Johns Hopkins doctor explains why healthcare officials are "concerned" with rise in measles cases

BALTIMORE -- World Health Organization leaders this week said they are "extremely concerned" about the global rise in measles cases, which rose 79% from 2022 to 2023. 

So far this year, outbreaks have been seen in 11 states, including Maryland, with a confirmed case in Montgomery County.

Just two months into 2024 and the CDC has already reported 20 cases of measles in the U.S., compared to 58 measles cases for all of 2023. At this rate, we could see a 175% increase in measles cases in 2024.  

"It's one of the most contagious respiratory pathogens that we know of," said Dr. William Moss, the Executive Director of the International Vaccine Access Center at Johns Hopkins Bloomberg School of Public Health. "It comes on suddenly and it's really characterized by this fever and a rash." 

Moss said that, while rare, measles can cause neurological complications in children and can be deadly.

"Here in the United States many people don't realize this but, globally an estimated 100,000 to 200,000 children die of measles each year," said Moss. 

Measles has long been eradicated in the U.S. thanks to an effective vaccine developed in the 1960s, reinforced by school-entry requirements. 

Moss said the measles virus doesn't change, like COVID-19 or influenza, so the vaccine typically provides life-long protection after two doses given in childhood.

"Here in the United States, we've eliminated measles, meaning that there's not sustained transmission of measles virus in the U.S., but we still have measles cases because they're being imported from outside the country," Moss said. 

But we nearly lost measles elimination status in 2019, with more than 1,200 cases in the U.S. due to a global resurgence. 

Moss said cases in the U.S. dropped back down to 13 in 2020 due to social distancing and travel restrictions during the pandemic, but they've more than doubled every year since.

Moss said it's partially due to susceptible or unvaccinated individuals within the U.S.

"But you won't have an outbreak just with that," Moss said. "Because you have to have somebody bring the virus in."

That's why health officials are encouraging parents to get their children vaccinated against measles.

"Helping them understand that even though they're not seeing measles now, it is a threat and that the vaccine is very safe," Moss said.

Moss said, so far, we are not at risk of losing measles elimination status in the U.S. 

You can read more about the measles vaccine here.