Measles outbreak surges as misinformation fuels dangerous vitamin A trend

Measles cases in the US have reached their highest level since 1991, with 2,288 infections reported in 2025. As misinformation spread online, public interest in vitamin A as a measles treatment surged, leading to a sharp rise in searches and accidental overdoses among children. The spike in measles began as vaccination rates among US kindergarteners dropped below 95%—the minimum needed to prevent outbreaks. By March 2025, 96% of confirmed cases involved unvaccinated or undervaccinated individuals.

During the outbreak, online searches for terms like 'vitamin A and measles' and 'cod liver and measles' climbed sharply. Interest peaked at 100% on March 22, 2025, after public claims suggested vitamin A could treat or prevent the disease. While vitamin A deficiency can worsen measles complications, such deficiencies are rare in the US. More concerning, incorrect dosing can cause toxicity, leading to bone thinning, liver damage, and severe headaches. Between January and March 2025, poison control centres reported 86 cases of paediatric vitamin A exposure—a 38.7% increase from the same period in 2024. Health officials have reiterated that the MMR vaccine remains the only proven protection against measles.

The 2025 measles outbreak has highlighted gaps in vaccination coverage and the risks of misinformation. With vitamin A overdoses rising, experts stress that supplements cannot replace immunisation. The MMR vaccine continues to be the safest and most effective way to prevent infection.