People who have had chickenpox are still at risk for monkeypox infection. Monkeypox virus is categorized as a genus of poxviruses in the family Poxviridae, and is one of the four genera of poxviruses that cause disease in humans, the other three being smallpox virus, poxvirus and cowpox virus. Chickenpox is an infection induced by varicella-zoster virus. Although it also shows clinical manifestations of rash and blisters, it is completely different from monkeypox virus, and there is no immune cross-protection between the two. Therefore, for people who have suffered from chickenpox, their body’s antibody protection against the monkeypox virus will not have any effect. However, since monkeypox virus is categorized in the poxvirus family, smallpox virus has a certain homology with it, and it has been scientifically proven that there is a certain degree of cross-protection against monkeypox virus in people who have been vaccinated against smallpox in the past. At the same time, human beings have long overcome the smallpox virus and some people have been vaccinated against smallpox, so people who have been vaccinated against smallpox can effectively avoid the risk of monkeypox infection.