number of side-effects. But we soon learned that AZT alone could reduce the risk of HIV transmission to a baby from an average of 25% down to about 8%.
This is a three-fold reduction of risk and the drug could literally be administered to the mother for the first time, intravenously during delivery and still work.
As combination therapy became available, we learned that if the mother was on therapy and undetectable at the time of delivery, the risk of transmission was extremely low (yes, U=U). Again, that’s great news; if you’re in a country where you can get combination therapy.
Sadly, that was not an option in most developing countries, even when it was the standard of care in the US and Europe. The breakthrough for low-income countries came in 2000 when it was discovered that a single dose of the HIV drug nevirapine given during delivery could reduce the rate of infection to the infant down to about 1%!
This intervention was inexpensive and low-income countries could afford it. While this was a tremendous victory, it was sort of a hollow victory to protect the baby from