Subject: Measles
Measles. This year is off to a rough start—the worst January in more than 30 years. The U.S. has already reported hundreds of measles cases. That’s especially concerning because January is usually a slower month for measles. School breaks often slow spread, and temperatures help measles peak later, closer to spring.


Number of measles cases in the United States. Source: CDC; Annotated by Your Local Epidemiologist.
Most of the cases are coming from a large and fast-growing outbreak in South Carolina:

243 cases in just the past 10 days
558 total cases since October
96% of cases are unvaccinated
90% are children