Measles is a 'heat-seeking missile' experts warn as Florida outbreak grows

The Florida measles outbreak is expanding. On Friday, health officials inBroward County confirmed a seventh case of the virus, a child under age 5.

The patient is the youngest so far to be infected in the outbreak, and the first to be identified outside of Manatee Bay Elementary School in Weston, near Fort Lauderdale.

It’s unknown what connection the youngest measles case has to the school, but the spread beyond school-age kids was expected.

Cases are “not going to stay contained just to that one school, not when a virus is this infectious,” said Dr. David Kimberlin, co-director of the division of pediatric infectious diseases at the University of Alabama at Birmingham.

The Centers for Disease Control and Prevention reported that as of Friday there have been at least 35 measles cases in 15 states in 2024 — most related to international travel. In January, there were nine measles cases in Pennsylvania, eight of them in Philadelphia. (If there are no more cases reported there as of early next week, the Philadelphia outbreak will be declared over.) Late Friday,Michigan’s health department announced that it, too, had identified a measles case — its first since 2019.

Florida’s outbreak is the largest in the U.S. right now. And what Florida’s health officials are doing — or not doing — is drawing fire from experts who study the way diseases spread.

Measles is so contagious and has such a long incubation period that the decision of the state’s Surgeon General Dr. Joseph Ladapo to let parents decide whether to quarantine their children or let them keep going to school could allow cases to spread, experts warn.

“Measles is the most infectious pathogen in humans that we know of,” said Kimberlin. “It’s like a heat-seeking