What is measles?

Measles is a highly contagious viral disease that at one time affected nearly everyone before the age of 20 years. But with the development of a vaccine and widespread immunization, measles has become a very rare disease in the United States.

Although measles remains relatively rare in this country, there have been recent outbreaks all over the United States. These cases are occurring in children and adults who have not been vaccinated or have been incompletely vaccinated against measles.

The main reason for the increase in the number of cases of measles is that some parents are concerned that the measles vaccine – usually combined with the mumps and rubella (MMR) vaccine– may cause autism. Large studies have shown no connection between the MMR vaccine and autism, and the risks and complications associated with contracting measles can be very serious. The MMR vaccine has been shown to be extremely safe and not at all associated with autism.

What causes measles, and how is it spread?

Measles is caused by a virus that is spread by contact with droplets from the nose, mouth, or throat of an infected person. Symptoms of measles usually do not appear until 8-12 days after coming into contact with the virus.

What are the symptoms of measles?

The most common symptoms associated with measles include high fever, a barky cough, red or bloodshot eyes, runny nose, followed by a red rash, which starts at the head and then spreads downward. Other symptoms of measles include:

  • Sore throat
  • High fever
  • Muscle pain
  • Sensitivity to light

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