Measles is a virus that causes fever and a rash, and it can cause serious health complications. It is highly contagious and anyone who is not vaccinated against the virus can get it at any age.
Measles is still common outside of the U.S. and is sometimes brought into the country by visitors or returning travelers. Usually individual cases do not result in outbreaks due to overall high vaccination rates, but in neighborhoods with low vaccination rates, an exposure can lead to spread.
Measles is very contagious. If one person has measles, up to 90% of people around them will also get it if they are unvaccinated or otherwise not immune.
The measles virus lives in an infected person’s nose and throat mucus. Measles spreads through the air when someone with measles sneezes or coughs. The virus can stay in the air for up to two hours. This means people get measles just by being in a room where a person with measles has been, even after that person has left the room.
People can also get measles by touching a surface that has the virus on it and then touching their eyes, nose, or mouth. A person can be contagious from four days before through four days after the rash appears.
Vaccination is the best way to prevent measles. In the U.S., the measles vaccine is combined with mumps and rubella vaccines into one vaccine called measles, mumps, and rubella (MMR). The MMR vaccine is safe and effective. One dose of the MMR vaccine is 93% effective against measles and two doses is 97% effective against measles. The MMR vaccine provides long-term protection from measles.
Most pediatricians offer MMR vaccine. For help finding a vaccination site:
MMR for children: Children should get an MMR vaccine at 12 months. A second dose of the MMR vaccine should be given at 4 years of age. MMR vaccination is required for childcare and school entry in New York.
MMR for adults: Adults born before 1957 (before a measles vaccine was available) are very likely to have had measles and are considered immune to measles. For most adults born on or after 1957, one MMR dose is considered sufficient. There are some adults who are recommended to get a second dose, including healthcare workers, students at post-high school educational institutions, and international travelers. There is no recommendation for a third dose of MMR for measles protection, regardless of how long it has been since the last dose.
If you do not have written documentation of measles immunity, you should get vaccinated. There is no harm in getting a dose of MMR vaccine if you may already be immune to measles (or mumps or rubella).
A small percent of adults born between 1957 to 1968 received inactivated MMR vaccine, which was discontinued because it was found to be less effective than the MMR vaccine used today. Adults born between 1957 to 1968 are recommended to be revaccinated if they received the inactivated measles vaccine or if they don’t know which type of measles vaccine they received.
All people traveling internationally should ensure they are vaccinated and have the recommended doses of MMR vaccine.
There are usually no special travel vaccine recommendations for domestic travel within the U.S. However, on rare occasions, due to a significant outbreak, the health department where the outbreak is occurring might have additional travel recommendations for residents and visitors to the area where an outbreak is occurring
Most people who receive the MMR vaccine do not have any side effects. Some people experience mild side effects, such as fever, mild rash or swelling. Severe problems are very rare. The current measles vaccine has been used safely for decades, keeping children healthy and saving many thousands of lives in the U.S.
Because of widespread vaccination, cases of measles have decreased more than 99%. Before the measles vaccine was available, an estimated 3 million to 4 million people got measles and 500 people died each year in the U.S.
Vaccine ingredients do not cause autism. More than 25 articles have been published since 1999 that have found no link between vaccines and autism, as well as no link between the MMR vaccine and autism in children. Sources claiming otherwise are not based in science.
Symptoms usually start seven to 14 days after exposure to the virus. In some cases, symptoms may start as late as 21 days after exposure.
Early symptoms include:
Three to five days after initial symptoms, a rash of red spots appears on the face and then spreads over the entire body.
Anyone can become infected with measles, but the virus is more severe in infants, pregnant people and people with a weakened immune system (such as from cancer treatment or HIV). Complications of measles include:
About one in five people who get measles in the U.S. will be hospitalized. About one of every 1,000 people will develop encephalitis (brain inflammation), which can lead to brain damage. And even with the best care, one or two out of 1,000 people with measles will die. In rare cases, several years after having had measles, people develop a complication called subacute sclerosing panencephalitis (SSPE), a fatal disease of the central nervous system.
There is no specific medicine for measles, but there are medicines that can reduce symptoms, such as fever. People with complications may need treatment specific to their health problem.
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