Pan American Health Organization (PAHO) issues new epidemiological alert,Due to the rapid spread of the measles virus in the region, the organization called for an urgent vaccination campaign, stressing that 78% of recent cases involved unvaccinated people.It comes after a surge in measles cases in the Americas, with Mexico reporting the highest number of cases. Canada lost its measles-free status last November, and the United States and Mexico may soon do the same.
Although both the U.S. and Mexican governments have requested a two-month extension of their respective epidemic control periods, the situation has been further complicated by the Trump administration's withdrawal from the World Health Organization (PAHO's parent agency) in January this year.
This year, the Americas will also host some world-class events, such as the 2026 FIFA World Cup, which will be held in these three countries where measles cases have surged.
Measles is an acute respiratory infectious disease caused by the measles virus, characterized by fever and rash. It is highly contagious and can easily cause outbreaks.
vaccine dilemma
In the first three weeks of 2026, PAHO confirmed 1,031 new measles cases in seven countries, a 43-fold increase compared to the same period last year. Although no deaths have been reported yet, the epidemic remains highly concentrated: Mexico tops the list with 740 cases, followed by the United States (171 cases) and Canada (67 cases).
The outbreak in the United States is particularly worrying. What is even more troublesome is that U.S. Secretary of Health Robert F. Kennedy Jr. is also a staunch anti-vaccinationist. Under his leadership, American schools and other public institutions have canceled the policy of compulsory vaccination, which has been criticized by health experts for exacerbating the spread of the measles virus.
Measles cases have been reported in at least 17 states in the United States, with at least 500 people infected in Utah and Arizona, and more than 870 confirmed cases in South Carolina, most of them children and teenagers.
The Pan American Health Organization noted that measles cases have continued to increase over the past year and reached the highest level in five years, mainly due to a global rebound in the epidemic and persistent immunization gaps. Only 33% of countries in the Americas have reached the threshold of 95% vaccination coverage for the first dose, and only 20% have achieved this threshold for the second dose.
At the same time, while adolescents and young adults account for the vast majority of cases, the highest incidence rates are among children under 1 year old, a disparity that highlights the urgent need to increase second-dose vaccination coverage.