Measles

Overview

By Tina Shahian, PhD

Measles, also known as rubeola, is a serious childhood disease that is caused by a highly contagious virus. The common symptoms of measles include a high fever, cough, runny nose, red watery eyes and a signature red body rash. There is no cure for measles and most people successfully clear the disease over the course of a few weeks. Measles rash after 3 days of infection (source: CDC)Children younger than age 5 and adults older than age 20 are at increased risk of developing serious measles-associated complications, including pneumonia and encephalitis (swelling of the brain).

Complications of Measles

  • Ear infection: affects 10% of children with measles and can cause hearing loss
  • Diarrhea: occurs in less than 10% of patients with measles and can be severe
  • Bronchitis/laryngitis/croup: an inflammation of the voice box (larynx) and airways
  • Low platelets: a drop in the blood cells involved in clotting is seen in some patients
  • Pregnancy: measles can cause loss of pregnancy or premature birth
  • Pneumonia: affects 1 in 20 children with measles and is the common cause of death in this group
  • Encephalitis: affects 1 in 1000 children with measles and can lead to swelling of the brain tissues, vomiting, convolutions, permanent intellectual disability and death
  • Subacute sclerosing panencephalitis (SSPE): A rare and deadly disease of the central nervous system that can affect patients up to a decade after they develop measles.

Prior to 1963 when the measles vaccine was developed, measles affected most children before they reached the age of 15. At the time, there were a total of 3-4 million infections per year in the United States, resulting in up to 500 deaths annually. Following widespread vaccination in the 1980s, the rate of new measles infections dropped by 80%, followed by an additional decline once the two-dose recommendation for the vaccine was implemented in 1989. Currently, there are an average of 60 reported measles infections in the United States each year. Despite the fact that the majority of children worldwide are now receiving the measles vaccine, the disease continues to be a leading cause of death in small children. In 2013, there were a reported 145,700 global deaths due to measles, the majority of which were in developing countries.

Causes and Risk Factors

The measles virus is present in the nose and throat of an infected person. It spreads through sneezing, coughing, talking and other activities that cause infected droplets from these cavities to become airborne. A person becomes infected by directly inhaling the infected droplets, which remain infectious for several hours. Alternatively, the hands can pick up the live virus from an infected surface and transmit them via contact with the eyes, nose and mouth. The measles virus is extremely contagious; 90% of those who come in close proximity to an infected person are expected to become infected. A person with measles can transmit the virus starting at four days before the rash develops, until four days after the rash has begun.

Unvaccinated children under the age of 5 are at highest risk for measles and its potentially fatal complications. The known risk factors for measles are:

  • Lack of immunity: Newborns and young children who are not vaccinated against measles are at highest risk of being infected. Children and adults who are vaccinated but do not develop immunity are also susceptible. The risk is especially high in developing countries due to poor access to vaccines.
  • International travel: Unvaccinated individuals can become infected by travelling to developing countries where measles is more prevalent.
  • Pregnancy: Pregnant women who are not vaccinated can become infected with potentially fatal consequences to the fetus.
  • Vitamin A deficiency: Deficiency in vitamin A increases the chances of contracting measles.

Symptoms

The symptoms of measles appear after a 10-14 day incubation period, during which time no symptoms are present. The initial stage of measles begins with a high fever that can last up to a week, followed by cough, runny nose, red/watery eyes and white spots inside the mouth. After 3-5 days, the second stage begins with a red rash that starts on the face and neck and spreads over the rest of the body. The rash looks like small raised red bumps and generally lasts about a week before gradually fading. The full list of symptoms includes:

  • High fever
  • Cough and sore throat
  • Runny nose
  • Red watery eyes (conjunctivitis)
  • Tiny white spot inside the mouth
  • Red body rash that coincides with a spike in fever (104° Fahrenheit).

Diagnosis and Treatment

Measles is diagnosed by its signature rash, as well as the white spots inside the mouth. If needed, laboratory test are also available to identify the measles virus. There is no cure or specific treatment for measles. However, there are ways to manage the risks of developing serious complications.

  • Post-exposure vaccine: Receiving the measles vaccine 72 hours after exposure to the virus may help in prevention, or lead to a milder form of the disease.
  • Immune serum globulin: Injection of antibodies in pregnant women, infants or those with weakened immunity may help prevent measles, or lessen disease severity.
  • Fever reducer: Over-the-counter fever reducers can be used to manage fever symptoms in children.
  • Antibiotics: Antibiotics are prescribed to treat secondary bacterial infections like pneumonia or an ear infection.
  • Vitamin A supplement: Vitamin A supplementation can help reduce measles symptoms and deaths in patients with nutritional deficiency.

Prevention

The recommended course of the measles vaccine is the best line of defense against the disease. The vaccine, which is called the MMR vaccine, combines three diseases (measles, mumps, and rubella) and is administered in two doses during childhood. Anyone who develops measles must remain in isolation in order the prevent transmission to high-risk populations, such as infants, pregnant women and those with weakened immunity.

Sources

  • “Measles (Rubeola)”. Centers for Disease Control and prevention (CDC). Retrieved Oct. 26, 2015. http://www.cdc.gov/measles/index.html.
  • "Measles". Mayo Clinic. Retrieved Oct. 26, 2015. http://www.mayoclinic.org/diseases-conditions/measles/basics/definition/con-20019675.
  • “Measles”. World Health Organization (WHO). Retrieved Oct. 26, 2015. http://www.who.int/mediacentre/factsheets/fs286/en/.