Measles

One of the most infectious diseases known. It is back in the UK because vaccination coverage fell.

What it is

Measles is among the most contagious infections there is. One person infects around 15 others in an unprotected population, and the virus stays airborne in a room for up to two hours after the infected person has left.

The UK lost its measles elimination status in 2019, and outbreaks have followed. The reason is straightforward: MMR coverage fell below the 95% needed for herd immunity, and in some areas is well below it.

Measles is not a mild childhood illness. Around 1 in 5 cases needs hospital treatment. It causes pneumonia and encephalitis, and it causes death.

It also erases immune memory, so children are more vulnerable to other infections for years afterwards. That effect is called immune amnesia and it is not widely known.

Two doses of MMR give around 99% protection.

Signs you might notice

First, several days of high fever, cough, runny nose and red sore eyes. People think it is a cold.

Koplik spots: tiny white spots inside the cheeks, which appear before the rash and are diagnostic.

Then a blotchy red-brown rash starting behind the ears and on the face, spreading down the body. On darker skin it may be harder to see and easier to feel.

Complications: ear infection, pneumonia, seizures, encephalitis.

Very serious signs: drowsiness, seizures, severe breathlessness, or confusion.

How it can affect day-to-day life

Highly vulnerable people cannot be vaccinated: babies under one, and people who are immunosuppressed by cancer treatment or medication. They depend on everybody else's vaccination.

If you suspect measles, phone ahead rather than sitting in a waiting room. This is one of the few infections where turning up unannounced causes real harm to other patients.

Exclusion is four days from the rash appearing, and contacts who are not immune may need urgent advice.

Supporting someone well

Get both MMR doses, and catch up at any age if they were missed. It is free on the NHS for anybody, adults included.

Phone ahead before attending a GP surgery or hospital with suspected measles.

Keep the person away from anybody pregnant, any baby under one, and anybody immunosuppressed.

Rest, fluids and paracetamol; there is no specific antiviral treatment.

Seek urgent help for breathlessness, drowsiness, seizures or dehydration.

Report suspected cases; measles is notifiable, and public health need to know to protect contacts.

Where to get help

Call 111 or a GP for advice, and say you suspect measles before attending.

Contact a GP practice to arrange catch-up MMR at any age.

Drowsiness, seizures, severe breathlessness or confusion is a 999 call.