Do Smallpox Vaccines Protect Against Mpox (Monkeypox)?

 
According to the most recent data from the Center for Disease Control and Prevention CDC there are more than 11800 confirmed cases of mpox formerly known as monkeypox in the United States and an estimated 36500 infections globally. On July 23 2022 the World Health Organization WHO declared the global spread of mpox a Public Health Emergency of International Concern its highest alert level. 
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The good news Mpox and smallpox are closely related and smallpox vaccines provide some protection against the rapidly spreading mpox virus. Distribution of these vaccines is now rolling out to some people who are most at risk.
Infectious disease specialists Frank Esper MD and Ted M. Ross PhD break down what we know about the current vaccines available and how they can help protect against mpox.
Is there an mpox monkeypox vaccine?
The crossover between mpox and smallpox means that the prevention plan for them also matches up. According to the CDC smallpox vaccines are up to 85 effective in preventing mpox. 
These members of the poxvirus families are so closely related that if you get immunized against any one of them it actually protects against all the others Dr. Esper explains. If youre wondering chickenpox is caused by the varicellazoster virus despite its name chickenpox is not a member of the pox family viruses so if youve had chickenpox or had the vaccine you arent immune to mpox. 
Because we havent vaccinated people against smallpox in 50 years nearly half of the current U S. population doesnt have immunity to smallpox or by extension mpox. 
Teens 20 and 30yearolds are probably the most susceptible population to monkeypox Dr. Ross says. Its not surprising that youre seeing it among sexually active individuals particularly in urban settings.
Manufacturing of the original smallpox vaccine stopped in 1978. Following the September 11 2001 terrorist attacks however the United States and other governments began creating vaccine stockpiles including smallpox due to bioterrorism concerns. That led to the production of two new smallpox vaccines which are now being used to combat mpox.
When properly administered before exposure both vaccines are able to protect against mpox according to the CDC. Being vaccinated within four to 14 days of exposure to mpox may help prevent infection or reduce its severity.
The two types