FiveThirtyEight has a feature story on HIV prevention entitled “It Took 20 Years For The Government To Pay For An Obvious Way To Prevent HIV”. It’s a nice article, and I encourage you to read it. Needle exchanges is a simple evidence-based intervention that has drastically reduced the spread of HIV and other diseases among intravenous drug users. It’s not so obvious from reading the article that exchanging needles isn’t really a medical intervention — it’s the simple, low-cost process of letting intravenous drug users drop off dirty needles and pick up some clean needles.
I’m writing about this because Ed Kaplan of Yale (and current President of INFORMS) pioneered this work. He developed a probability model of HIV transmission and ran the initial tests by labeling needles, lending them to users, and testing the needles for HIV when they were returned. He demonstrated that needle exchanges reduce the transmission of HIV by more than 33%. And then they became a thing. There were no great ways to treat HIV back in 1991–at least by today’s standards–and even now HIV treatment is really expensive. Exchanging needles is really cheap, so it makes more sense to prevent HIV than treat HIV.
I recommend reading Ed’s seminal paper in Statistics in Medicine and the associated Interfaces article. The New York Times had a nice write up of his work back in 1991. It’s hard to overstate the importance of Ed’s work in this area. Many of Ed’s papers are cited and discussed in the 1995 Institute of Medicine report “Preventing HIV Transmission: the role of clean needles and bleach” that supported needle exchanges after a mounting body of evidence suggested that needle exchanges make a difference. I also like Ed’s 1995 article in Operations Research about probability models associated with needle exchanges. The research in this area was put into practice, and the result was lower HIV incidence and lives saved. This is a great example of how operations research can make the world a better place. Ed Kaplan may be a professor but he doesn’t live in an ivory tower.
Read more about Ed Kaplan’s research in Yale Insights.