BANGKOK — The U.S. reported its first measles-related death since 2015 this week, affecting an unvaccinated child in rural West Texas.

Typically, most U.S. measles cases originate from individuals who have traveled internationally. Texas officials have so far reported 124 cases, while New Mexico has reported nine.

Experts attribute the rise in cases to declining measles vaccination rates globally since the COVID-19 pandemic. In the U.S., most states now fall below the 95% kindergarten vaccination threshold needed for community-wide measles protection.

In 2024, Britain reported 2,911 confirmed measles cases, marking the highest annual number since 2012.

Last year, measles cases in the United States nearly doubled the total for 2023, raising concerns about the resurgence of this preventable childhood illness. Health officials confirmed measles cases in at least 18 states in 2024, including New York City, Philadelphia, and Chicago.

“Measles anywhere is a threat everywhere,” according to the U.S. Centers for Disease Control website.

Here’s an overview of the global measles situation.

Are measles outbreaks common outside the U.S?

The World Health Organization estimates that 10.3 million people contracted measles, resulting in 107,500 deaths. The majority of cases occurred in unvaccinated individuals, particularly children under five. Infections were most prevalent in parts of Africa, the Middle East, and Asia with low incomes and insufficient healthcare.

Approximately 10.3 million people were estimated to have been infected with measles in 2023.

In regions where measles has been largely eliminated, cases have been introduced by travelers from other countries.

While measles-related deaths saw a slight decrease in 2023, the number of outbreaks increased. Significant outbreaks occurred in 57 countries during 2023, including India, Indonesia, Russia, Yemen, and Iraq. The Democratic Republic of the Congo recorded the highest number of cases in 2023, with 311,500.

What is the impact of vaccinations?

The global rate of childhood vaccinations has decreased in recent years, falling from 86% in 2019 to 83% in 2023, partly due to disruptions in immunization and healthcare caused by the pandemic.

The WHO estimates that vaccinations averted over 60 million deaths globally between 2000 and 2023, driven by increased vaccination efforts. In 2000, an estimated 800,062 people died from measles. Before the vaccine’s introduction in 1963, major epidemics caused about 2.6 million deaths annually.

The WHO states that a 95% immunity rate is necessary to prevent measles epidemics, due to the virus’s high contagiousness. In other words, approximately 9 out of 10 non-immune individuals will contract the virus upon exposure.

What international efforts are underway to prevent epidemics?

The WHO and other organizations support the “Immunization Agenda 2021-2030,” which aims to eliminate measles.

Independent experts declared the Americas free of endemic measles in 2016, but this status was lost in 2018 due to outbreaks in Brazil and Venezuela. Experts say that reduced vaccination rates are hindering efforts to fully eradicate the disease.

Global health organizations and other groups have intensified their efforts to accelerate immunization programs and address prevention gaps.