Global Measles Outbreaks

"Global Measles Outbreaks

← Data and Statistics

An outbreak means more disease than expected.

Measles is extremely contagious. Around 9 out of 10 people who are not protected will become infected following exposure to the measles virus. Measles outbreaks are declared when the number of cases reported in an area is higher than the expected number of cases.

Travelers and clinicians can check CDC’s Travel Health Notices to search for measles or other issues that may affect travelers’ health.

COVID-19 has increased the risk of measles outbreaks.

Over 61 million doses of measles-containing vaccine were postponed or missed from 2020 to 2022 due to COVID-19 related delays in supplementary immunization activities. This increases the risk of bigger outbreaks around the world, including the United States.

Measles can come to the United States from anywhere in the world.

Outbreaks can happen in areas where people may be unvaccinated or under-vaccinated, including the United States. Right now, measles outbreaks are occurring in every region of the world. Measles can enter the United States through infected travelers entering or travelling through to the U.S. as well as through infected U.S. travelers returning from other countries.

Although measles was declared eliminated in the United States in 2000, almost 1,300 cases of measles were reported in 31 states in the U.S. in 2019— the greatest number since 1992. The 2019 U.S. measles outbreaks were all linked to travel-related cases that reached at-risk populations (un- or under vaccinated against measles) in the United States..."
Measles