreign countries with a high rate of HBV infection, household contacts of those with the infection, injection drug users, patients with HIV/AIDS, and men who have sex with men.
Between 700 000 and 2.2 million US individuals have chronic HBV infection, according to the task force. Many of these individuals are asymptomatic, but some will go on to develop serious conditions associated with HBV infection—liver disease or liver cancer—and 15% to 20% will die of one of these complications. Fortunately, screening tests are available that can accurately distinguish between uninfected individuals who have been vaccinated (and thus have anti-HBV antibodies in their system), those who have cleared the infection, and those who are chronically infected. But there has been some disagreement among medical groups about who should be screened.
In 2004, the USPSTF recommended against screening the general population for HBV infection, based on the conclusion that because the rate of infection in the general population was low, the benefits of screening did not outweigh the potential risks. The new recommendation applies specifically to individuals at high risk of HBV infection, and is based on newer evidence that led the group to conclude that that the benefits of treatment outweigh the risks of screening for such individuals.
People who were born in countries where the rate of HBV infection is 2% or higher account for most (47% to 95%) of the cases of chronic infection. According to the task force, high HBV infection rates are found in all the countries of Africa and Asia and most of Eastern Europe and the Caribbean. A complete list of high-risk countries can be found in the task force’s recommendation.
Others at risk include individuals who are immune suppressed, such as those living with HIV/AIDS, and individuals who may have been exposed to HBV from sexual partners, through injection drug use, or through work in occupations such as health care.
The US Centers for Disease Control and Prevention, the American Association for the Study of Liver Diseases, the Institute of Medicine, and the American Academy of Family Physicians also recommend HBV screening for those at high risk.