Health authorities are raising the alarm as measles cases continue to climb across the Americas, with more than 10,000 confirmed infections and 18 deaths reported so far in 2025.

According to the Pan American Health Organization (PAHO), the outbreaks are being fueled mainly by low vaccination rates. Nearly three out of four people who have fallen sick had not been vaccinated, while another 18% had an unknown vaccination status.

Countries most affected include Canada (4,548 cases), Mexico (3,911 cases), and the United States (1,356 cases). Smaller outbreaks have also been reported in Bolivia, Argentina, Belize, Brazil, Paraguay, Peru, and Costa Rica. Mexico and Canada have reported the highest number of deaths, with indigenous and unvaccinated communities hardest hit.

“Measles is completely preventable with two doses of the vaccine, which is both safe and effective,” said Dr. Daniel Salas of PAHO. “To stop these outbreaks, countries must urgently strengthen immunization and carry out targeted vaccination campaigns.”

The virus has been spreading rapidly in under-vaccinated groups such as Mennonite communities across several countries. However, health officials warn that cases are now appearing outside these groups, raising concerns about wider community transmission.

Governments are responding with vaccination drives. In Mexico, a mass campaign is underway in high-risk municipalities, while the U.S. continues to battle outbreaks in more than 40 states. Canada, meanwhile, is struggling with persistent transmission in several provinces.

PAHO is urging countries to:

Achieve 95% vaccine coverage with two doses,

Strengthen rapid response systems to contain outbreaks,

Step up vaccination campaigns in at-risk areas,

Improve communication to counter misinformation and vaccine hesitancy.

The Americas once celebrated the elimination of endemic measles in 2016. However, falling vaccination rates and ongoing global circulation of the virus have left the region vulnerable to fresh outbreaks.

Health experts are reminding travelers and families to double-check their vaccination status, especially when visiting areas with active outbreaks. Even infants as young as six months may need early protection in outbreak zones.

⚠️ The bottom line: Measles is back on the rise — but it doesn’t have to be. Vaccination remains the strongest defense to keep communities safe.