A childhood illness that causes fever and a widespread nonitchy rash

  • Mainly affects unimmunized children between the ages of 1 and 5
  • Gender, genetics, and lifestyle are not significant factors

Measles is a highly contagious viral illness that causes a distinctive rash and fever and mainly affects young children. Rare in the developed world because of routine immunization, the disease kills up to a million unimmunized children in the developing world each year.

The measles virus is easily transmitted in minute airborne droplets from the coughs and sneezes of infected people. A child who has measles may feel very ill, and there is a small risk of complications, especially if the child has reduced immunity or is severely malnourished. Measles is contagious for 1–2 days before the rash appears and for about 5 days afterwards.

What are the symptoms?

Symptoms of measles usually develop 10 days after infection and may include:

  • Fever.

  • Tiny white spots with a red base, known as Koplik spots, on the insides of the cheeks.

  • After 2–4 days, a red, nonitchy rash that starts on the head and spreads downwards. At first, the rash consists of separate flat spots. The spots then merge to give a blotchy appearance.

  • Painful, red, watery eyes (see Conjunctivitis).

  • Stuffy or runny nose.

  • Hacking cough.

The most common complications of measles are bacterial infections of the middle ear (see Acute otitis media in children) and the lungs (see Pneumonia). In about 1 in 1,000 cases, the brain is affected (see Viral encephalitis), a serious complication that starts 7–10 days after the appearance of the rash.

What might be done?

Your doctor will probably be able to diagnose measles from the combination of symptoms. In most children, rest and simple measures to reduce a fever (see Bringing down a fever) are all that are needed for a full recovery. If there are no complications, symptoms usually disappear in 7 days. Antibiotics may be prescribed if a bacterial infection develops as a complication of measles, such as pneumonia.

Koplik spots in measles

These tiny white spots may appear on the insides of the cheeks when the symptoms of measles first develop, shortly before the onset of the rash on the head and body.

Can it be prevented?

Babies are immunized against measles with a measles, mumps, and rubella (MMR) vaccine, given at 12–15 months and again between 3 and 5 years (see Routine immunizations). Immunization or an attack of measles usually gives lifelong immunity to the disease.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

Back to top