If you’re planning to travel this summer, make sure you’re vaccinated against measles.

The CDC is changing their guidelines for U.S. travelers heading abroad when it comes to being vaccinated against the disease. Up until last week, the vaccine was only recommended for kids. That’s now expanded to all travelers due to the spread of measles both at home and abroad.

Dr. Gretchen Newman, an infectious disease specialist with Detroit Medical Center, says the measles vaccine is safe and highly effective.

“Vaccines are incredibly highly tested,” Newman said. “They are incredibly tightly scrutinized. The data that goes in and the science that goes into producing a new vaccine and bringing a new vaccine to market is really designed with that cost benefit in mind, remembering that we are giving vaccines to healthy people. So our tolerance for risk is much, much, much less.”

The recommendations now also include infants 6 to 11 months old. Everyone should get one dose at least two weeks before traveling.