Measles Epidemic Means the Virus May Be Here to Stay

Posted by

On May 13, 2025

The measles outbreak that began in Texas with just a few cases at the end of January has now expanded to a point where some health authorities are calling it an epidemic.

The latest official count from the Centers for Disease Control and Prevention (CDC) has confirmed more than 1,000 cases in at least 30 states.

With this rapid transmission of infections, the United States is expected to surpass the measles count for 2019 (1,274 cases in 31 states), which had been the biggest outbreak since measles was declared eradicated in 2000.

The unexpected rise in the number of cases so far this year fits the CDC definition of an epidemic, but if the trend continues, scientists are also concerned that measles may once again become endemic, meaning the disease will always be present within certain geographic areas.

“The increased spread means that measles in the community could be an ever-present threat, not just confined to outbreaks,” says Peter Chin-Hong, MD, an infectious disease specialist and a professor of medicine at the University of California in San Francisco. “If the measles outbreak lasts for more than 12 months — which it is looking like it will in West Texas and New Mexico — it will be very probable that we will no longer consider measles eliminated in the U.S., because prolonged transmission of measles will continue, fueled by this very large outbreak.”

Dr. Chin-Hong notes that elimination (eradication) in the context of measles does not mean the virus is completely gone, but that transmission is at low enough levels to not be a major public health threat.

The Southwest Remains the Center, but the Problem Is Far-Reaching

The epicenter of the measles surge continues to be in Texas, and specifically Gaines County. More than 700 cases have been identified in the state since late January.

Texas and nearby New Mexico and Oklahoma account for more than 80 percent of those infected.

Most measles infections nationwide have been among young people. Children under the age of 5 make up 30 percent of illnesses, while youngsters between ages 5 and 19 make up 38 percent.

Countries elsewhere in the Americas have been affected as well, with cases reported in Canada (more than 1,000), Mexico, Belize, Brazil, and Argentina.

Measles Can Be Deadly

Measles can cause serious complications, such as pneumonia and swelling of the brain (encephalitis) that may require hospitalization. About 13 percent of those infected this year have needed hospital care. Among this group, more than 75 percent were younger than 20.

Three people have died of measles this year. Two were unvaccinated school-age children in Texas with no known underlying medical conditions, and one was an unvaccinated adult in New Mexico.

A ‘Worrisome’ Decline in Vaccination

A recent scientific report from the CDC highlights how a lack of immunization may be fueling the spread of this highly contagious rash-producing viral illness. An estimated 96 percent of this year’s measles patients were not vaccinated or had unknown vaccination status.

The authors of the CDC report stressed that measles outbreaks are becoming more frequent, especially in close-knit communities with low vaccination coverage.

Childhood vaccination rates have been falling in the United States, especially since the start of the COVID-19 pandemic, according to research published at the end of April in the Journal of the American Medical Association (JAMA).

The current U.S. measles immunization rate is considered high at above 90 percent.

But the JAMA study estimates that a 10 percent decline in the vaccination rate could lead more than 11 million people to become infected with the virus over a 25-year period.

“We’ve seen a worrisome pattern of decreasing routine childhood vaccinations,” said the senior author, Nathan Lo, MD, PhD, an assistant professor of medicine specializing in infectious disease at Stanford Medicine in California, in a press release. “People look around and say, ‘We don’t see these diseases. Why should we vaccinate against them?’ There’s a general fatigue with vaccines. And there’s distrust and misinformation about vaccine effectiveness and safety.”

Immunization Offers the Best Protection

The measles vaccine is highly effective and safe, and because there are no antiviral medications to treat measles, immunization is the best protection, according to Chin-Hong.

The CDC recommends that all children get two doses of the MMR (measles-mumps-rubella) vaccine, with the first dose coming when they’re between 12 and 15 months old and the second dose when they’re between 4 and 6 years old.

Teens and adults are advised to check with their healthcare provider to make sure they are up-to-date on their MMR vaccination.

The National Foundation for Infectious Diseases adds that all adults born in 1957 or later who have not been vaccinated or have not had measles should be immunized. If you are not sure about your status, know that it is considered safe to get another measles vaccine.

Most people who have received two doses of the MMR vaccine do not need a measles booster shot, but some specific individuals may benefit, such as those who have undergone certain treatments for cancer and have lost some immunity. Adults born between 1963 and 1967 should check with their healthcare provider to make sure they have immunity, as one formulation of the measles vaccine administered during that time period is considered less effective.

Check the CDC website for more details on measles vaccination.