Decades ago, “Person contagious with measles visits grocery store” wouldn’t have been a news headline. It would have been any given Tuesday. Routine childhood immunizations beginning midcentury led officials to say that the disease had been eliminated in this country in 2000, but people traveling from other countries or who were never immunized also pass on the disease.
Measles is highly contagious: experts say that after a person with the disease coughs or exhales, disease-containing droplets can remain in the air for up to two hours. People don’t start to show symptoms until 7 to 21 days after exposure, and are contagious for about four days before a rash appears, and four days after it’s gone.
There’s a reason why public health officials are warning everyone who might have passed through the two establishments–the Trader Joe’s and a restaurant called Samba. If they show symptoms of measles, which at first appear a lot like a cold with red eyes, a runny nose, and a fever, they should stay home and call their doctor.
Most Americans are immunized: if you’re unsure about your immunity status, have your doctor draw titers to test your immune response.