Measles is a highly contagious viral infection that causes various cold-like symptoms and a characteristic rash.
Measles is caused by a virus.
Symptoms include fever, runny nose, hacking cough, red eyes, and a red itchy rash.
The diagnosis is based on typical symptoms and the characteristic rash.
Treatment is aimed at relieving symptoms.
Although the majority of children recover, measles can be fatal or lead to brain damage.
Routine vaccination can prevent the infection.
Before measles vaccination became widely available, measles epidemics occurred every 2 or 3 years, particularly in preschool-aged and school-aged children. Small, localized outbreaks occurred during the other years.
Measles is still common in some countries. Worldwide, each year, measles infects about 10 million people and causes about 134,000 deaths, primarily in children.
In the United States, measles is uncommon because of routine childhood vaccination. From 2000 to 2010, an average of only 63 cases per year were reported to the Centers for Disease Control and Prevention (CDC). However, in 2019, 1,274 cases of measles were reported to the CDC. That was the highest number reported since 1992. That increase was mostly caused by unvaccinated people who became infected in countries where measles is more common and then traveled to the United States.
In 2020, only 13 measles cases were reported in the United States amid the COVID-19 global pandemic. In 2022, 121 cases were reported.
Measles infection is more likely to spread in communities where many people live closely together, such as college campuses or other close-knit communities. Lack of routine childhood vaccination also contributes to the increase in diseases that could be prevented by vaccines.
A woman who has had measles or has been vaccinated passes immunity (in the form of antibodies) to her child. This immunity lasts for most of the first year of life. Thereafter, however, susceptibility to measles is high unless vaccination is given. A person who has had measles develops immunity and typically cannot contract it again.
People become infected with measles by breathing in small airborne droplets of moisture coughed out by an infected person. Most people who are not immune to measles develop the infection after they are exposed to a person with measles. Measles is contagious from 4 days before until 4 days after the rash appears.
Symptoms of Measles
Measles symptoms begin about 7 to 14 days after infection. The infected child first develops a fever, runny nose, hacking cough, and red eyes. Sometimes the eyes are sensitive to bright light. Before the rash begins, tiny, bright red spots with white or bluish white centers (Koplik spots) may appear inside the mouth. These white or bluish white centers may resemble grains of sand. Then the child develops a sore throat.
A mildly itchy rash appears 3 to 5 days after the start of symptoms. The rash begins on the face in front of and below the ears and on the side of the neck and looks like irregular, flat, red areas that soon become raised. The rash spreads within 1 to 2 days to the trunk, arms, palms, legs, and soles and then begins to fade on the face.
At the peak of the illness, the child feels very sick and develops eye inflammation (conjunctivitis), the rash is extensive, and the temperature may exceed 104° F (40° C). In 3 to 5 days, the temperature falls, the child begins to feel better, and any remaining rash quickly fades. The rash turns a brownish color, and then the skin peels.
Complications of measles
Brain infection (see encephalitis) occurs in about 1 out of 1,000 children with measles. If encephalitis occurs, it often starts with a high fever, headache, seizures, and coma, usually 2 days to 2 weeks after the rash appears. The illness may be brief, with recovery in about 1 week, or it may be prolonged, resulting in brain damage or death.
Pneumonia caused by measles infection of the lungs occurs in about 5% of people. In fatal cases of measles in infants, pneumonia is often the cause of death.
Excessive bleeding may occur after the measles infection resolves because the person's blood platelet levels become low (thrombocytopenia). People usually have bruising of the skin and mild bleeding, but occasionally bleeding is severe.
Temporary liver inflammation (hepatitis) and diarrhea may occur during an infection.
Subacute sclerosing panencephalitis is a rare complication of measles that causes brain damage and death often over years of progressive brain deterioration.
Diagnosis of Measles
A doctor's evaluation
The diagnosis of measles is based on the typical cold-like symptoms, Koplik spots, and characteristic rash.
Blood tests to identify the virus are done mainly to document cases for public health purposes so that health officials can try to contain outbreaks and limit further spread.
Treatment of Measles
Vitamin A
Drugs to reduce fever
Infected people who are hospitalized should be placed in special hospital rooms and isolated from others during their illness. Infected people who are not hospitalized should severely limit contact with others during their illness.
vitamin A has been shown to reduce the number of deaths and serious disease resulting from measles in countries where is common.
Children with measles are kept warm and comfortable.
Prognosis for Measles
In healthy, well-nourished children, measles is usually not serious. However, in the United States, about 1 to 2 of 1,000 children infected with measles die. This number of children is much higher in medically underserved countries. Undernutrition and may increase the risk of death in people infected with measles.
Worldwide, approximately 134,000 people die each year of measles, typically from complications of pneumonia or encephalitis.
Prevention of Measles
MMR vaccine
Prevention before exposure
Measles vaccine is given as part of the combined measles-mumps-rubella (MMR) vaccine, which contains live but weakened measles, mumps, and rubella viruses. The MMR vaccine is one of the routine immunizations of childhood and is given to children in most nations that have a robust health care system. The MMR vaccine and the varicella (chickenpox) vaccine are also available as a combined vaccine (MMRV vaccine).
The MMR vaccine generally provides lasting immunity and has decreased cases of measles in the United States by 99%.
Two doses of MMR vaccine are routinely recommended. The first dose is given between 12 and 15 months of age but can be given to children as young as 6 months during a measles outbreak or before international travel. The second dose is given between 4 years and 6 years of age.
Children who were less than 1 year of age when immunized still need 2 more doses after their first birthday.
In some people, the vaccine causes mild fever and a rash, but people are not contagious. The MMR vaccine does not cause autism (see MMR vaccine and concerns about autism).
MMR is a live vaccine and is not given during pregnancy.
For more information about who should and who should not receive the MMR vaccine, see Administration of MMR Vaccine. See also Side Effects of MMR Vaccine.
Preventive treatment after exposure
Children (and adults) who are exposed to measles and who do not have immunity may be given the vaccine within 3 days of exposure and may then be protected.
People who should not receive the MMR vaccine, such as pregnant women and people with a severely weakened immune system, may be protected if they receive an injection of immune globulin within 6 days of exposure. People who receive immune globulin can be given the MMR vaccine 5 to 6 months later if possible.
