Measles in 2026: When Babies Get the MMR Vaccine and What to Do

The short answer: the United States has already recorded far more measles cases in 2026 than in all of last year¹. The most effective protection for a child is two doses of the measles, mumps and rubella (MMR) vaccine, on time: one dose is about 93% effective against measles and two doses about 97%². If a baby too young to be vaccinated has been near someone with measles, contact a doctor straight away.

How serious is the 2026 measles outbreak?

Figures updated by the US Centers for Disease Control and Prevention (CDC) on 9 October 2026 show 4,080 confirmed measles cases in the United States as of 8 October, compared with 2,289 for the whole of 2025¹. The key numbers:

95% of cases were in people who were unvaccinated or whose vaccination status was unknown; only 2% had received two doses
96% of cases were linked to outbreaks, with 42 new outbreaks reported during the year
710 cases (17%) were in children under 5, and 15% of those children were hospitalised
10% of all cases were hospitalised

The CDC also notes that MMR coverage among US kindergartners has fallen from 95.2% in the 2019–2020 school year to 92.4% in 2025–2026, while coverage above 95% is needed for community immunity¹. Measles was declared eliminated from the United States in 2000¹.

What are the symptoms of measles?

Timing	What you see
7–14 days after infection	High fever (can rise above 40°C), cough, runny nose, red and watery eyes³
2–3 days later	Tiny white spots may appear inside the mouth³
3–5 days after the first symptoms	A rash starts at the hairline on the face and spreads down to the neck, trunk, arms and legs³

The UK's National Health Service (NHS) adds that the measles rash is not usually itchy, that the spots sometimes join into blotchy patches, and that it can be harder to see on brown and black skin⁴.

Why is measles dangerous for young children?

The CDC is clear that measles is more than a rash, and that it is especially dangerous for babies and young children³:

About 1 in 5 unvaccinated people who get measles is hospitalised
As many as 1 in 20 children with measles gets pneumonia, the most common cause of death from measles in young children
About 1 child in 1,000 develops encephalitis, which can leave a child deaf or with an intellectual disability
Between 1 and 3 of every 1,000 infected children die
Measles can also damage immune cells, leaving a child more vulnerable to other infections for months or even years after recovery

Pregnant women are another high-risk group: measles in pregnancy can lead to premature birth or a low-birth-weight baby³, and the NHS also lists miscarriage and stillbirth⁴.

When is the MMR vaccine given?

Schedules differ between countries:

Where	1st dose	2nd dose
US CDC²	12–15 months	4–6 years
UK NHS⁵	12 months	18 months (children born on or after 1 January 2025 receive MMRV, a four-in-one vaccine that also covers chickenpox)

Follow the schedule where you live, and catch up promptly on any missed dose. For common reactions and catch-up principles, see vaccines explained.

Two further points from the CDC²: the MMR vaccine is not given during pregnancy, and women should avoid becoming pregnant for at least 1 month after having it. It is safe while breastfeeding, and the baby is not affected through breast milk.

How do you protect a baby under 12 months?

Babies this young have not reached the routine vaccination age. The following comes from the CDC²:

Before international travel: infants aged 6–11 months should get 1 dose before the trip. They still need 2 further doses after their first birthday
During a local outbreak: public health authorities may recommend vaccinating infants aged 6–11 months early
After exposure: for someone without immunity, a dose given within 72 hours of exposure may offer some protection or make the illness milder. People at high risk of severe disease may be given immune globulin within 6 days. A doctor decides whether this is needed

The NHS advises seeking urgent medical advice whenever a child under 1 has been in contact with someone who has measles⁴.

When should you get medical help?

If you suspect measles, phone before you go in. Measles spreads very easily to other people in a waiting room⁴.

Get urgent medical advice if⁴:

a baby under 1, a pregnant woman or someone with a weakened immune system has been in contact with measles
breathing is harder than usual
a baby is feeding or drinking much less, or has fewer wet nappies
a high temperature has not come down after fever medicine

Call emergency services for a seizure, severe difficulty breathing, a child who cannot be woken, or sudden confusion⁴.

At home, rest and plenty of fluids help. Keep your child away from nursery or school for at least 4 days after the rash appears, because a person is infectious from around 4 days before the rash until 4 days after⁴. For managing a temperature, see our fever care guide.

Frequently asked questions

Can you still catch measles after two doses? A few people do. Among US cases in 2026, 2% had received two doses¹. The CDC explains that some people's immune systems may not respond as well to the vaccine, or that protection may decrease over time².

My child has a rash. Is it measles? Not necessarily. The NHS says measles is unlikely in anyone who has had both vaccine doses or has had measles before⁴. To tell common rashes apart, see our guide to rashes in babies and toddlers.

Does the MMR vaccine cause autism? No. The CDC states that scientists in the United States and other countries have studied the MMR vaccine carefully and none has found a link with autism².

This article summarises public information from the US CDC and the UK NHS. Case numbers are as of 8 October 2026 and will keep changing. Vaccination schedules vary by country, so follow the advice of your local health authority and your doctor. If your child shows any of the warning signs above, seek medical care immediately.

References

Centers for Disease Control and Prevention. (2026, October 9). Measles cases and outbreaks. https://www.cdc.gov/measles/data-research/index.html ↩ ↩² ↩³ ↩⁴ ↩⁵
Centers for Disease Control and Prevention. (2026, April 29). Measles vaccination. https://www.cdc.gov/measles/vaccines/index.html ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶
Centers for Disease Control and Prevention. (2026, August 5). Measles symptoms and complications. https://www.cdc.gov/measles/signs-symptoms/index.html ↩ ↩² ↩³ ↩⁴ ↩⁵
NHS. (2025, July 31). Measles. https://www.nhs.uk/conditions/measles/ ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸
NHS. (2025, December 23). MMRV (measles, mumps, rubella and chickenpox) vaccine. https://www.nhs.uk/vaccinations/mmrv-vaccine/ ↩