HOUSTON — Three measles cases have been confirmed in northwest Harris County, two babies and a woman around 30 years of age.

Here's what you need to know about this extremely contagious -- and  sometimes dangerous -- virus:

  1. Measles can be dangerous, especially for babies and young children.  
  2. About 1 out of 4 people who get measles will be hospitalized.  
  3. Measles is highly contagious, and if one person has it, 9 out of 10 people around that person will also become infected if they’re not yet vaccinated.
  4. Measles is an airborne virus that lives in the nose and throat mucus of an infected person. It can spread to others through coughing and sneezing. 
  5. The symptoms of measles generally appear about seven to 14 days after a person is infected, according to the Centers for Disease Control.
  6. Symptoms of measles are a high fever, runny nose, cough, red-watery eyes and sore throat that is followed by a rash breakout 3-5 days after symptoms begin.
  7. The rash usually begins as flat red spots that appear on the face at the hairline and spread downward to the neck, trunk, arms, legs, and feet. Small raised bumps may also appear on top of the flat red spots. When the rash appears, a person’s fever may spike to more than 104° Fahrenheit. 
  8. Some people may suffer from severe -- sometimes deadly -- complications, such as pneumonia (infection of the lungs) and encephalitis (swelling of the brain). 
  9. As many as one out of every 20 children with measles gets pneumonia, the most common cause of death from measles in young children.
  10. The best protection against measles is measles-mumps-rubella (MMR) vaccine. MMR vaccine provides long-lasting protection against all strains of measles. Your child needs two doses of MMR vaccine for best protection:The first dose at 12 through 15 months of age. The second dose 4 through 6 years of age.
  11. If you've had the measles once, you won't get it again.

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