S. together with estimates of their numbers to LY294002 supplier calculate how many foreign-born U.S. residents might be expected to have HBV infection. Weinbaum et al. estimated that out of 35,689,467 foreign-born U.S. residents in 2005, 939,416 (or 2.6%) had chronic HBV; Kowdley et al. estimated that out of 38,433,860 foreign-born U.S. residents in 2009, 1,324,693 had chronic HBV in 2009. These calculations critically depend on estimates of HBV infection prevalence in the country of origin, which may be inaccurate, and on the assumption that immigrants to
the U.S. have a similar prevalence of HBV as that of their entire country of origin, which may be untrue. Nonetheless, these staggering estimates of foreign-born U.S. residents with HBV far exceed the number of U.S.-born residents with HBV estimated at 229,000-534,000. Thus, foreign-born persons from endemic and hyperendemic countries now constitute the majority of HBV-infected patients in the U.S. Looking
at incidence rather than prevalence, and using similar methods based on estimates of HBV in the country of origin, Mitchell et al. calculated another thought-provoking statistic: C59 wnt solubility dmso U.S.-acquired new HBV infections had declined to 3,700 in 2006, while the estimated number of foreign-born persons with HBV infection who immigrated to the U.S. (“newly imported infections”) in 2006 was 62,000: nearly 17 times the U.S.-acquired number. These studies suggest that the single PAK5 most important measure to identify HBV-infected persons in the U.S. is to screen foreign-born persons from endemic or hyperendemic countries. Since 2008, the Centers for Disease Control and Prevention (CDC) has recommended HBsAg testing for all persons born in countries or regions with HBsAg prevalence of ≥2% (as well as men who have sex with men, injection-drug users, HIV-positive persons and household, needle-sharing or sex contacts of HBV-positive persons), referral of infected persons to care, and referral of close contacts for testing or vaccination. This was, in fact, an appropriate expansion of a previous CDC recommendation from 2005 to test persons from countries or regions with HBsAg prevalence ≥8%. It is important to note that although
there are many countries with estimated HBsAg prevalence ≥2% (notably most Asian countries except Japan, most African countries, and some Eastern European countries), the majority of foreign-born persons with HBV in the U.S. were born in a small group of countries in East and Southeast Asia: China, Korea, the Philippines, Vietnam, Laos, and Cambodia. These countries have both high numbers of immigrants to the U.S. as well as high prevalence of HBsAg. It is equally important to point out that foreign-born Hispanics, who constitute the majority of foreign-born persons in the U.S., have an overall very low prevalence of HBsAg, well below 2% (except those from a selected small group of countries, e.g., Dominican Republic, Haiti, and Guatemala).