As many countries are experiencing severe and prolonged measles outbreaks, travelers are at increased risk. We asked Dean Blumberg, associate professor and chief of pediatric infectious diseases at UC Davis Children’s Hospital, to answer some frequently asked questions about measles.
Wasn't measles eradicated from the U.S.?
Blumberg: It was eradicated from indigenous transmission in the U.S. in 2000. We don’t have any cases in the U.S. unless they are imported.
How is measles making its return to America?
Blumberg: It is being brought back into the U.S. by travelers from other countries, where the disease is more common, and is being spread to susceptible children. Children may be susceptible to measles because they are too young to be vaccinated, their parents choose not to have them vaccinated, or, in rare instances, when the vaccine does not work.
How is measles spread?
Blumberg: Measles is one of the most contagious diseases out there. Measles can be airborne and can get into very small particle size, be suspended in the air and can stay that way for up to two hours. So, if a person with measles enters and then leaves a room, they can infect people that enter that same room up to two hours later without having direct contact with them. Common symptoms are fever and a rash that starts on a patient’s head and spreads downward. If you suspect that you may have measles, contact your health care provider and ask if you can be seen in isolation.
What are the symptoms of measles?
Blumberg: Measles starts with a fever, which can be very high. Cough, runny nose and red eyes are common. One of the most distinctive features of measles is a red, spotty rash that starts at the head and then spreads downward over the rest of the body. Complications may occur, including diarrhea, which can result in dehydration, ear infections, pneumonia and inflammation of the brain.
How dangerous is measles?
Blumberg: Out of every 1,000 cases, about one to two people die from measles. Before there was a widespread measles vaccination in the U.S., 500 children died from measles every year.
When should children get the measles vaccination?
Blumberg: The first dose of the measles vaccination is typically given between 12 and 15 months of age. The second dose is routinely given between 4 and 6 years of age. By the time children enter school, they should have the two doses. The first dose protects children 95 percent of the time. The second dose increases a child's protection from measles to about 99 percent.
For more information about measles, visit the CDC site.
Does the measles vaccine offer a lifetime of immunity?
Blumberg: The majority of adults are immune since they had measles as children or received the vaccination after it became widely available in 1967. If there are any adults who are uncertain whether they have been vaccinated for measles, I would encourage them to talk to their health care provider and see if there is any vaccination record. If not, they can be vaccinated. If they’ve been vaccinated and are immune, there is no danger in getting an additional dose of vaccine.
What is the MMR vaccine?
Blumberg: MMR vaccine is the combination of three vaccines: measles, mumps and rubella (also known as German measles). These are all live vaccines and are weakened forms of viruses that cause the disease. Most people don’t have any side effects from the shot. However, the side effects that do occur are usually very mild and include low-grade fever, transient rash and mild soreness or swelling where the shot was given, which may cause temporary pain.
Does the MMR vaccine cause autism?
Blumberg: The measles vaccine does not cause autism. There is no link between the MMR shot and autism. Scientists in the United States and many other countries have carefully studied the MMR vaccine, and no association has been found linked to autism. See the UC Davis MIND Institute’s statement on vaccine safety and autism.