Trends and predictors of mother-to-child transmission of HIV in an era of protocol changes: Findings from two large health facilities in North East Nigeria

BACKGROUND: Research studies have demonstrated a reduction in the risk of mother-to-child transmission of HIV (MTCT) to less than 2%, or 5% in non-breastfeeding and breastfeeding populations, respectively, with antiretroviral interventions. However, the risk of MTCT in routine health-facility settings, where service delivery is usually sub-optimal needs monitoring. METHOD: We conducted a retrospective review of data from 2008–2014, in two health facilities in Adamawa State, Nigeria. Descriptive statistics were used to estimate overall MTCT rate and MTCT rate by year, and period of prevention of mother-to-child transmission of HIV (PMTCT) protocol implementation. We conducted simple and multiple logistic-regression analyses, to identify predictors of MTCT. RESULTS: Data from 1,651 mother-to-infant pairs, with HIV deoxyribonucleic acid (DNA) polymerase-chain reaction (PCR) test results from 2008 (n = 49), 2009 (n = 246), 2010 (n = 280), 2011 (n = 335), 2012 (n = 290), 2013 (n = 225) and 2014 (n = 226) were analysed. The overall MTCT rate among HIV exposed infants (HEIs) was 9.7% (95% CI 8.3% - 11.1%) at a median age of 8 weeks (IQR = 6–20). The MTCT rate decreased from 14.3% (4.4%-24.2%) in 2008 to 4.9% (2.1%-7.7%) in 2014 (p = 0.016). The MTCT rate was the lowest (5.4% [3.7% - 7.0%]) when all pregnant women living with HIV received triple antiretroviral therapy, as treatment or prophylaxis (ARVT/P). Using the pooled data, we found that infant age, breastfeeding option, antiretroviral regimen and year were predictors of MTCT. The adjusted odds of MTCT were significantly higher, when neither mother nor HEI received ARVT/P (Adjusted odds ratio (AOR) 26.4 [14.0–49.8], and lower amongst infants born in 2012, compared with those born in 2008 (AOR 0.2 [0.0–1.0]). CONCLUSION: The MTCT rate declined significantly between 2008 and 2014 in these two routine health-facility settings in Nigeria. Our study suggests that ARVT/P yields the lowest MTCT. Thus, efforts to scale up lifelong ARVT/P (Option B+) in Nigeria should be accelerated.