Measles Cases Rise: What Experts Want You to Know

 

Measles Cases Rise: What Experts Want You to Know

The resurgence of measles in the United States has led to the first measles-related fatalities in a decade, raising concerns and spreading misinformation about the disease. As of March 13, more than 300 confirmed cases have been reported this year, with the majority linked to an outbreak at the Texas-New Mexico border, according to the U.S. Centers for Disease Control and Prevention (CDC). The majority of those affected are unvaccinated children.

Despite the reported cases, the true extent of the outbreak may be significantly larger. 'The number of deaths suggests that the outbreak is much bigger than the official number,' states Peter Chin-Hong, an infectious disease specialist from the University of California, San Francisco. Given that measles typically causes 1 to 2 fatalities per 1,000 infections, he estimates that actual cases may be in the high hundreds or even exceed 1,000.

Recognized for its distinctive red rash, which typically begins on the face, measles can also lead to severe complications such as pneumonia, ear infections, high fever, and brain swelling. The virus spreads easily through airborne particles when an infected individual coughs, sneezes, or even leaves behind virus-contaminated surfaces. It can linger in the air for hours, and up to 90% of unprotected individuals who are exposed will contract the disease.

The Role of Vaccination in Measles Prevention

Health experts emphasize that vaccination is the most effective defense against measles. However, vaccination rates among kindergarten-aged children have dropped from 95.2% in the 2019-2020 school year to 92.7% in 2023-2024, leaving approximately 280,000 children vulnerable, according to the CDC. The decline in vaccinations has come amidst increased scrutiny of childhood immunization schedules.

'Not only does the measles vaccine prevent serious disease, it also prevents infection,' Chin-Hong explains. 'It’s a fantastic vaccine.'

Since the U.S. declared measles eliminated in 2000, annual cases have rarely surpassed 300. Typically, infections occur when travelers bring the virus from regions where it is more prevalent. The current spike in cases in early 2025 has led many to question whether a booster shot is necessary and how to recognize early symptoms of the illness. To address these concerns, Science News consulted multiple experts specializing in infectious diseases.

Early Symptoms and Disease Progression

According to Chin-Hong, initial symptoms include fever, cough, runny nose, and red eyes, which resemble many common illnesses, making early detection difficult. 'Nobody really knows it’s measles in the beginning,' he says. 'That’s why it’s so insidious and could be so transmissible.'

Within three to five days, a characteristic rash develops, typically beginning on the face before spreading downward. However, individuals are contagious up to four days before and after the rash appears. Symptoms may take up to three weeks to emerge after exposure.

Can Good Nutrition Prevent or Mitigate Measles?

There is no evidence that nutrition alone can prevent measles or reduce its spread. 'Nutrition is no substitute for vaccination,' says Scott Weaver, director of the Institute for Human Infections and Immunity at the University of Texas Medical Branch. 'There’s no evidence anywhere in the world that it prevents infection or that it prevents the spread from infected people to others.… The main way to stop this outbreak is through vaccination.'

Similarly, Larry Kociolek, a pediatric infectious disease expert, points out that good nutrition does not protect against airborne measles transmission. 'The frightening thing about measles is how contagious it is in the air. If you enter the room of somebody with measles — even if that person left that room an hour or two prior — if you’re not immune to measles, you can catch measles.'

While malnourished children are more susceptible to severe complications, measles outbreaks in high-income countries typically do not involve severe malnutrition.

Treatment Options for Measles

Weaver notes that antibiotics do not treat measles itself but may be necessary for secondary bacterial infections such as pneumonia. 'A lot of the severe infections progress to [pneumonia, which] can be caused by bacteria, and in this case, they certainly need antibiotics.'

Regarding supplements, vitamin A has been found to improve survival rates in vitamin A-deficient children in developing countries. 'If you’re vitamin A deficient and you get measles, it is very important that you get vitamin A as a treatment to reduce the severity of disease,' Kociolek explains. However, excessive vitamin A intake can be toxic, leading to symptoms such as liver damage, nausea, and brittle bones.

Currently, there is no specific antiviral treatment for measles, though ribavirin, a general antiviral drug, is sometimes used in severe cases. 'There’s no great data' supporting its effectiveness against measles, Chin-Hong says, but it remains an option due to the lack of measles-specific treatments.

How Vaccination Protects Communities

When vaccination rates are high, measles has little opportunity to spread. An infected individual can transmit the virus to 12 to 18 susceptible people, making it one of the most contagious diseases. However, vaccinated individuals serve as a barrier, limiting transmission and contributing to herd immunity. When at least 95% of a population is immunized, the community as a whole is protected.

The Misconception of “Natural Immunity”

Some believe that recovering from measles strengthens the immune system, but research suggests otherwise. 'It actually interferes with your immune system in the short run,' Weaver says. 'If you’re infected by a [measles] virus without being vaccinated, the infection suppresses your immune response for typically a few months to a few years, and that can lead to you being more vulnerable to secondary infections.'

Measles can cause immune amnesia by destroying memory cells responsible for long-term immunity. 'It turns out that measles can kill those cells.… It kills the T cells and kills the B cells. It kills the plasma cells,' immunologist Stephen Elledge explains. This loss of immune memory increases susceptibility to infections even after recovery from measles.

When Should Children Receive the Measles Vaccine?

Typically, infants receive their first measles shot around one year of age, with a second dose between ages four and six. However, in high-risk areas like Texas, health officials recommend vaccinating infants as young as six months.

'If the mother was not vaccinated or infected and that baby has no immunity, then it’s a good idea to give them the vaccine earlier,' Weaver says.

Should Adults Get a Measles Booster?

For most people, a full childhood vaccination provides lifelong immunity. 'The vaccine with two doses protects about 97% of people from getting measles again, and natural infection is probably a similar level of protection,' Weaver states.

Those uncertain about their vaccination history can consult a healthcare provider. 'If records are not available and they’re relying on memory, it’s certainly a good idea to get a booster,' Weaver advises. 'It really can’t hurt to get that booster.'