For WA residents, does your childhood smallpox vaccine protect against monkeypox?

With global spread progressing around the United States including in Washington state, there have been claims that a smallpox vaccine can be used to combat monkeypox.

Claims regarding the effectiveness of the smallpox vaccine against monkeypox have spread across social media after The World Health Organization recently declared the global outbreak a public health emergency.

The Centers for Disease Control reports that there have been more than 22,400 cases across 79 countries around the world. Almost 99% of monkeypox cases from the current outbreak have been reported in countries that do not normally report cases of monkeypox, data from the CDC shows.

Of the 381 cases in Washington, the vast majority have been reported in King and Pierce counties.

The CDC reports that Washington is the state with the 10th-highest numbers of monkeypox cases nationally.

Can smallpox vaccines offer protection against monkeypox?

The short answer is yes. According to the CDC, monkeypox is closely related to the virus that causes smallpox. Both the CDC and the WHO have published data showing that the smallpox vaccine is 85% effective in preventing monkeypox infection.

If you do opt to get a monkeypox vaccination and don’t have a regular doctor, the Washington State Department of Health provides healthcare practitioner guidance for patients.

Are smallpox vaccines already being used as a vaccine for monkeypox?

The Food and Drug Administration has already licensed two vaccines in the past. Both the ACAM2000 and JYNNEOS vaccines are effective in combating smallpox, according to the FDA.

According to the U.S. Department of Health and Human Services, the CDC began allowing the ACAM2000 smallpox vaccine to be used as a vaccine against monkeypox last month. However, data has not yet been published to show how well ACAM2000 protects against the current monkeypox virus, according to the CDC.

Unlike ACAM2000, the JYNNEOS vaccine has been approved by the FDA since September 2019 for use against smallpox and monkeypox.

Am I protected against monkeypox if I’ve already received a smallpox vaccination?

According to the CDC, a previous smallpox vaccination does indeed provide a certain level of protection. However, in some cases, the protection does wane.

“During the 2003 monkeypox outbreak and during the current monkeypox outbreak, several people who were infected with monkeypox had previously been vaccinated against smallpox decades prior,” the CDC states on its website.

The CDC is urging everyone to take steps to protect themselves from infection, regardless of their vaccination status.

Who is eligible to receive a vaccine?

Although the Biden administration has ordered vaccine manufacturers to ramp production, the vaccines are not yet available to everyone. In some parts of Washington state, vaccine recipients are being prioritized by risk factor because of low supply.

Those eligible to receive the vaccine in Washington state include people who were exposed to someone with monkeypox, people who’ve had multiple known and or anonymous sexual partners, and men who have sex with men.