Monkeypox Vaccines Are Coming & Here's How They're Different From A Dose Against COVID-19

Monkeypox hasn’t become a pandemic-level threat like COVID-19, and U.S. officials are now rolling out a vaccine to keep it that way.

The U.S. government announced on Tuesday that it will hand out nearly 300,000 doses of monkeypox vaccine from its national stockpile, amid a mysterious global outbreak of the virus.

And yes, you read that right: they’re sitting on a stockpile of this stuff, because unlike with COVID-19, they’ve already got shots for monkeypox and smallpox, its more dangerous cousin.

The FDA-approved vaccines will be given out to people at high risk of getting monkeypox or those who have been exposed to someone with it, the White House says. Men who have sex with men are said to be particularly at risk, as the U.S. has now recorded more than 300 cases in recent months.

There are actually two approved monkeypox/smallpox vaccines available, and they each work differently from the one for COVID-19. The vaccines are about 85% effective against preventing monkeypox, the U.S. Centers for Disease Control and Prevention say.

Here's what you need to know about them, according to the CDC.

The Jynneos/MVA-BN/Imvamune vaccine

The first vaccine that U.S. officials are using is called Jynneos in the U.S., Imvamune in Canada or just MVA-BN.

Canada and the U.S. approved it for use against monkeypox in 2019, although it was being used against smallpox for years before that, the WHO says.

The vaccine is given out as two shots under the skin, with the second dose following four weeks after the first, according to the CDC.

There is “no visible ‘take’” to the vaccine, according to the CDC, so you won’t see any problems at the spot where you got the needle.

The CDC says a person is not considered immune until 14 days after they get the second dose. However, it can still help to get a dose after exposure.

This vaccine uses live virus, but it's "non-replicating," the CDC says.

Canadian officials say in their briefing about Imvamune that the vaccine doesn't contain actual smallpox, and it cannot cause or spread that disease.

The ACAM2000 vaccine

The second vaccine is called ACAM2000, and it’s a little messier than the first.

According to the CDC, ACAM2000 is given by pricking the surface of the skin a few times with a special needle, and it leaves a person with a lesion or “take” at the site.

If you get this vaccine, you have to be careful with that lesion or you can spread the live virus to other parts of your body, or other people entirely. That's because the virus is growing at the site as your body learns to fight it, the CDC says on its website.

It adds that you “must take precautions” to avoid spreading this virus after getting the vaccine. Basically, that means keeping it dry, clean and covered with a bandage that you change every few days, according to the CDC.

A person is considered vaccinated within 28 days after the shot.

The White House says this is the second-best vaccine after Jynneous, because there is a "greater risk of certain serious side effects." It's also from an earlier generation of smallpox vaccines.

Officials say they'll make sure that individuals know all the benefits and risks of this one before they hand it out.