Measles Outbreaks Surge Across Ten Countries in the Americas in 2025

Washington, D.C., 15 August 2025 — The Pan American Health Organization (PAHO) has issued an urgent call for action as measles cases skyrocket across the Americas. As of 8 August 2025, 10,139 confirmed cases and 18 deaths have been reported in ten countries, marking a 34-fold increase compared to the same period in 2024.

📉 Low Vaccination Rates Driving the Surge

The outbreaks are largely attributed to insufficient immunization coverage:

• 71% of cases occurred in unvaccinated individuals
• 18% had unknown vaccination status

Although MMR (measles, mumps, rubella) vaccine coverage improved slightly in 2024—89% for the first dose and 79% for the second—these figures remain below the 95% threshold needed to prevent outbreaks.

“Measles is entirely preventable with two doses of a safe and effective vaccine,” said Dr. Daniel Salas, PAHO’s Executive Manager for Comprehensive Immunization. “Countries must urgently strengthen routine immunization and launch targeted campaigns in high-risk areas.”

🌍 Countries Most Affected

Country	Confirmed Cases	Deaths
Canada	4,548	1
Mexico	3,911	14
United States	1,356	3
Bolivia	229	0
Argentina	35	0
Belize	34	0
Brazil	17	0
Paraguay	4	0
Peru	4	0
Costa Rica	1	0

Mexico’s indigenous communities have been hit hardest, with a case-fatality rate 20 times higher than the general population. Canada reported a fatal congenital measles infection in a newborn.

Advertisement

🧬 Virus Genotypes and Transmission Patterns

Two genotypes of the measles virus are circulating. One has been identified in outbreaks across eight countries, especially among Mennonite communities in Canada, the U.S., Mexico, Belize, Argentina, Bolivia, Brazil, and Paraguay.

📍 Country-Specific Highlights

• Canada: Ongoing transmission in Alberta, British Columbia, Manitoba, and Ontario.
• Mexico: Mass vaccination underway in 14 municipalities in Chihuahua, which accounts for 93% of national cases.
• United States: Outbreaks in 41 jurisdictions; no new cases in Texas or New Mexico since July.
• Bolivia: Most cases in Santa Cruz; spread to seven other departments.
• Argentina & Belize: No new cases since late June.
• Brazil: 16 cases in Tocantins, mainly in a Russian Orthodox community.

🛠️ PAHO’s Response and Recommendations

PAHO is actively supporting countries with:

• Surveillance and outbreak investigation
• Laboratory diagnostics
• Expert deployment to hotspots like Mexico, Argentina, and Bolivia
• Community engagement to counter misinformation

Key recommendations:

• Achieve 95%+ immunization coverage with two doses
• Scale up mass vaccination campaigns in outbreak zones
• Strengthen rapid response systems
• Improve case detection and lab confirmation
• Engage communities to address vaccine hesitancy

PAHO does not recommend travel restrictions, but urges travelers to ensure they are vaccinated—especially children aged 6–11 months in outbreak areas.

🌐 Global Context

While the Americas interrupted endemic measles transmission in 2016, the virus remains a global threat. WHO reports 239,816 suspected cases and 108,074 confirmed cases worldwide as of July 2025. The Eastern Mediterranean Region leads with 35% of cases, followed by Africa and Europe. Source: WHO