The U.S. has recorded 2,231 measles cases as of July 9, 2026, already approaching the total for all of last year, with 93 per cent of cases occurring in unvaccinated people or those of unknown vaccination status.

According to the Centers for Disease Control and Prevention, the country is just 58 cases away from matching the entire 2025 measles total. The outbreak is occurring alongside a separate cyclosporiasis outbreak—a parasitic illness causing diarrhea—that has infected more than 1,500 people across 31 states.

Children aged five to 19 are most affected by measles this year, accounting for 1,122 of the confirmed cases. South Carolina has been hit hardest, with 670 cases, followed by Utah (516), Texas (182), Virginia (176), Florida (141) and Pennsylvania (103).

Measles has caused 140 hospitalizations this year, but the CDC has reported no deaths so far. This contrasts with 2025, when the outbreak resulted in three deaths—the first measles death recorded in the U.S. in a decade.

In Layman Terms

Measles is a highly contagious viral infection that spreads through coughs and sneezes. The virus can linger in the air and on surfaces for up to two hours, making it easy to catch. Symptoms—fever, rash, cough, fatigue, red eyes and runny nose—typically appear 10 to 14 days after exposure, though they can take as long as 21 days to show up.

The MMR vaccine (measles, mumps, and rubella) has been available for over 50 years. Two doses prevent measles in 97 per cent of cases; one dose is 93 per cent effective. The CDC's data shows that 93 per cent of people who caught measles this year were either unvaccinated or had unknown vaccination status, suggesting vaccination rates are a key factor in the outbreak's spread.

Why This Matters

Measles can be serious. This year alone, 140 people have needed hospitalization. Last year, three people died—a reminder that measles is not simply a childhood rash. The fact that children aged five to 19 make up half the cases means schools and families are directly affected.

The rapid pace of this year's outbreak—already nearly matching all of 2025 with months still remaining—suggests the trend could worsen. Vaccination rates appear to be a critical factor: if the pattern holds, communities with lower vaccination coverage face higher risk.

What We Still Don't Know

The source material does not explain why measles cases are rising so sharply this year compared to 2025, or whether vaccination rates have actually declined. It is unclear whether the cyclosporiasis outbreak and measles outbreak are connected or simply coinciding. The CDC data does not specify how many of the 2,231 cases are in vaccinated individuals versus unvaccinated, only that 93 per cent fall into the unvaccinated or unknown category. It is also unknown whether cases will continue to accelerate or if public health measures are slowing transmission.

Source: Forbes Business