Though measles was declared “eliminated” in the United States in 2000, it has never fully gone away. In 2025, the country has seen three outbreaks already (which the Centers for Disease Control defines as three or more cases), and the virus has continued to spread.
As of the end of February, more than 160 cases have been reported across Alaska, California, Georgia, Kentucky, New Jersey, New Mexico, New York City, Rhode Island and Texas, with one death in Texas (an unvaccinated school-aged child). The highest concentration of this outbreak is in Texas, with more than 100 cases in that state alone.
With this elevated risk of contracting measles, some people are now wondering if their vaccines are working to protect them from this contagious virus — and if they need another vaccination on top of the shots they may have already gotten. Here’s what the experts have to say.
What is measles?
Measles is a highly contagious virus with a number of symptoms to look out for — most notably a rash and fever, according to the CDC. The virus is spread through the air, and once infected, measles attacks your respiratory tract. The Cleveland Clinic notes that there is no cure for measles and measles just has to “run its course.” However, the best protection from it is a measles vaccine, which is typically given to babies in the form of the MMR (measles, mumps and rubella) vaccine.
Measles typically manifests at first as a “very specific rash that starts from the face and spreads down your body,” says Dr. Yoshua Quinones, board-certified internist with Medical Offices of Manhattan and contributor to LabFinder. Other common side symptoms to watch out for include “high fever, cough, runny nose and watery or red eyes.”
Quinones adds, “Occasionally, you may see small white spots inside your mouth. These are named Koplik spots.”
While measles can and will make anyone sick, the CDC reports that it is especially dangerous for children under 5 years old. This is because children have undeveloped immune systems and are at a higher risk of illnesses, making them vulnerable — and it’s even more so if they haven’t been vaccinated.
What is the measles vaccine?
The measles vaccine protects people from getting measles. It’s known as the MMR, since it’s combined with the vaccines for mumps (a contagious viral infection that affects the salivary glands) and rubella (another contagious viral infection that typically starts with a red facial rash). You may also see the MMRV, which includes a vaccine for varicella or chickenpox.
“The vaccine is a live virus that is introducing a very weak form of measles so your body can practice fighting it off,” says Quinones. “This will prepare your immune system to fight against measles if you’re exposed.”
One dosage is typically given during infancy, with a second dosage to follow a few years later. The vaccination is especially important for children because their immune systems are weaker. This is why both doses are recommended before they are in school, where they will be exposed to more children (and more germs).
