Mpox Vaccine

The mpox vaccine is a shot that reduces your risk of the viral illness mpox. There are a few different types of mpox vaccines, but the MVA-BN (JYNNEOS™) vaccine is recommended in the U.S. You receive two doses 28 days apart.

The vaccine uses a virus similar to mpox (MVA-BN, a version of vaccinia virus) to get your immune system to recognize mpox. That way, if you’re later infected with mpox, your body should have the tools to fight it off so you don’t get sick or don’t get as severely sick. Scientists weaken the virus for use in the vaccine, so it can’t make more copies of itself or make you sick.

How do you get the mpox vaccine?

A provider gives you the vaccine as a shot. They can give it either between the top layers of your skin (intradermal) or into the layer of fat under your skin (subcutaneous). Providers usually give intradermal shots in your forearm and subcutaneous shots in the back of your upper arm.

How often do I need it?

To be fully vaccinated, you’ll receive two doses at least 28 days apart. You generally don’t need additional doses. If your job puts you at a higher risk for exposure to mpox, you may need an additional dose after 10 years.

What are the mpox vaccine recommendations?

Recommendations for getting mpox vaccines are based on who’s at a higher risk. Your provider might recommend getting vaccinated if you’ve been exposed to mpox, or if you’re likely to be exposed to it. You might be at higher risk if you:

• Have been in close contact with someone with mpox
• Live in an area where mpox is spreading
• Have traveled to or will travel to an area where mpox is spreading
• Work in healthcare (caring for people with mpox or diagnosing it in a lab)
• Have been diagnosed with one or more sexually transmitted infections (STIs) in the past six months
• Have had sex with more than one person in the past six months
• Have had sex at a sex club, bathhouse or another commercial sex venue in the past six months
• Have a sex partner who’s at a higher risk

Talk to a healthcare provider if you’re wondering if you should get vaccinated. They can talk with you about the most up-to-date recommendations. Let them know if:

• You have a weakened immune system
• You’re pregnant or could be pregnant
• You’re breastfeeding
• You’ve recently had mpox

Sharing this information helps your provider plan the safest care for you.

Side effects and risks

Side effects of the mpox vaccine may include:

• Pain, swelling, itching, redness or discoloration where you got the shot
• Tiredness
• Headache
• Muscle aches
• Fever
• Nausea
• Chills

Rarely, the vaccine may cause an allergic reaction. Go to the nearest ER or call 911 (or your local emergency service number) if you have symptoms of a severe allergic reaction, including:

• Swelling of your face, tongue or throat
• Difficulty breathing
• Dizziness
• Weakness
• Fast heart rate
• Hives

Will it leave a scar?

The intradermal vaccination may cause a raised scar (keloid) to develop. Talk to the provider giving the shot if you’re concerned about a scar. You can request a subcutaneous vaccination or talk to them about getting the shot in a concealed spot on your body.

How effective is the mpox vaccine?

Some studies suggest that two doses of the MVA-BN mpox vaccine are around 82% effective at preventing mpox if you get them before being exposed to mpox. Others report that two doses are up to 99% effective.