US Measles Outbreak Surges as Vaccination Rates Plummet to 30-Year Low

Measles cases in the US have risen sharply over the past two years, reaching levels not seen in decades. In 2025, infections hit 2,288—the highest since 1991—with nearly all cases appearing in unvaccinated or undervaccinated individuals. Meanwhile, discussions around unproven treatments, like vitamin A, have surged online and in public debates. The spike in measles began in 2025, when confirmed cases climbed to 2,288. Of those, 96% involved people who had not received the full course of the MMR vaccine. The trend continued into 2026, with 2,030 cases reported in just the first six months, again mostly among the unvaccinated.

Vaccination rates among US kindergarteners had already dropped below the 95% threshold required for herd immunity. This decline left communities more vulnerable to outbreaks, as the measles vaccine remains the most reliable defence against the disease. Amid the outbreak, public figures like Health Secretary Robert F. Kennedy Jr. and podcaster Joe Rogan promoted vitamin A as a potential measles treatment. However, medical experts warn that vitamin A is not proven to treat measles and can cause serious harm if taken in excess. Overdosing may lead to short-term toxicity or long-term health problems, including birth defects in pregnant women. Despite the online buzz, vitamin A deficiency is rare in the US, as most people get enough through their diet. Yet, a 2025 study found a 38.7% increase in calls to poison control centres about pediatric vitamin A exposures in the first three months of the year. Health authorities continue to stress that vaccination, not supplements, is the safest and most effective way to prevent measles.

The US has seen a steady rise in measles cases, driven largely by falling vaccination rates. While discussions about alternative treatments persist, health officials maintain that the MMR vaccine is the only proven method to stop the spread. Without higher immunisation coverage, outbreaks are likely to continue affecting unprotected communities.