Hantavirus and Ebola are grabbing global headlines, but measles outbreaks across the country are a bigger threat to U.S. hospitals, according to an infectious disease leader at Corewell Health.
As of May 21, the CDC had confirmed 1,952 measles cases in 2026, suggesting this year is on pace to surpass last year’s total of 2,288 cases — and potentially cost the U.S. the measles elimination status it achieved in 2000.
Matthew Sims, MD, PhD, director of infectious disease research at Corewell Health, based in Grand Rapids and Southfield, Mich., and medical director of research at Corewell Health East, told Becker’s May 20 that, compared to hantavirus and Ebola, measles is a bigger problem for the U.S.
Why measles is different
Measles is one of the most contagious diseases and can cause serious health complications, especially among children younger than 5. For every person who has measles, 9 out of 10 people of all ages around that individual will contract the disease if they are not protected, according to the CDC.
While state-specific outbreaks, including those in Texas and South Carolina, lasted a few months before subsiding, the CDC has recorded 77 new outbreaks since January 2025 — and the national case count has not stopped climbing.
“When you get infected with measles, it actually knocks down your ability to fight other infections,” Dr. Sims said. The disease can cause long-term complications and death. The CDC confirmed three measles-related deaths in 2025.
“Why are we getting big outbreaks now? Because people aren’t vaccinated,” Dr. Sims said. “The outbreaks are almost entirely in people who are not vaccinating, but once you have enough of it, it can potentially break through to people who are vaccinated, especially people who are immunosuppressed.”
Public health researchers told CBS News they are concerned about a measles outbreak in Bangladesh, which has claimed nearly 400 lives and recorded more than 56,000 suspected cases in the South Asian country. Their worries are because measles can easily travel across country borders and parts of the U.S. have a vaccination rate lower than 95% — the threshold for herd immunity, according to the CDC.
CBS News medical correspondent Céline Gounder, MD, said she is worried about measles outbreaks spreading in other parts of the world ahead of the World Cup hosted by the U.S., Canada and Mexico this summer.
“My biggest concern for the World Cup is actually measles. It’s not hantavirus, it is not Ebola. Measles is what has me concerned,” Dr. Gounder said. “We ourselves could be the source of the outbreak, because we have low levels of vaccination in certain pockets of the country, so that is my biggest concern.”
For U.S. clinicians, the challenge is compounded by unfamiliarity. Dr. Sims said he has never seen a measles case in practice — an experience shared widely among emergency physicians and other clinicians relearning how to recognize the disease.
Hantavirus and Ebola
Two outbreaks drawing international attention present a different risk for U.S. hospitals.
Eighteen Americans remain under quarantine at a Nebraska facility after exposure to Andes hantavirus aboard a 150-person cruise ship, and the World Health Organization reported more than 900 suspected Ebola cases and 220 suspected deaths in the Democratic Republic of Congo, as of May 25. No infections related to either outbreak have been reported in the U.S.
While neither outbreak poses an immediate threat compared to measles for U.S. hospitals, Dr. Sims said health systems should be prepared. The distinction, he said, lies in the infrastructure each disease demands.
What hospital infection control teams should do now
For measles, Dr. Sims recommended health systems and hospital leaders closely watch their communities for the potential spread of measles, encourage primary care physicians to explain the safety and efficacy of vaccines, and ensure their staff are familiar with signs of the illness.
For hantavirus, he said current tuberculosis-level precautions are sufficient — the virus does not spread easily, and standard isolation protocols cover the risk for most U.S. hospitals.
Ebola requires a more stringent standard. Dr. Sims said hospitals should audit whether they have the physical infrastructure to manage a case: dedicated isolation rooms with vestibules for donning and doffing personal protective equipment, which includes impermeable gowns, double masking, face shields and double gloves. If case counts abroad begin rising and the risk of U.S. exposure increases, he said, systems should begin training staff on protocols before they need them.
“We probably spent millions of dollars in training for no cases,” Dr. Sims said, recalling Corewell Health’s Ebola preparedness work during the 2014-16 West Africa outbreak. “But we were prepared.”
Ultimately, Dr. Sims said the disease posing the most immediate, preventable risk to U.S. hospitals is also the one with the clearest mitigation strategy.
“Vaccines are probably the single greatest medical boon ever created,” he said. “They have saved more lives than you can count, than you can calculate. Part of the problem is people forget the horror of these diseases.”
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