New public health research finds only half of pregnant women receiving HIV drugs

One public health strategy endorsed by the World Health Organization (WHO) to help reduce global HIV rates is to provide the prophylactic drug nevirapine to HIV positive pregnant mothers. This drug has been shown to reduce the likelihood of HIV transmission from mother to child. After testing the cord blood after nearly 28,000 deliveries in four countries, researchers found that only 51% of women who received the prophylactic doses of nevirapine actually tested positive for that drug in their cord-blood. And about 25% of women who are given nevirapine tablets during labor do not take the pill. Women older than 25 were significantly more likely to test positive for having taken the drug compared to younger mothers.

In addition to what appear on the surface as dismal rates of drug administration, this study also raises a few other interesting points critical to public health assessment and intervention.

The use of laboratory measures to test for the drug, by actually sending cord-blood samples for analysis, was unusually rigorous for this type of research. More typically, coverage rates would be calculated based on the number of drug doses dispensed, or the number of the target population that attended sessions where they could receive the treatment. In fact, using just those types of process measures the WHO estimated that 41% of women receive HIV prevention treatment in the Cote d'Ivoire. But using the cord-blood surveillance that actually measured blood levels of the preventive agent in question, researchers found the prevalence was 16%.

Another issue is the question of "informed consent," considered a misnomer by many researchers since its been shown to involve neither informed patients, or true consent. Study sites in Cote d'Ivoire, South Africa, and Zambia, were granted informed consent waivers, meaning such consent was only sought from mothers in Cameroon, where women were asked immediately after delivery to consent to having their cord-blood tested. While identifying data was removed (month but not day of birth was recorded, and unique identifier number used instead of name), a significant amount of patient specific information was gathered, including: place of first antenatal visit, age, mode of delivery, HIV pretest counseling status, HIV testing status, whether she had received test results and prophylaxis prevent mother-to-child HIV transmission. Institutional review boards at the US Centers for Disease Control and Prevention and the University of Alabama approved the study protocol, but one might ponder whether informed consent would have been waived had such public health research taken place in Europe or the United States.

Regardless of these issues, the 51% coverage rate is disturbing enough for the researchers to assert that "worldwide implementation of services to prevent mother-to-child HIV transmission is floundering."

Photo credit: MikeBlyth