Mpox Infections after Vaccination

Cases of mpox have been reported in people who have been previously vaccinated. Getting vaccinated is still very important. No vaccine is 100% effective, and infections after vaccination are possible, but they may be milder and less likely to result in hospitalization.

What We Know

Vaccine is still a shield
  • Vaccination makes getting and spreading mpox less likely.
  • Infections after any vaccination are possible. No vaccine is 100% effective.
  • If you have a rash or other symptoms of mpox, you should get tested even if you have been vaccinated or had mpox.
  • Getting vaccinated against mpox may help make the symptoms less severe and easier to manage.
  • The vaccine may help protect you against severe infection, hospitalization, and death.
  • CDC recommends getting vaccination for those who are at risk.

What We Don’t Know

Prevent mpox
  • We don’t know why people have gotten mpox after vaccination.
  • We don’t know if immunity after vaccination has decreased in these cases or how long the vaccine protects against mpox infection.
  • We don’t know if the virus has changed.

What We Are Doing to Find Out

Graphic of a patient talking with health care worker
  • We are conducting studies to determine how long immunity after vaccination lasts.
  • We are looking at specimen samples from these patients to see if the virus has changed.
  • We are working closely with our local and state partners to find out:
    • How the virus spread among these patients.
    • How many patients were vaccinated, if they were fully vaccinated, and when they were vaccinated.
  • We are closely monitoring reports of people newly diagnosed with mpox after vaccination.

What Can You Do?

If mpox is in an area where you live or are traveling to:

  • Make sure you are up to date on mpox vaccination. Get both doses of the vaccine. It’s never too late to get the second dose.
  • Seek health care and get tested if you suspect you have a rash even if you have been previously vaccinated or had mpox.
  • Pay attention to public health and community leaders for advice on how to prevent mpox exposure, including potentially changing some parts of your sex life temporarily. Recommendations may include:
    • Short-term changes to your sex life to help limit the spread.
    • Limiting new or multiple sex partners
    • Avoiding sex in places that might be associated with mpox transmission