On Jan. 30, 2026, the U.S. Centers for Disease Control and Prevention (CDC) confirmed 172 new measles cases for 2026, increasing a skyrocketing outbreak to 588 infections so far. And the largest outbreak in the country, in South Carolina, which started in October, has grown by 58 cases in three days, reaching 847 cases.

Last year, the CDC confirmed 2,267 cases, the most since 1991. Projecting 588 cases a month for 2026 would mean more than 7,000 total cases, though the rate of illnesses could ebb and flow as the year progresses. Last year, the country topped 600 measles cases in early April.

The huge influx is happening at a time when a top CDC official expressed little concern that the United States is on track to lose the measles elimination status it gained in 2000. Last week, Ralph Abraham, MD, the CDC’s principal deputy director, said losing elimination status is the “cost of doing business” as he emphasized “personal freedom” over vaccination, despite the wide availability of a highly effective vaccine. Abraham also wrongly tied elimination status to international travel, despite the fact that it solely has to do with locally acquired cases.

After confirming 49 outbreaks in 2025, the CDC noted the first two of 2026, involving eight patients total. The vast majority of the 588 cases are tied to outbreaks that started in 2025 and continue to expand this year. The CDC defines an outbreak as three or more related infections. Of the 588 cases this year, 94% (550) are outbreak-related. And only three are travel-related. The remaining 585 locally acquired cases were reported by 17 states.

Among patients, 27% are 5 years and younger, and 85% are in those 19 years and younger. The percent of measles patients 20 and older has dropped from 30% in 2025 to 11% so far this year. Ninety-three percent of case-patients were unvaccinated or have an unknown vaccine status. Three percent have been hospitalized, down from 11% in 2025.

The CDC notes that the measles, mumps, and rubella (MMR) vaccine is very safe and effective. MMR vaccination coverage among US kindergartners, however, has dropped from 95.2% in the 2019-20 school year to 92.5% in the 2024-25 school year, leaving about 286,000 US kindergartners at risk this school year.

The study authors note, “Measles is a highly contagious vaccine-preventable disease. Two measles, mumps, and rubella (MMR) vaccine doses are 97% effective in preventing measles.” They add, “During this investigation, testing of urine specimens enhanced case finding, especially among vaccinated persons, who might have experienced milder symptoms and potentially received a negative measles IgM test result.” Two patients who received negative polymerase chain reaction test results from nasal swabs tested positive via urine sampling.