The Angola HIV epidemic, 2004–11: a case of change or stability?

• Published in: The Lancet (British edition) 2013-11, Vol.382 (S2), p.S17-S17
• Main Authors: Catumbela, E, Dr, Freitas, A, PhD, Serrano, D, MD, Furtado, M L, MD, Gomes, M, MD, Shiraishi, R W, PhD, Young, P, MD PhD, Naffga, N, MD, Hall, D Love, MD, Mendoza, M C T, MD, Costa, C, PhD, Sarmento, A, MD, Costa-Pereira, A, MD
• Format: Article
• Language: English
• Subjects: at-risk population; blood; cross-sectional studies; disease outbreaks; Disease transmission; Epidemics; health care workers; HIV; Human immunodeficiency virus; Internal Medicine; monitoring; Polls & surveys; Pregnancy; pregnant women; Public health; selection criteria; seroprevalence; Sexual behavior; Sexually transmitted diseases; STD; surveys; Syphilis; Treponema pallidum
• ISSN: 0140-6736; 1474-547X
• DOI: 10.1016/S0140-6736(13)62265-5

Abstract Background In Angola, HIV transmission occurs mainly by unprotected sex. To characterise the epidemic accurately, sentinel surveillance activities must reach those population groups who are sexually active. Surveillance in pregnant women in antenatal clinics is considered an effective way to do routine epidemiological surveillance of HIV in countries with generalised heterosexual HIV epidemics. Angolans experienced 37 years of war that ended in 2002, and concerns have been raised about HIV prevalence since that time. Reliable data for HIV prevalence among pregnant women presenting to antenatal clinics have been available only since 2004, with previous survey results showing prevalence of 2·7% (95% CI 2·5–3·0) in 2004, 2·8% (2·5–3·1) in 2005, and 3·2% (3·0–3·5) in 2007. We assessed trends in the HIV epidemic in Angola and explored whether there has been an increase in HIV prevalence in Angola during the 8-year period following the war, between 2004 and 2011. Methods We did a cross-sectional survey of HIV-positive pregnant women in 36 sentinel sites in 18 provinces of Angola in 2009 and 2011, to assess HIV prevalence. Participants were recruited consecutively as they presented for care until either the calculated sample size per site (500 women) or a 12-week time limit was reached. Selected women were aged between 15–49 years, had a pregnancy confirmed by a health-care professional, attended the antenatal clinic for the first time during the current pregnancy, and had accepted a test for syphilis. Participants received information from the nurse about HIV surveillance and provided verbal consent for remaining blood to be used for HIV testing. Women who were referred from another antenatal clinic within 3 months before their first visit, or who refused syphilis testing or treatment, were excluded from participation. These selection criteria were used in previous surveys. We calculated mean prevalence (with 95% CIs) for each province and for each year. χ2 tests were done to assess HIV prevalence trends during the 8-year period (2004–11). Findings During the 2009 and 2011 seroprevalence surveys, data from 17 441 and 17 988 pregnant women were collected, respectively, and aggregated HIV prevalence was 2·8% (95% CI 2·5–3·0) in 2009 and 3·2% (2·9–3·4) in 2011. In both years, considerable variation occurred across provinces, ranging from 1% (0·5–1·8) in Kwanza Sul to 4·4% (3·5–5·6) in Cunene in 2009, and from 0·3% (0·1–0·9) in Uíge to 5·8% (4·1–8·2) in Bié