​In recent years, Latin America has witnessed a concerning resurgence of diseases that, until recently, were considered controlled thanks to vaccination programs. Measles, whooping cough, and yellow fever have returned with force in several countries in the region, raising alarms among health authorities and highlighting the consequences of declining immunization rates.

According to recent data from the Pan American Health Organization (PAHO), as of 2025, there have been 2,318 reported cases of measles in the Americas, with 98% concentrated in the United States, Canada, and Mexico. Mexico, in particular, is facing a severe whooping cough outbreak, with more than 800 cases and 48 deaths—all in infants under one year of age. Colombia, meanwhile, has declared a health emergency after confirming 83 cases of yellow fever, an alarming number considering that in the past decade, only 11 cases had been reported.

The causes of this setback are multiple. The COVID-19 pandemic disrupted routine vaccination programs, and the rise of anti-vaccine movements has sowed doubt about the safety and effectiveness of immunizations. Additionally, logistical problems, vaccine shortages, and a lack of awareness campaigns have contributed to only 16% of countries in the region reaching the coverage level required to prevent measles outbreaks.

In response, governments have started taking action. Mexico launched its first National Vaccination Week since the pandemic, aiming to administer 14 vaccines included in the 2025 National Vaccination Schedule. In Colombia, authorities have intensified immunization campaigns in high-risk areas, especially in departments like Tolima, where the yellow fever outbreak is concentrated.

PAHO has emphasized the urgent need to close vaccination coverage gaps and strengthen epidemiological surveillance to prevent these diseases from becoming endemic again. History has shown that vaccination is one of the most effective tools to prevent disease and save lives. It is imperative that the region regain lost ground and ensure equitable access to vaccines for all its inhabitants.

In 2025, the Americas face a troubling resurgence of vaccine-preventable diseases such as measles, whooping cough, and viral hepatitis. This trend is attributed to declining immunization rates, misinformation, and interruptions in public health programs.

Measles:

• United States: As of April 2025, there have been 884 measles cases, with active outbreaks in at least 10 states, including Texas, New Mexico, Oklahoma, Kansas, Indiana, Michigan, Montana, Ohio, Pennsylvania, and Tennessee. Texas is the most affected, with 663 confirmed cases and three reported deaths.

• Canada: Ontario has reported 1,020 cases from October 2024 to April 2025, one of the most significant outbreaks in the region.

• Mexico: The state of Chihuahua has recorded 786 cases and one measles-related death. Authorities have stepped up vaccination campaigns to contain the outbreak.

Whooping Cough:

• United States: 8,485 cases have been reported in 2025—double the number from the previous year. Michigan recorded 497 cases, and Louisiana reported two infant deaths in the past six months.

• Mexico: As of April 2025, 809 cases of whooping cough and 48 deaths (all in infants under one year) have been confirmed. The government has implemented vaccination for pregnant women to protect newborns.

• Guatemala: Between January and March 2025, 14 suspected cases and 7 confirmed cases were reported, mainly in the departments of Sacatepéquez and Guatemala.

• Peru: 293 cases of whooping cough have been reported so far this year, with significant outbreaks in the Cusco and Loreto regions.

Viral Hepatitis:

• Argentina: A 456% increase in hepatitis A cases has been observed, with 50 cases recorded in 2025. Additionally, there have been 206 cases of hepatitis B and 385 of hepatitis C, representing increases of 13% and 17% respectively compared to previous years.

• Colombia: In recent years, more than 2,000 cases of viral hepatitis have been reported, with a notable rise in the southern regions of the country.

PAHO has urged countries in the region to reinforce vaccination programs and enhance epidemiological surveillance to prevent the spread of these diseases. Cooperation between governments, international organizations, and civil society is essential to protect public health and prevent these illnesses from becoming endemic again in the region.