The long-lasting effects of HIV/AIDS

The blue line in the FRED graph above shows life expectancy at birth in sub-Saharan Africa relative to life expectancy in the United States. In the early 1960s, life expectancy in sub-Saharan Africa was 60% of what it was in the United States.

The general upward progress shown by the blue line indicates that, from the 1960s onward, sub-Saharan Africa was on a convergence path toward a life expectancy similar to that of the United States.

The HIV/AIDS epidemic of the 1980s and early 1990s set sub-Saharan Africa back 40 years on its path to convergence: The green line shows the pre-1980 trend sub-Saharan Africa was following prior to the HIV/AIDS epidemic: The blue line departs from the green line in the early 1980s and returns to it circa 2020.

Two key observations:

1. A plateau: The flat portion of the blue line, spanning the early 1980s to late 1990s, corresponds to the peak of the HIV/AIDS crisis, which affected Sub-Saharan Africa's life expectancy more severely than US life expectancy during this period.
2. An accelerated recovery: From the late 1990s onward, Sub-Saharan Africa experienced a faster rate of life expectancy increase compared with its pre-epidemic trend. This accelerated recovery has allowed the region to catch up to its pre-1980 trajectory.

Two questions:

1. Why did the HIV/AIDS epidemic affect Sub-Saharan Africa so much?
2. Why did Sub-Saharan Africa's life expectancy accelerate and eventually return to its trend, after the epidemic?

A large literature already exists on the first question, including this article. But we have no references right now to help answer the second question.

How this graph was created: Search FRED for "Life Expectancy at Birth, Total for the United States." Click on "Edit Graph." Under customize data find "Life Expectancy at Birth, Total for Developing Countries in Sub-Saharan Africa." Click on "Add." Under Formula enter b/a*100 and "Apply Formula." Go to the "Add Line" tab, click on "Create User-Defined Line" then "Create Line."

Suggested by Guillaume Vandenbroucke.