Background: Chronic hepatitis B virus (HBV) infection disproportionally affects individuals born in Africa and Asia and is the leading cause of hepatocellular carcinoma worldwide. While current guidelines recommend HBV screening for persons with high risk for infection, routine testing has not been initiated. Because HBV infection is preventable by vaccination, disaggregation of HBV infection demographic data is beneficial for targeted prevention against liver cancer.

Chronic hepatitis C virus (HCV) infection also leads to hepatocellular carcinoma and liver-related mortality. While no vaccination exists for HCV, education and early detection is important to reduce HCV transmission and complications. Screening recommendations suggest testing populations at high risk, especially people who have used injectable drugs and those who may have been exposed to contaminated medical procedures. Currently, epidemiology information for HCV infection in immigrants is limited.

This study aims to assess the prevalence of HBV infection, HBV immunity, and HCV infection among immigrants in the Baltimore-Washington metropolitan area, screened from 2009-2014, by age, gender, and country of birth.

Method: Cross-sectional data was obtained from 52 free community screening events in Washington, D.C., Maryland, and northern Virginia from November 2009 to December 2014. A total of 4439 individuals, 18 years and older participated. Each participant's blood sample was evaluated for the presence of HBV surface antigen (HBsAg) and HBV surface antibody (HBsAb). HCV antibody testing was implemented from March 2013 onward (1698 subjects). Positive results for HBV infection (HBsAg+/HBsAb-), HBV vulnerability (HBsAg-/HBsAb-, at risk for infection), and HCV infection (HCVAb+) were analyzed according to age, gender, and country of birth. Prevalence of viral hepatitis infection was calculated for African and Asian countries which were represented by at least 50 immigrant participants.

Results: Among the 4136 individuals tested, the prevalence of HBV infection was 5.1%. 41.1% were unprotected and at risk for infection, and 53.8% were protected (HBsAg-/HBsAb+). There were differences in HBsAg+ prevalence depending on birth continent: 5.8% for Asia (N = 2765), 4.6% for Africa (N = 367). High prevalence (≥ 8%) of infection was evident in immigrants from Vietnam (9.0%) and China (8.8%). Intermediate prevalence (2%-7%) was evident in Ethiopia (7.8%), Nigeria (5.1%), Korea (4.4%), and Myanmar (4.1%). Gender differences between the birth continents for HBsAg+ immigrants were significant among African immigrants (8.6% for males vs. 1.6% for females, p<.001) and Asian immigrants (7.1% for males vs. 5.1% for females, p<.05). Detected HBV infection in African and Asian immigrants differed in age patterns: highest rates were found in those in the 41-50 age group (47%) for Africa, and those 51-60 (27.8%) for Asia. For countries with at least 50 participants represented, 30.4%-54.7% of immigrants from each screened country were unprotected from HBV and needed vaccination.

The prevalence of HCV infection was 1.5% for the 1698 individuals screened. Differences in prevalence were seen in birth continent, with 1.5% for Asia (N = 1206) and 2.4% for Africa (N = 150). Myanmar had the highest prevalence at 4.6%. Gender differences in HCV infection by birth continent were not statistically significant. HCV+ Asian and African immigrants differed by age group: highest rates were found in those in the 71+ age group (33.3%) for Africa, and those 31-40 (33.3%) for Asia.

Conclusion: This study suggests better estimates of the true burden of HBV and HCV infection among immigrants from Asia and Africa. By disaggregating screening data into age, gender, and country of birth, programs for prevention, earlier diagnosis, and linkage to care can be improved.

Citation Format: Emmeline Ha, Frederic Kim, Jane Pan, Dan-Tam Phan Hong, Hee-Soon Juon. Prevalence of viral hepatitis B and C infection among immigrants in the Baltimore-Washington metropolitan area screened from 2009-2014. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr B37.