Barely more than a week into the new year, the California Department of Public Health confirmed its first measles case of 2026.
The diagnosis came from San Mateo County, where an unvaccinated adult likely contracted the virus from recent international travel, according to Preston Merchant, a San Mateo County Health spokesperson.
Measles is one of the most infectious viruses in the world, and can remain in the air for two hours after an infected person leaves, according to the CDPH. Although the U.S. announced it had eliminated measles in 2000, meaning there had been no reported infections of the disease in 12 months, measles have since returned…