This episode begins by asking the question, "Why is it that we don't have an HIV vaccine after 40 years, but we do have a COVID-19 vaccine after one year?" Dr. Leor Weinberger explains that the answer to this question is primarily due to the existence (or lack thereof) of natural convalescents and whether the immune system is able to beat the virus. Dr. Weinberger further explains that there have only been two "recovered" people who had HIV. These two recoveries happened through bone marrow transplants, which themselves have 50 percent survival rates. Next, Dr. Weinberger gives a history of HIV vaccine development. Then, we drill down into the specifics of why HIV has been so challenging to develop a vaccine for. Dr. Weinberger explains the role of mutation as a primary source of this difficulty, coupled with the fact that HIV inserts itself into your genome and is able to persist in the body for decades, leading to no natural convalescents. 

To conclude, we hear Dr. Weinberger's thoughts on COVID-19 vaccine specifics such as how long COVID-19 may stay with us, if we may have to get additional vaccines, and how the persistence of antibody levels factors into these considerations. We end with a discussion on the mechanisms of the COVID-19 vaccines that have been developed. For those interested, a great resource for further reading on the bioinformatics of COVID-19 vaccine mRNA can be found at https://berthub.eu/articles/posts/reverse-engineering-source-code-of-the-biontech-pfizer-vaccine/