As of May 2025, measles outbreaks have been confirmed in 31 jurisdictions of the U.S., with most cases linked to low vaccination rates. The Centers for Disease Control and Prevention (CDC) is urging healthcare providers to talk with travelers about vaccination. Health experts warn that if vaccination rates keep going down, measles could become common again in the U.S., leading to millions of cases over the next 25 years.

While the overall risk is low, measles remains highly contagious. People living with lupus may be more vulnerable if their immune system is suppressed, either by the disease itself or by medications such as corticosteroids or biologics. Although the measles, mumps, rubella (MMR) vaccine is highly effective, immunity can wane over time, which means even previously vaccinated adults may still be at risk.

What Is Measles?

Measles is a very contagious virus. It spreads through the air when someone who is sick coughs, sneezes, or talks, and it can stay in the air for up to two hours after they leave. If you’re exposed to the measles virus and not protected, there’s about a 90 percent chance you’ll get sick.

Symptoms usually begin 10 to 14 days after exposure. Early signs include fever, cough, runny nose, and red, watery eyes. Small white spots may also appear inside the mouth. A few days later, a rash spreads from the face down to the rest of the body. This rash appears red on light skin tones and purple or brown on darker skin tones.

Most people recover in a few weeks, but measles can cause serious complications such as pneumonia, severe diarrhea, and, in rare cases, encephalitis (brain swelling). These risks are higher among babies, older adults, pregnant people, and those with weakened immune systems, including people taking immunosuppressive medication for lupus.

Who’s at Risk for Getting Measles?

People at risk include:

• Those who are unvaccinated or have only had one dose of the MMR vaccine
• Adults who don’t know their vaccination history or were vaccinated before 1968, when less-effective vaccines were used
• Travelers, especially those visiting countries with measles outbreaks or regions in the U.S. where vaccination rates are low
• People living in communities where measles is spreading
• Pregnant individuals, who face a higher risk of complications like preterm birth or fetal loss
• Babies under 1 year old, who are too young to be fully vaccinated
• People in close-contact settings, like schools or shelters, where the virus can spread quickly
• People with weakened immune systems due to conditions like lupus or from medications used to treat it

Also, a recent study found that measles could come back and spread more easily across the U.S. if fewer people get vaccinated, especially in areas where many people are not protected.

How Effective Are MMR Vaccines in Preventing Measles?

The measles vaccine is highly effective. After two doses, about 99 percent of people develop lasting immunity. The first dose protects most people, and the second dose helps those who didn’t respond the first time.

Most people remain protected for life. However, rare cases of measles can still occur in vaccinated individuals, especially if their immune system was weak when they got the vaccine, or if their immunity has waned over time.

This is why people with lupus or others taking immune-suppressing medication should talk to their doctor about whether they need testing or revaccination.

What Are the Risks of Getting an MMR Vaccine?

As with any vaccine, side effects can happen. Common side effects include:

• Mild fever
• Rash
• Temporary swelling of lymph nodes

Some adults may also experience joint pain or minor allergic reactions. Serious side effects are rare. Also, multiple studies have found no link between the MMR vaccine and autism.

Talk to your healthcare provider to confirm whether the vaccine is safe and necessary for you.

Are MMR Vaccines Safe for People With Lupus?

Live-virus vaccines like MMR are generally not recommended for people with lupus who are taking immunosuppressive therapy. According to the Lupus Research Alliance, “Vaccines with live viruses are generally not recommended for people with lupus.”

However, if your lupus is stable and you’re not currently taking medications that weaken your immune system, your doctor may test your immunity or consider the vaccine as appropriate.

Timing and medication status matter. For example, the 2022 American College of Rheumatology guidelines note that live vaccines might be considered only in carefully selected cases and that inactivated vaccines are preferred whenever available.

How Can You Tell if You Need an MMR Vaccination or Booster?

Everyone’s health situation is unique. Talk with your doctor to understand your needs. Depending on your history and current health, they may recommend:

• A blood test to check your immunity
• A booster shot if your immunity has faded
• Delaying vaccination and taking other precautions if you’re taking immunosuppressive therapy for lupus

How Else Can You Protect Yourself and Others From Measles?

The CDC recommends additional precautions:

• Practice good hygiene — Wash hands frequently, avoid touching your face, and clean shared surfaces.
• Be mindful of travel — Before traveling internationally, confirm your vaccine status.
• Limit exposure during outbreaks — Avoid crowded indoor spaces in communities with low vaccination rates.

What Should You Do if You’ve Been Exposed to Measles?

If you’ve been exposed to measles and aren’t vaccinated:

• Getting an MMR vaccine within 72 hours can prevent or reduce illness severity if your immune system is strong enough.
• If you’re taking medications for lupus that suppress the immune system, your doctor may recommend immune globulin (IG) within six days instead.

Check with your doctor to see if you are eligible for any of the above, if you’ve been exposed to measles and aren’t immune.

Stay Protected, Stay Connected

On MyLupusTeam, the social network for people with lupus and their loved ones, thousands of individuals come together to ask questions, give advice, and share their stories.

Have you talked to your doctor about your measles immunity or vaccination status? How do you stay informed and prepared during outbreaks like this? Share your experiences in the comments below, or start a conversation on your Activities page.