National HIV prevalence surveillance among TB patients through periodic surveys: experience in Cambodia.

SETTING The National Tuberculosis Programme (NTP) in Cambodia, one of the countries most affected by tuberculosis (TB) and human immunodeficiency virus (HIV) infection in Asia. OBJECTIVE To conduct national HIV prevalence surveillance among TB patients, to estimate HIV prevalence among TB patients and to determine the potential of the NTP as a source for antiretroviral treatment (ART) scale-up. DESIGN Anonymous unlinked cross-sectional seroprevalence surveys including all TB patients registered by the NTP in January 2003 and January 2005. RESULTS HIV prevalence among all TB patients fell from 11.8% in 2003 to 9.9% in 2005 (P < 0.05). In 2003 and 2005, respectively 265 and 261 TB patients were identified as HIV-positive in a given month. Among new smear-positive pulmonary TB patients, the prevalence dropped from 8.2% to 5.2% (P < 0.01). CONCLUSION The two periodic surveys demonstrated a high prevalence of HIV among TB patients in Cambodia. However, the declining incidence of HIV from the late 1990s might now be reflected in the HIV prevalence among new smear-positive TB patients. The NTP is a potential source of ART if HIV counselling and testing are made more widely available to TB patients.