What Is Measles?
Measles is a highly contagious viral infection. It is caused by the measles virus.
The virus is spread by direct contact with nasal or throat secretions of an infected person. Less commonly, it can be spread by droplets in the air. It is typically spread in winter and spring. Measles is contagious:
- 1-2 days before the onset of symptoms
- 3-5 days before the rash
- 4 days after the appearance of the rash
Symptoms include:
- Fever (often high)
- Runny nose
- Red eyes
- Cough
- A unique rash
Symptoms usually begin within 8-12 days after exposure. The rash lasts about 4-6 days. Full recovery can take 7-10 days. In severe cases (or in people with immune disorders), serious brain infection or pneumonia can happen when recovering. Permanent brain damage and death are very rare in the developed world.
Measles was once a common childhood illness. Now, there are fewer cases of measles in the United States. This is due to the measles vaccine. But, there have been outbreaks in recent years.
You are very unlikely to get measles if you were immunized as a child. However, unvaccinated or inadequately vaccinated people are at increased risk if they:
- Live in crowded and/or unsanitary conditions
- Travel to less developed countries where measles is common
- Have a weakened immune system (eg, HIV ), even if previously vaccinated
- Were born after 1956 and were never diagnosed with measles
- Have only received an inactivated or killed vaccine prior to 1968 (Today's live vaccines are much more effective.)
Measles is caused by a virus. It cannot be treated with antibiotics. Efforts are focused on relieving the symptoms, such as:
- Gargling with warm salt water
- Using a cool-mist humidifier
- Lukewarm sponge baths
- Plenty of fluids and fever-reducing medicines (that do not contain aspirin)— Note : Aspirin should never be used in children and teens who have a current or recent viral infection.
- Vitamin A —This may be helpful for people who are deficient in vitamin A.
What Is the Measles Vaccine?
The measles vaccine consists of live measles viruses made in chicken embryo cells. The viruses found in the vaccine have been made harmless during the manufacturing process.
It is normally given in combination with:
The vaccine is given under the skin.
Who Should Get Vaccinated and When?
All children (with few exceptions) should receive the vaccine two times:
- 12-15 months
- 4-6 years (school entry)—can be given earlier, but the two doses must be separated by at least four weeks
The vaccine can also be given to infants aged 6-11 months who will be traveling internationally. These infants should also get the two routine shots at ages 12-15 months and 4-6 years.
For those 18 years of age or younger who have not been vaccinated, two doses of MMR are given. The doses are separated by four weeks.
Adults born after 1957 who have not been previously vaccinated may need 1-2 doses. Talk with your doctor if you were not previously vaccinated.
What Are the Risks Associated With the Measles Vaccine?
The majority of people who get the vaccine do not have any side effects. The most common side effects are a fever and a rash. Redness and swelling at the injection site may occur. Rare complications include:
- Anaphylaxis —severe, life-threatening allergic reaction
- Temporary thrombocytopenia—low platelet count which can cause bleeding
- Seizures—in children inclined to have febrile seizures (convulsion during high fevers)
Who Should Not Get Vaccinated?
In some cases, the vaccine should be delayed, such as:
- Children who are sick with a fever—The vaccine can be given if you have a minor illness.
- Recent immunoglobulin (eg, antibody) or corticosteroids therapy
Most children and teens should receive their vaccinations on schedule. However, certain groups should not be vaccinated:
- People with immune system disorders (eg, AIDS )—If you have HIV and are doing well, you should consider getting the vaccine. Measles can be fatal if you have HIV.
- Pregnant women—Avoid becoming pregnant for at least one month after getting the vaccine.
- Previous severe allergic reaction to the vaccine or its components
- Previous thrombocytopenia clearly related to the vaccine
People who meet one of the following criteria for measles immunity do not need to be vaccinated:
- Documentation of two live weakened measles vaccines after their first birthday and spaced at least four weeks apart
- Documentation of doctor-diagnosed measles
- Blood test that shows immunity to measles
- Born before 1957
What Other Ways Can Measles Be Prevented Besides Vaccination?
If you have the measles, you should be isolated to stop the virus from spreading. For example, children with the measles should stay home until the virus is over.
The immunoglobulin (IG) shot can be given to people who have been exposed to the virus and are not vaccinated. The shot contains antibodies against the virus. If it is within six days of exposure, the shot can protect you. IG is especially important for:
- Children aged less than one year old
- Pregnant women
- People who have an immune system disorder
IG is not for those who have received at least one vaccination after 12 months of age unless they have an immune system disorder.