The Sentinel

Measles cases reach 600: Experts warn of contagion risk and vaccine importance

by Matt Sheehan
OSF Healthcare

PEORIA - As measles cases continue to climb across the United States, the long-term implications can’t be ignored.

The respiratory viral infection, although thought eliminated in the U.S. in 2000, has reemerged, especially among unvaccinated individuals. As of early April 2025, the Centers for Disease Control and Prevention (CDC) has reported more than 600 confirmed cases of measles.

Measles is extremely contagious

"The key to measles is how highly infectious it is. Each person that has measles will infect between 12 and 18 people in an unvaccinated situation," says Doug Kasper, MD, an infectious disease specialist with OSF HealthCare. "The key for controlling measles is widespread vaccine use."

Doug Kasper, M.D.
OSF Infectious Disease Specialist

For reference, each influenza patient, on average, will infect one to two others.

The measles vaccine is normally offered once a child has reached one year of age. It's a two-shot series, which came on the market in 1963. Dr. Kasper says this gives medical experts decades of data that show a correlation between people receiving the vaccine, and close to zero circulation of the virus in the United States.

The states with measles outbreaks are in unvaccinated people, and no breakthrough cases (in those who have received the vaccine) have been reported, Dr. Kasper adds.

The long-term risks for unvaccinated measles patients

"There is emerging information that vaccination not only protects an individual from not becoming ill or having less severity of illness with a viral exposure, whether that's measles, chicken pox, influenza or COVID-19, but that there are long-term risks from viral infections that we do not appreciate in the moment," Dr. Kasper says. "Some of these have been associated with memory loss or dementia as somebody ages. Some of these are associated with organ disease like hepatitis or kidney disease."

Subacute Sclerosing Panencephalitis (SSPE)

SSPE is a rare, deadly degenerative disease of the central nervous system that can happen seven to 10 years after a measles infection. Young children, pregnant women and immunocompromised people are the most at-risk for SSPE. One to three out of every 1,000 children who become infected with measles will die from respiratory and neurologic complications, the CDC says.

SSPE symptoms happen over four stages.

Stage 1: Personality changes, mood swings or depression. There may also be fever and headaches, this stage can last up to six months
Stage 2: Muscle spasms and uncontrolled movement problems. Loss of vision, dementia and seizures can occur
Stage 3: Twisting movements and rigidity. Sometimes death
Stage 4: Serious brain damage, including areas of the brain that control breathing, heart rate and blood pressure, leading to coma and death

Immune amnesia

Another long-term impact of measles is known as immune amnesia. The American Society for Microbiology (ASM) calls immune amnesia “one of the most unique and most dangerous features of measles pathogenesis.” The extremely rare condition causes people’s immune systems to “forget” how to fight off infections and makes the person more susceptible. The ASM determined it normally takes two to three years after a measles infection for protective immunity to return.

A measles outbreak was declared in Northeast Illinois in early 2024 and declared “over” by the Illinois Department of Public Health (IDPH) in June. The expectation of statewide health experts is that measles will return to Illinois in the coming months. This is mainly due to heavy travel through Chicago airports and summer festivals. County health departments have now been tasked with keeping an eye on their measles vaccine rates and identifying areas where vaccine rates are low.

Peoria County's measles vaccine rate is quite high, around 95%. But outlying communities in central Illinois have lower vaccine rates, normally more rural counties. Health experts at Michigan Medicine call the Great Lake State “ripe for a measles outbreak,” as only 66% of toddlers receive the recommended childhood immunizations.

Measles symptoms

"Measles typically presents with a high fever, typically much higher than what we'd see with seasonal colds or influenza. Fevers can be 104 or 105 degrees Fahrenheit," Dr. Kasper says. "That's followed by a runny nose and a characteristic rash. This typically develops on the head and then spreads down the rest of the body."

“We don’t want to go back”

"Measles at its peak, in the 1950s before the vaccine, led to a significant number of hospitalizations in young children. Around 50,000 hospitalizations were estimated per year and about 500 deaths," Dr. Kasper says. "We don't want to go back to that scenario in any capacity, where we have a large number of unvaccinated people. The outcomes could be too severe."

Immunocompromised people like those who have received an organ transplant, cancer patients or those on long-term therapies that could impact their immune system, are at high risk for measles.

Why vaccines are so important right now

Summer travel along with large crowds at places like airports and theme parks, will likely bring more measles cases to the United States.

"This time, as good as any time, is to make sure somebody is updated on their vaccinations. If somebody isn't sure if they were vaccinated as a child, they should talk to their primary care provider about testing or receiving the vaccine. If someone is immunocompromised and they might be at a higher risk for measles through travel in areas that have exposure, they should talk to their primary care provider about the vaccine," Dr. Kasper says. "If someone has young children or is at an age where vaccine is recommended, we wholly recommend for them to discuss with their provider to remain up to date on their vaccine series."

Vaccine hesitancy continues to be a topic of discussion, one that Dr. Kasper recommends patients openly discuss with their medical provider.

Natural immunity is not a viable option with measles. The highly infectious nature of the virus, along with the severity of symptoms and potential for long-term complications, make it an illness people need to try and avoid entirely.

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Facing inequities in maternal health care, Black mothers are more at risk to receive lower quality care

For Black women, one of the biggest issues is finding their voice when confronting health issues.

by Paul Arco
OSF Healthcare

As a practicing OB/GYN, Lisa Davis, MD, sees the maternal health challenges Black women deal with every day.

Lisa Davis, M.D.
OSF HealthCare Saint Anthony Medical

“Some of the issues that face black women when it comes to maternal health are issues with blood pressure,” says Dr. Davis, chief medical officer for OSF HealthCare Saint Anthony Medical Center in Rockford, Illinois. “So what we would call preeclampsia, a risk of preterm birth, which can result in low birth weight of the infant, postpartum hemorrhage, or hemorrhage that occurs right after delivery or during the latter stages of delivery.”

And it can lead to even more serious consequences. According to the Centers for Disease Control and Prevention (CDC), the pregnancy-related death rate for Black women is three times the rate for mothers of other racial and ethnic groups.

Nationally, April 11-17 is Black Maternal Health Week, a time to raise awareness and take action to improve the health of Black mothers.

Dr. Davis says for Black women, one of the biggest issues is finding their voice when confronting health issues, which include disparities such as getting quality healthcare, dealing with underlying chronic conditions and social drivers such as income, housing, transportation or child care.

Dr. Davis stresses to her patients the importance of making their own health a high priority.

“I think for black women in the maternal health space, it's being heard and too often, there is a misperception that sometimes is out there regarding their response to pain, their use of drugs and things that are all misconceptions,” she says. “That is a big challenge for us, and that includes me, to overcome. It doesn't matter what level of education or where you live. The research has shown that it is still an issue.”

Dr. Davis adds that the medical community can do better when it comes to listening and responding to their patients’ needs. “Every patient is special and different for us to slow down and really look at that person as the person, and understand and listen,” she says. “Sometimes patients, if they're not comfortable, won't disclose what's going on in the first few minutes, but as you get ready to leave, then you might start to get the real back story. And so, it's important for us to slow down and be in the moment.”

Another need is for more Black providers, according to Dr. Davis. She says studies have shown that Black patients tend to relate to someone their own color. “It's very important, I think, for that message to be out there and to encourage young people to look at health care as an option, especially young people of color, because in the future, that's what we're going to need.”

But there are things patients can do for themselves. Dr. Davis stresses to her patients the importance of making their own health a high priority. That includes maintaining a healthy diet, getting enough rest and exercise and attending prenatal appointments.

“If you're not at your best, how can you be good for anyone else?” she asks. “I think what moms suffer from is everyone's important, but sometimes they need to take that step back and focus on themselves, so they can be 100% for their kids, for their spouse, for their parents, for their siblings.”

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