ATLANTA — The United States is currently in the midst of its worst measles outbreak in 35 years, according to official figures released on Friday, July 25, 2026, amid a serious uptick in cases driven by growing vaccine hesitancy.

Since the beginning of 2026, 2,318 confirmed cases of the highly contagious illness have been recorded, according to the Centers for Disease Control and Prevention (CDC). This staggering figure surpasses the total for 2025, a year that had already shattered modern records with 2,289 cases and three deaths, including two young children.

While often dismissed as a mild childhood illness, measles can lead to severe complications, including pneumonia and brain inflammation (encephalitis), which can result in serious long-term neurological impacts or death. The disease has made a strong comeback in recent years against a backdrop of declining vaccination rates and growing distrust in public health authorities.

Experts warn that the number of cases will likely continue to rise. "I definitely believe that there is underdiagnosis," said Dr. Melissa Nolan, a professor of epidemiology at the University of South Carolina, the state that has recorded the highest number of infections this year. "When you think about the people who are choosing not to vaccinate their children, these are also the people that have medical hesitancy in general."

According to a September 2025 poll by The Washington Post and the non-profit KFF, one in six American parents actively avoid or delay vaccinating their children over fears of side effects and a lack of trust in health authorities. This erosion of public confidence has created pockets of vulnerability across the country.

Dr. Nolan emphasized that the current measles outbreak is likely only the beginning. "Measles is the first one that you tend to see these large outbreaks, because it is the most easily contagious and easily spreadable," she noted. Looking ahead, she warned, "I think we're going to start seeing more and more pertussis cases and just a variety of other vaccine-preventable diseases, unfortunately."