The declining trend of HIV-Infection among pregnant women in Cameroon infers an epidemic decline in the general population.

Background: HIV remains a generalised epidemic in Cameroon, with regular sentinel surveillance surveys (SSS) conducted among pregnant women to monitor the epidemiological dynamics, and for strategic policy making. Our main objective was to actualise data on HIV epidemiology, and compare the trends overtime among pregnant women versus data from the general population in Cameroon.

Methods: Sentinel surveillance was conducted in 2016 among pregnant women in the 10 regions (60 sites) of Cameroon, targeting 7,000 first antenatal care (ANC-1) attendees (4,000 in urban; 3,000 in rural). HIV testing was done following the serial national algorithm at the National Public Health Laboratory. Results of 2016 were compared with 2009 and 2012 dataset, alongside reports from the general population; with p < 0.05 considered statistical significant.

Findings: A total of 6,859 ANC-1 (97.99% sampling) were enrolled in 2016, with 99.19% (6,513/6,566) acceptability for HIV testing; similar to performances in 2009 and 2012 (>99%). National prevalence of HIV was 5.70% (389/6,819), similar between urban (5.58%) and rural (5.87%) settings. HIV prevalence among pregnant women declined significantly from 2009 (7.6%), 2012 (7.8%) to 2016 (5.7%), p < 0.0001; with a similar declining trend in the general population: from 2004 (5.5%), 2011 (4.3%) to 2017 (3.4%), p < 0.0001. Difference between SSS and the population-based survey was non-significant (r = 0.6; p = 0.285). Following geographical settings, HIV prevalence was higher in urban vs. rural settings from 2009-2012 (p < 0.0001), followed by similar rates in 2016. Early-age infection (15-24 years) decreased from 6.7% in 2009 to 3.4% in 2016, with remarkable declines in new infections within the age ranges 15-19 years (5.1%-1.57%) and 20-24 years (7.8%-4.39%).

Interpretation: With high acceptability in HIV testing, the prevalence of HIV-infection through SSS indicates a declining but generalised epidemic among pregnant women in Cameroon. Of note, as the declining prevalence among pregnant women also reflects an epidemic reduction in the general population, SSS represents an efficient strategy to understand the dynamics of HIV epidemics in the general Cameroonian population, pending validation by periodic population surveys.