For Scientific American Science Quickly, I'm Kendra Pier Lewis, in for Rachel Feltman.

We're listening to our weekly science news roundout.

First, we have an update on measles cases in the United States.

South Carolina's measles outbreak grew to nearly a thousand cases last week,

according to data from the State Department of Health.

The outbreak, which began last October, was part of a wave of measles outbreaks across the country that began in

2025. According to the Centers for Disease Control and Prevention, there were 50 reported

measles outbreaks last year, contributing to more than 2,200 confirmed cases and three deaths.

That was the largest number of confirmed measles cases since the U.S. was declared measles

free in 2000.

So far this year, there have been more than 1,100 confirmed cases, according to the CDC.

The vast majority have been among unvaccinated people.

The surge in cases is pushing the U.S. dangerously close to losing its measles-free status.

A country having measles-free or measles elimination status

doesn't mean that it has zero cases of measles, but rather that it has not had continuous

homegrown transmission of the virus lasting over 12 months. Canada lost its elimination status in 2025.

Spain, Austria, Armenia, Azerbaijan, the UK, and Uzbekistan, all lost their measles-free status in January.

A special meeting originally slated for April to determine if the U.S. would retain its elimination status has been pushed back to November.

Among infections that spread through human-to-human contact, the measles virus is one of the most contagious known to science. In the early days of the

COVID pandemic, much attention must pay to the coronaviruses are not, a metric used to estimate how many

people, an infected person will go on to infect. In early 2020, the World Health Organization

estimated that the coronavirus is not was between 1.4 and 2.5, meaning a person with

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