Hepatitis B Prevalence
Hepatitis B virus (HBV) infection is a significant global health problem with five percent of the world population infected. It is responsible for over 1 million deaths per year globally, and worldwide 75 percent of persons with chronic HBV are Asians.
The World Health Organization estimates that 2 billion people worldwide have been exposed to HBV. Among them, 370 million people worldwide have chronic infection. In Asia, 8-10 percent of the population is chronically infected, and up to 50 percent of new cases are due to mother-to-child transmission.
Hepatitis B in the United States
Prevalence of chronic hepatitis B is less than 1 in 2,000 in the U.S. population. Among Asian Americans the prevalence is 1 in 10; most have not been tested and unaware of their disease.
In 2009, an estimate of the number of foreign born with chronic HBV living in the United States is more than 1.3 million, a number significantly greater than previously reported. Of those, 58 percent migrated from Asia and 11 percent migrated from Africa, where hepatitis B is highly endemic. About 7 percent migrated from Central America, a region with lower chronic disease. The total prevalence of chronic hepatitis B in the U.S. may be as high as 2.2 million. The highest prevalence exists within the Asian American and Pacific Islander American populations, where incidence can be 100 times greater than in the general population.
In the U.S., the burden of chronic HBV infection is greater among certain populations as a result of earlier age at infection, immune suppression, or higher levels of circulating infection. These include persons born in geographic regions with high (greater than eight percent) or intermediate (two to seven percent) prevalence of chronic HBV infection, HIV-positive persons (who might have additional risk factors), and certain adult populations for whom hepatitis B vaccination has been recommended because of behavioral risks.