To the Editor:

I read with great interest the article by Rein et al.1 In this manuscript, the authors attempt to address the prevalence of hepatitis B surface antigen (HBsAg) in foreign-born persons living in the United States. The authors did so by requesting data on hepatitis B screening from refugee health coordinators around the country.

The authors indicate that estimates for HBsAg prevalence from the study correspond to estimates from the literature for each country (where comparison is available). One should be very careful when extrapolating the findings of one group of refugees to an entire nation. Generally, refugees that enter one jurisdiction come from the same area in the country of origin. In sub-Saharan Africa, rates of hepatitis B virus (HBV) for each country vary according to regional areas; this is likely related to the habits and customs of each region within a country. The authors report a prevalence of HBsAg of 3.1% in refugees from Tanzania. The rates of HBsAg for Tanzania range from 4.2% in individuals negative for human immunodeficiency virus (HIV),2 9.9% in the general population,3 to 17% in HIV-infected individuals.4

Most african countries in the study by Rein et al. are areas of high endemicity for HIV.5 Prevalence of HIV infection in a population is of importance when addressing prevalence, and relevance, of HBV infection. Patients infected with HIV are known to have higher rates of occult hepatitis B.6 This means that individuals will be negative for HBsAg, with positive anticore antibody and detectable HBV viral load. The consequences of occult hepatitis B are still under investigation. However, occult hepatitis B has been reported to reactivate in patients with HIV.7 Moreover, the effects and protection of vaccination against HBV in this population are unknown. Any study attempting to address prevalence of HBsAg in individuals from African countries should take into account the presence of HIV infection, in order to better evaluate the significance of the findings.

I applaud the initiative of Rein et al. to try to achieve a much-needed clarification on the prevalence of HBsAg in refugees entering the United States. However, well-conducted prospective or cross-sectional studies with larger samples for each country are needed.


  1. Top of page
  • 1
    Rein DB, Lesesne SB, O'Fallon A, Weinbaum CM. Prevalence of hepatitis B surface antigen among refugees entering the United States between 2006 and 2008. HEPATOLOGY 2010; 51: 431-434.
  • 2
    Msuya SE, Mbizvo EM, Hussain A, Sam NE, Stray-Pedersen B. Seroprevalence of hepatitis B and C viruses among women of childbearing age in Moshi Urban, Tanzania. East Afr Med J 2006; 83: 91-94.
  • 3
    Jacobs B, Mayaud P, Changalucha J, Todd J, Ka-Gina G, Grosskurth H, et al. Sexual transmission of hepatitis B in Mwanza, Tanzania. Sex Transm Dis 1997; 24: 121-126.
  • 4
    Nagu TJ, Bakari M, Matee M. Hepatitis A, B and C viral co-infections among HIV-infected adults presenting for care and treatment at Muhimbili National Hospital in Dar es Salaam, Tanzania. BMC Public Health 2008; 8: 416.
  • 5
    Kilmarx PH. Global epidemiology of HIV. Curr Opin HIV AIDS 2009; 4: 240-246.
  • 6
    Shire NJ, Rouster SD, Rajicic N, Sherman KE. Occult hepatitis B in HIV-infected patients. J Acquir Immune Defic Syndr 2004; 36: 869-875.
  • 7
    Bloquel B, Jeulin H, Burty C, Letranchant L, Rabaud C, Venard V. Occult hepatitis B infection in patients infected with HIV: report of two cases of hepatitis B reactivation and prevalence in a hospital cohort. J Med Virol 2010; 82: 206-212.

Jose Daniel Debes M.D.*, * Internal Medicine, University of Minnesota, Minneapolis, MN.