What’s going on: South Carolina just hit a grim milestone: It now has the largest measles outbreak in the US since the disease was declared eliminated more than 20 years ago. Cases in the state first appeared in October and have surged past 600 this year alone, with no deaths reported, according to health officials. The outbreak centers on Spartanburg County, where vaccination rates have fallen below the level typically needed to stop the spread. The majority of cases are among children who lack both recommended doses of the MMR vaccine — a pattern experts blame on vaccine opt-outs, limited health care access, and years of misinformation. Unlike last year’s outbreak in rural West Texas, South Carolina’s denser population raises the risk of sustained transmission, with linked cases already reported in North Carolina, Washington, and California.
What it means: This outbreak puts a spotlight on whether the US can still contain measles, especially as confidence in vaccines has weakened under the Trump administration. In April, the Pan American Health Organization will review US data to decide whether the country will lose its measles elimination status. A change won’t affect how outbreaks are handled per the CDC, but it does signal that outbreaks are no longer isolated or short-lived. Measles is wildly contagious. Droplets hang in the air for hours, and you can spread it four days before (and after) you even see a rash. Vaccination remains the most effective defense: Two doses of the MMR vaccine protect about 97% of people for life. And as cases rise, that protection can help limit hospital strain and preserve resources for other public health priorities.
