Overview
Measles is an infectious disease caused by a virus. It spreads very easily from person to person through the air and can infect people who are not protected. Although many people recover, measles can be serious, especially for young children, pregnant people, and people with weakened immune systems.
Key Symptoms
Symptoms often begin with high fever, cough, runny nose, and red or watery eyes. Small white spots may appear inside the mouth before the rash starts. The rash usually begins on the face and spreads downward to the rest of the body. Some people also feel very tired and unwell.
Causes and Risk Factors
Measles is caused by the measles virus. It spreads when an infected person coughs, sneezes, or breathes out virus-containing droplets and particles that others inhale. The main risk factors are not being vaccinated, close contact with an infected person, travel to areas with outbreaks, and living in crowded conditions. Malnutrition and a weakened immune system can increase the risk of severe illness.
Who Is Affected
Anyone who is not immune can get measles. It is more likely to affect people who have not received measles-containing vaccines or who have not had measles before. Infants too young for routine vaccination, pregnant people, and people with weakened immune systems are at higher risk of complications.
Prevention
Vaccination is the most important way to prevent measles. Public health authorities may also recommend avoiding close contact with infected people, improving ventilation, and following local outbreak guidance. If someone may have been exposed, public health or healthcare professionals can advise on next steps. Keeping sick people away from school, work, childcare, and healthcare waiting rooms unless instructed otherwise can help reduce spread.
Diagnosis and Tests
Healthcare professionals may suspect measles based on symptoms, the rash pattern, exposure history, and vaccination history. Testing may include a laboratory sample such as a throat or nose swab, urine sample, or blood test. Because measles spreads so easily, it is important to call ahead before visiting a clinic or hospital if measles is suspected.
Treatment Categories
Measles is caused by a virus, so care is usually supportive, such as rest, fluids, and monitoring for complications. Some people need hospital care if they become dehydrated, have trouble breathing, or develop other serious problems. Public health teams may also become involved to help limit spread and identify contacts. Treatment plans depend on age, overall health, pregnancy status, and whether complications are present.
When to Seek Medical Care
Seek medical advice promptly if you think you or your child may have measles, especially after exposure to a known case or during an outbreak. Also seek care for signs of dehydration, worsening fever, ear pain, severe cough, or symptoms that are not improving. Call ahead before going in person so staff can help reduce exposure to others.
When It May Be an Emergency
Emergency care may be needed for trouble breathing, severe dehydration, confusion, seizures, extreme drowsiness, or signs that a baby or child is becoming very unwell. Pregnant people and people with weak immune systems should seek urgent advice if measles is suspected. If someone is difficult to wake, has blue lips, or is struggling to breathe, seek emergency help right away.