Number of measles cases on the rise worldwide, infecting 10.3 million people in 2023

According to new estimates from the World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC), there were about 10.3 million measles cases worldwide in 2023, an increase of 20% compared to 2022. Inadequate immunization coverage of globally leads to an increase in cases.

Measles can be prevented with two doses of the measles vaccine; yet more than 22 million children missed their first dose of measles vaccine in 2023. Globally, an estimated 83% of children received their first dose of measles vaccine last year, while only 74% received the recommended second dose.

Coverage of 95% or more with two doses of measles vaccine is needed in every country and community to prevent outbreaks and protect the population from one of the world's most infectious viruses for humans.

“The measles vaccine has saved more lives than any other vaccine in the last 50 years,” said Dr. Tedros Adhanom Ghebreyesus, Director General of WHO. “To save even more lives and prevent this deadly virus from harming the most vulnerable, we must invest in immunization for every person, no matter where they live.”

“The number of measles infections is increasing worldwide, putting lives and health at risk,” said CDC Director Mandy Cohen. “The measles vaccine is our best protection against the virus, and we must continue to invest in efforts to increase access.”

As a result of global gaps in vaccination coverage, 57 countries experienced major or devastating measles outbreaks in 2023, affecting all regions except the Americas, an increase of nearly 60% from 36 countries the previous year. WHO's African, Eastern Mediterranean, European, South-East Asian and Western Pacific regions have seen significant increases in cases. Almost half of all major or devastating epidemics have occurred in the African region.

Unacceptable number of deaths due to the increase in measles cases

New data shows that an estimated 107,500 people, mostly children under the age of 5, will die from measles in 2023. Although this is an 8% decrease from the previous year, far too many children are still dying from this preventable disease. This slight decrease in the number of deaths occurred mainly because the jump in the number of cases occurred in countries and regions where children with measles are less likely to die, due to better nutritional status and access to health services.

Even when people survive measles, serious health consequences can occur, some of which are lifelong. Infants and young children are at greatest risk of serious complications from the disease, which include blindness, pneumonia and encephalitis (an infection that causes brain swelling and potential brain damage).

As measles cases rise and outbreaks increase, the global elimination goal, as outlined in the 2030 Immunization Agenda, is at risk. Worldwide, 82 countries have achieved or maintained measles elimination at the end of 2023. Just this week, Brazil was confirmed to have eliminated measles, making the WHO Region of the Americas once again free of endemic measles. With the exception of the African region, at least 1 country in all WHO regions has eliminated the disease.

Urgent and targeted efforts by countries and partners are needed, especially in the African and Eastern Mediterranean regions and in fragile, conflict-affected and vulnerable settings, to fully vaccinate all children with two doses of measles vaccine. This requires achieving and maintaining highly effective routine immunization programs and providing high-quality, high-coverage campaigns when these programs are not yet sufficient to protect every child.

Countries and global immunization partners must also strengthen disease surveillance, including the Global Measles and Rubella Laboratory Network (GMRLN). Strong disease surveillance is critical to optimizing immunization programs and detecting and responding rapidly to measles outbreaks to mitigate their size and impact.

Note to editors

Progress towards regional measles elimination—worldwide, 2000–2023 is a joint publication of WHO and CDC. It was published in the WHO Weekly Epidemiological Record and CDC's Morbidity and Mortality Weekly Report. CDC and WHO use statistical modeling to estimate measles cases and deaths each year, based on cases reported by countries, and revise estimates from the previous year to assess disease trends over time.

CDC and WHO are founding members Measles and Rubella Partnership (M&RP), a global initiative to end measles and rubella. Under the umbrella Immunization Agenda 2030 and leading Measles and Rubella 2030 Strategic FrameworkM&RP's mission includes addressing the decline in national vaccination coverage, accelerating the recovery from measles setbacks resulting from the COVID-19 pandemic, and accelerating progress toward a measles- and rubella-free world. The partnership also includes American Red Cross, Bill & Melinda Gates Foundation, Gavi, Alliance for Vaccines, United Nations Foundationand UNICEF.

Measles elimination is defined as the absence of transmission of endemic measles virus in a region or other defined geographic area for more than 12 months. Conversely, a country is no longer considered measles-free if the virus returns and transmission continues continuously for more than a year.

For more information on CDC's global measles vaccination efforts, visit https://www.cdc.gov/global-measles-vaccination.

For more information on WHO's measles response and support, visit https://www.who.int/news-room/fact-sheets/detail/measles.