Higher risks of mother-to-child HIV transmission in countries with lower HIV prevalence: UNAIDS 2013 results for 32 countries with generalised epidemics.

objectivesDiagnosis and treatment of HIV-infected mothers significantly lower rates of mother-to-child transmission (MTCT) of HIV. Early infant diagnosis (EID) is required to monitor success of prevention of MTCT (pMTCT) programmes. Our aim was to compare rates of MTCT, EID and pMTCT in countries with generalised epidemics.

methodsThe UNAIDSinfo database includes country-level information on epidemic size, prevalence of HIV infection, EID rates and pMTCT coverage. The AIDS Spectrum model was used to estimate the number of children infected with HIV in 2013, for 32 countries with generalised epidemics. Least squares linear regression, weighted by epidemic size and controlling for GDP/capita, was used to correlate national adult HIV prevalence with estimated MTCT rates.

resultsThere were 32 countries with generalised epidemics included in the analysis (31 in Africa). Higher-prevalence countries (≥5%) had significantly lower rates of MTCT (P<0.01) than lower-prevalence countries (<5%). For 20 lower-prevalence countries (total 7.4 million HIV-infected people), there were 105,300 childhood (0-14 years) infections in 2013. In 12 higher-prevalence countries (total 17.1 million HIV-infected people), there were an estimated 107,500 childhood infections in 2013. Regression analysis suggests that if all countries achieved the same MTCT rate as Botswana (2.0%), childhood HIV infections could be cut by 88% (from 105,300 to 12,300 per year) in lower-prevalence countries, and by 82% (from 107,500 to 19,700 per year) in higher-prevalence countries.

conclusionsIn this analysis of 32 countries with generalised HIV epidemics, 49.5% (105,500/213,000) of childhood HIV infections in 2013 were in lower-prevalence countries. Targeting of prevention of MTCT in lower-prevalence countries needs to be prioritised, despite challenges, to reduce the number of children infected.