Once eliminated from the U.S., measles appears to be making a comeback, with 41 cases reported so far in 2024. That amount is already more than half of the total number of cases reported in 2023, according to CDC data.
While it is not the largest outbreak in recent history, the continuing trend of fewer parents deciding to vaccinate their children against the virus is causing concern among health experts.
The amount of cases already showing up as of Feb. 22 led Lori Handy, MD, associate director of the Vaccine Education Center at the Children's Hospital of Philadelphia, to predict more may be on the horizon.
"It's always challenging to predict how a disease will spread in a given year, but current vaccination rates of U.S. kindergarteners raise concern that we will see increased outbreaks instead of isolated cases," Dr. Handy told JAMA in a Feb. 28 article.
Experts worry that if the trend continues, herd immunity will drop below the level needed to maintain it and avoid additional outbreaks. And some epidemiologists are not so sure that clinicians are prepared for these pop-up outbreaks.
You can't detect what you don't understand
Since measles was eradicated from the U.S. at one point, many newer nurses and physicians may not know what its presentation looks like outside of a textbook, Thomas Talbot, MD, chief hospital epidemiologist at Nashville, Tenn.-based Vanderbilt University Medical Center and president of the Society for Healthcare Epidemiology of America, told Becker's.
Because of this, clinical leaders should prioritize doubling down on education about the virus and infection control procedures.
Even a single case is worrisome due to the virus's extremely contagious nature. According to the CDC, 20% of cases in unvaccinated individuals result in hospitalization, and 9 of every 10 unvaccinated individuals exposed to measles will also be infected.
"We still have a fairly immune population in the U.S. so I'm not as worried about a big wave of measles cases creating a surge in hospitalizations," Dr. Talbot said. "To me, though, the concern within a healthcare system is having a case introduced that people don't recognize and then spread within that healthcare facility. … A lot of clinicians, the only place they have seen measles is in a textbook or when they were in training. They haven't seen it in the patient."
Even throughout his own 25-year career, Dr. Talbot has only seen two cases of measles in person.
To be proactive in the midst of likely increasing pop-up cases of measles throughout the U.S., Dr. Talbot says hospital leaders should make sure clinicians are educated about measles and its presentation in patients; create an easy, streamlined way for nurses and physicians to order measles tests; make sure healthcare staff have received an MMR vaccine themselves; and, when in doubt or if suspecting a case of measles, isolate the patient as soon as possible, just in case.
"It's still low likelihood that folks in healthcare will see a case of measles, but when we have these outbreaks, that likelihood starts to climb," Dr. Talbot said, "and you don't want to be the healthcare facility where you don't see that measles case come in, and then you suddenly have more than one."
Waning vaccine uptake
Vaccines are also a crucial component of measles prevention, but more and more are turning away from the healthcare practice. During the 2022-2023 school year, vaccine exemptions among school age children increased in 40 states, according to a CDC report. For the 2022-2023 school year, vaccination coverage for measles, mumps, and rubella (MMR) was 93.1% — a 2% drop from the year prior.
Messaging is an important piece of discussing why measles vaccines are important to uptake, but marketing and messaging campaigns for COVID-19 vaccines fell flat, and it's important for infectious disease physicians and epidemiologists to find an approach that will work with the public, Dr. Talbot told Becker's.
"I think there's a lot of dialogue on vaccine hesitancy and how we really need to change our approach and our messaging to fit in, listening to the other side's messages, while still staying true to the science," Dr. Talbot said. "You don't want to make bold statements. Then we must make sure that we message it in a way that people receive it and that resonates with them, just like the anti-vax messages are resonating. I don't think we've really succeeded in that."