Additional commentary and background can be found in Science;<p><a href="https://www.sciencemag.org/news/2020/10/could-certain-covid-19-vaccines-leave-people-more-vulnerable-aids-virus" rel="nofollow">https://www.sciencemag.org/news/2020/10/could-certain-covid-...</a><p>The concerns raised in this article do not speak to the efficacy of candidate vaccines using Ad5 vectors. Rather, they discuss the potential impact Antibody-dependent enhancement might have on at risk groups, and, as a consequence, for the design of clinical trials using those vectors.