Given the recent identification of measles clusters and cases in countries in the Americas Region, the Pan American Health Organization / World Health Organization (PAHO/WHO) recommends that Member States continue to strengthen vaccination, epidemiological surveillance, and rapid response activities, especially in populations known to be reluctant to be vaccinated and in communities surrounding or hosting these populations. The implementation of active community, institutional, and laboratory searches, in addition to complementary vaccination activities to close possible immunity gaps, is also recommended.
Global overview
According to monthly measles and rubella surveillance data published by the World Health Organization (WHO) in 2024, as of 15 October 2024, 502,657 suspected measles cases were reported in 182 Member States in the six WHO regions, of which 283,667 (56%) were confirmed. 1 In 2023, 623,410 suspected measles cases were reported in 176 WHO Member States, of which 321,922 (52%) were confirmed1 (1, 2).
Summary of the situation in the Americas Region
In 2024, between epidemiological week (EW) 1 and EW 40, in the Americas Region, there have been 14,373 suspected measles cases, of which 376 cases have been confirmed in Argentina (n= 11), the Plurinational State of Bolivia (n= 3), Brazil (n= 2), Canada (n= 82), the United States of America (n= 267), the Turks and Caicos Islands (n= 2), Mexico (n= 7), and Peru (n= 2) (Figure 1) (3, 4, 5, 6).
The distribution of confirmed cases by EW shows an increase in cases starting from EW 7 of 2024, with the maximum number of cases recorded in EW 12. Since EW 13 of 2024 there has been a general downward trend that continued up to EW 40. According to the information available on the confirmed cases, the age groups with the highest proportion of cases were those aged 1-4 years, 5-9 years, and 20-29 years, with 26%, 25%, and 25%, respectively. Regarding vaccination history, 57% of cases were not vaccinated, while this information was unknown or absent in 28% of cases (Figure 2) (4).