The Measles Outbreak Explained, According to Doctors

Between norovirus, the flu, and COVID-19, there is no shortage of illness trying to wreak havoc on our immune system. But if that wasn't bad enough, measles cases are now back on the rise. So much so that three months into the year, measles cases have surpassed the total for 2024, according to the Centers for Disease Control and Prevention (CDC).

“As a society, we should be alarmed by the re-emergence of this vaccine-preventable disease,” says Zachary Most, MD. “Since 2000, the measles virus was considered eliminated in the United States because of the efficacy of the vaccine and high vaccination rates across the country, but there is currently an ongoing outbreak that started in west Texas,” he explains.

With cases rising at an alarming rate and the first measles-related death since 2015 reported in Texas, you're likely wondering why this once-eradicated illness is back on the radar. “The measles surge is mainly due to declining vaccination rates, which make the virus easier to spread,” says Pamela Tambini, MD. “In some communities, vaccine hesitancy, misinformation, and limited access to healthcare have led to a decline in immunization coverage, and when fewer people are vaccinated, measles can spread quickly, especially among children and in close-contact settings like schools and daycare centers.”

Nationally, measles vaccination rates among kindergartners has dropped to 92 percent, with some areas in the south even lower, but to keep “herd immunity” we need to maintain a vaccination rate of at least 95 percent, says Nicholas Church, MD. And to add more chaos to the mix, misinformation about the infection is being spread left and right by a certain Secretary of Health and Human Services.

Ahead, doctors outline everything you need to know about measles and how to best stay protected.

Experts Featured in This Article:

Nicholas Church, MD, is a family medicine physician and founder of Somerset Medical.

Zachary Most, MD, is an infectious disease specialist at Children's Health and assistant professor at UT Southwestern Medical Center.

Pamela Tambini, MD, is an internal physician and medical director at Engage Wellness.

What Is Measles, Exactly?

Measles (also called Rubeola) is a highly contagious viral infection caused by the measles virus, Dr. Tambini says. “It primarily affects the respiratory system and spreads through respiratory droplets when an infected person coughs or sneezes, and it's known for its characteristic red rash, high fever, and flu-like symptoms.”

What Causes Measles?

Measles is caused by the measles virus, which belongs to the paramyxovirus family. “A person infected with measles usually has a cough, and that cough is how the virus is spread from one individual to the next,” Dr. Most says. “The infected individual coughs, projects tiny respiratory droplets into the air, and a susceptible individual can breathe in those droplets and get infected,” he explains.

And even though the infected droplets are small, Dr. Most says they can linger in the air and on surfaces for up to two hours. “In our hospital, if we see a patient with measles, we can't use that patient's room until two hours after the measles-infected person has left, because that air still contains measles virus,” he says. In other words, it's highly contagious.

Is Measles Contagious?

Yes. If you are unvaccinated, measles is one of the most contagious diseases, Dr. Tambini says. “Anyone unvaccinated is at high risk of contracting measles, but infants who are too young to be vaccinated, pregnant people, and individuals with weakened immune systems, such as those undergoing chemotherapy or living with conditions like HIV, are particularly vulnerable to severe complications (such as pneumonia, brain swelling, and even death),” she says.

Symptoms of Measles

The first sign of measles usually appears one to two weeks after exposure to the virus and typically includes the following symptoms, according to Dr. Church.

Three to five days after initial symptoms present, a “very characteristic rash” typically appears, starting on the face and head, then spreading downward to the body, arms, and legs, Dr. Most says. On lighter skin, the rash appears red, but on darker skin, it could appear purple or darker than the skin around it, according to the Cleveland Clinic. “An important thing to know about the rash is that people who have measles are infectious four days before through four days after the onset of the rash, which is part of what makes the virus so difficult from a public health perspective, because people are contagious before it's recognized they have measles,” Dr. Most explains.

In addition to the rash, Dr. Tambini says the following symptoms may present, lasting anywhere from one to two weeks.

How to Treat Measles

There is no cure or specific treatment for measles, Dr. Tambini says. Instead, management focuses on supportive care and symptom relief that includes hydration, plenty of rest, and fever or pain management, she says.

If you suspect you have measles, Dr. Church says you must call your doctor or health department before going to a clinic, hospital, or other public space to prevent the potential spread of the virus to others. From there, a healthcare professional will advise you on testing, treatment, and supportive care.

How to Prevent Measles

The best and only way to prevent measles is through the MMR (measles, mumps, and rubella) vaccination, Dr. Most says. “We have six decades of experience with the measles vaccine, and most doctors and parents have never seen a case of measles, and the reason for that is the highly effective vaccine that we've been using since the 1960s,” he says.

There's a myth that the measles vaccine causes autism, but research has thoroughly debunked this, Dr. Tambini says. “The MMR vaccine is safe, effective, and crucial in preventing the spread of measles.”

Children are typically vaccinated for measles at 12 to 15 months and then again at 4-years-old, Dr. Church says. “One dose gives about 93 to 95 percent protection, with two doses providing about 98 percent protection,” he says. Once fully vaccinated, you're immune and do not require a booster, but if you're unsure of your vaccination status, Dr. Tambini recommends talking with your doctor. From there, they can check your vaccination records and/or perform a simple blood test to check for immunity.

Finally, there is a widespread misconception that vitamin A supplementation can prevent the spread of measles, but again, this is untrue, Dr. Most says. “We know that the only way to prevent measles outbreaks in a community is for the community vaccination rate to stay very high.”

Andi Breitowich is a Chicago-based freelance writer and graduate from Emory University and Northwestern University's Medill School of Journalism. Her work has appeared in PS, Women's Health, Cosmopolitan, and elsewhere.