PHOENIX - State health officials are watching 20 people who were likely exposed to measles since the outbreak began nearly two weeks ago.
The Arizona Department of Health Services says the 11 confirmed cases will almost certainly go up, as more time passes since the initial case.
State health officials say the number of exposed people could reach into the thousands.
Right now is the time to act, they say.
People who chose not to get vaccinated or have children who are older than six months and are not vaccinated, now is the time to get the shot. Measles can be deadly and it’s highly contagious.
"Anytime we see measles cases in this state, we are very alarmed, just because the disease is so contagious,” said Jessica Rigler from the Arizona Department of Health Services.
“If you are vaccinated, that's great news," she said. "Most people are vaccinated and that helps protect them from measles."
Officials are warning health care providers, like doctors and hospitals, of the current outbreak.
If you think you were exposed and you are not vaccinated, call your doctor. Do not go straight to a medical facility for treatment, because the risk of exposing others is extremely high.
See a map of the exposure locations and a full list below.
List of public exposure areas:
Wednesday, May 18: Denny's (1851 E. Florence Blvd., Casa Grande) from 2 p.m. - 5:30 p.m.
Wednesday, May 18: Wal-Mart Pharmacy (1741 E. Florence Blvd., Casa Grande) from 3:30 p.m. - 6:30 p.m.
Thursday, May 19: Wal-Mart Pharmacy (1741 E. Florence Blvd., Casa Grande) from 5 p.m. - 8 p.m.
May 20 through May 29: Circle K (2382 N. Pinal Ave., Casa Grande)
Friday, May 20: Safeway (1449 N. Arizona Blvd., Coolidge) from 4 p.m. - 7 p.m.; Golden Corral (2064 E. Florence Blvd., Casa Grande) from 8 p.m. - 11 p.m.; Ross (1004 N. Promenade Pkwy, Casa Grande) 9 p.m. - 12 a.m.; Wal-Mart (1741 E. Florence Blvd., Casa Grande) 10 p.m. - 1 a.m.; Corner Store (2182 E. Florence Blvd., Casa Grande) from 10 p.m. - 1 a.m.
Friday, May 27: Cheddars (2530 W. Chandler Blvd., Chandler) from 5 p.m. - 9 p.m.
Saturday, May 21: Harrah's Ak-Chin Casino (15406 N. Maricopa Rd.) from 6 a.m. - 2 a.m. on May 22.
Sunday, May 22: Arco AM/PM (2245 E. Florence Blvd., Casa Grande) from 8:30 a.m. - 11 a.m.
Sunday, May 15 1 p.m. - 3 p.m.; Monday, May 16 6 p.m. - 8 p.m.; Wednesday, May 18 7 p.m. - 8:30 p.m.: Apostolic Assembly The Faith (424 E. Frontier St., Eloy).
Tuesday, May 17: Villa Oasis High School graduation (3740 N. Toltec Rd., Toltec) from 6 p.m. - 9 p.m.