Most of the people who got measles had not been vaccinated, the CDC said.
Measles is common in Europe, Asia, the Pacific and Africa, officials say, and travelers with measles can spread the disease to people in the US who have not been vaccinated.
107 cases in 21 states have been reported already this year, including four in MI.
Last year, there were 118 measles cases in 15 states and Washington, D.C. The last outbreak happened in 2015 when 188 people were infected. The total number of cases that year is the highest number since measles elimination was declared in the USA in 2000. Of those, 338 were connected to a single large outbreak.
What should you know about measles?
The CDC says the measles virus is "highly contagious" and can be spread to others by coughing or sneezing. Symptoms show up in 10 to 14 days after exposure.
Platt said the first sign of measles is a giant red rash. Within about 5 days, it fades in the order it appeared.
According to the CDC, some people may suffer from severe complications, such as pneumonia and brain swelling which could result in hospitalization or death.
It causes fever, dry coughs, sore throats, and a skin rash.
What is the treatment for measles?
If you think your child has the measles, keep them home from school and contact your doctor immediately.
"Two doses of MMR vaccine are 97% effective against measles and 88% effective against mumps", the CDC says.
Anna Chacon is a dermatologist and part of the ABC News medical unit.