evidence: Monkeypox Outbreak Expert Panel: Testing, Containment, Vaccines, and More [...] This did not work for monkeypox because many people did not know who they were in contact with and who might have been exposed. The containment [strategy] here will be getting the vaccine to at-risk individuals, [such as] a man who has sex with multiple partners, or goes to those types of events where [monkeypox has been] spread. [...] WM: Despite the fact that we're using vaccines designed for smallpox, there's not actually a whole lot of evidence around the protective efficacy of smallpox vaccines against monkeypox, although we know that there's a lot of cross-immunity with the different orthopoxviruses. One of the studies is from the early 1980s in the DRC, where they showed that individuals who had been previously vaccinated against smallpox had protection against monkeypox.