Measles FAQ: Your Questions Answered

Measles is a highly contagious viral infection that spreads through the air when an infected person coughs or sneezes. It was declared eliminated in the United States in 2000 thanks to widespread vaccination, but outbreaks still occur, especially in communities with low vaccination rates.

Extremely. Measles is one of the most contagious diseases known. If one person has it, up to 9 out of 10 people nearby who are not immune will also become infected. The virus can hang in the air for up to two hours after an infected person has left a room.

Symptoms show up 7 to 14 days after exposure and include:

• High fever (often over 104°F)
• Cough
• Runny nose
• Red, watery eyes
• Tiny white spots inside the mouth (Koplik spots)
• A red, blotchy rash that starts on the face and spreads to the rest of the body

The rash usually appears 3 to 5 days after the first symptoms. You are contagious from about 4 days before the rash to 4 days after it appears.

Yes. About 1 in 5 unvaccinated people who get measles in the U.S. are hospitalized. Common complications include ear infections, pneumonia, and diarrhea. In rare cases, measles causes brain swelling (encephalitis), which can lead to permanent brain damage. Roughly 1 to 3 out of every 1,000 children who get measles will die from it, according to the CDC.

Yes. While children make up the majority of cases in the current outbreak, unvaccinated or under-vaccinated adults are also at risk.

You are generally considered immune if any of the following apply:

• You were born before 1957. Measles was so widespread before the vaccine that virtually everyone in this age group was exposed and developed natural immunity.
• You have received two doses of the MMR vaccine. This provides about 97% protection.
• You have had a documented case of measles. Prior infection provides lifelong immunity.
• A blood test (titer) shows you have measles antibodies.

Most likely, yes. If you received two doses of the MMR vaccine, you have about 97% protection, and that protection is considered lifelong. If you only received one dose, you have about 93% protection. A second dose is recommended, especially during an active outbreak.

Ask your doctor for a titer test, a simple blood draw that checks for measles antibodies. If the results show you are not immune, get vaccinated. There is no harm in getting an extra dose of MMR even if you were previously vaccinated.

No. If you had a confirmed case of measles, you have lifelong immunity and do not need the vaccine.

Generally, no. The CDC considers people born before 1957 to be immune because measles was so common in that era. However, if a titer test shows you lack antibodies, vaccination is an option. Talk to your doctor.

The MMR vaccine protects against three diseases: measles, mumps, and rubella. It has been used in the United States since 1971 and is one of the most well-studied vaccines in history.

Yes. Hundreds of millions of doses have been given worldwide. The most common side effects are mild: soreness at the injection site, low-grade fever, and a mild rash. Serious side effects are extremely rare. The CDC, the American Academy of Pediatrics, and the World Health Organization all recommend the MMR vaccine.

The standard schedule is:

• First dose: 12 to 15 months of age
• Second dose: 4 to 6 years of age

If you are traveling to an area with an active outbreak, children as young as 6 months can receive an early dose. This dose does not count toward the standard two-dose schedule.

Yes. Any adult who is not immune should get at least one dose. Adults who work in healthcare, travel internationally, or live in outbreak areas should have two documented doses.

No. This claim originated from a 1998 study that was later retracted due to serious ethical violations and data manipulation. The author lost his medical license. Since then, numerous large-scale studies involving millions of children have found no link between the MMR vaccine and autism. The science on this is settled.

For most people, yes. The MMR vaccine is covered by most insurance plans with no out-of-pocket cost. Children can receive free vaccines through the Vaccines for Children (VFC) program. Uninsured adults can find low-cost or free vaccinations at community health centers and local health departments. Visit our clinic finder to locate a provider.

As of February 5, 2026, there are 733 confirmed cases across 20 states. The epicenter is South Carolina, where an outbreak that began in late 2025 has now exceeded 920 total cases, making it the largest single measles outbreak in the U.S. in more than 30 years. In all of 2025, there were 2,276 confirmed cases.

Two factors are driving the surge:

1. Declining vaccination rates. National MMR coverage among kindergartners has dropped from 95.2% in the 2019-2020 school year to 92.5% in 2024-2025. Vaccine exemptions hit a record 3.6% that same year. When coverage drops below 95%, herd immunity breaks down and outbreaks become possible.
2. Global measles activity. Measles cases are increasing worldwide, which means more opportunities for the virus to be brought into the U.S. by travelers.

As of February 5, 2026, 20 states have reported cases: Arizona, California, Florida, Georgia, Idaho, Kentucky, Minnesota, Nebraska, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, South Carolina, South Dakota, Utah, Virginia, Washington, and Wisconsin.

See the full state-by-state breakdown →

1. Call your doctor or local health department immediately. Do not just show up at a clinic or ER. Call first to avoid exposing others.
2. If you are vaccinated with two doses of MMR, your risk is very low.
3. If you are unvaccinated, the MMR vaccine can prevent illness if given within 72 hours of exposure.
4. Monitor for symptoms for 21 days after exposure.
5. If symptoms develop, isolate at home and contact your doctor.

It is possible but uncommon. Two doses of MMR are 97% effective. In the rare case a vaccinated person does get measles, the illness is usually milder.