Health officials in two US states are tracking measles outbreaks as cases rise to nearly 100 people. The Texas Department of State Health Services reported Friday that it was aware of 90 cases diagnosed in the last month in the South Plains area,

According to the CDC, if you were born after 1957, one dose is considered sufficient to be considered protected from measles. Some adults may need a second dose. The CDC says adults who are going to be in high-risk settings for transmission should make sure they’ve had two doses at least 28 days apart.

Texas' measles outbreak is up to 90 cases. Here's what you need to know about the virus, vaccination and boosters.