They say a person who attended games on Friday at Cedar Grove Park and Saturday at Exchange Club Park in Hillsborough developed measles symptoms on Sunday.
If you attended the games on May 3 or 4, please be alert for symptoms that could occur anytime between May 10 and May 25. Health officials say if you develop symptoms, stay home and call your medical provider to be tested.
Measles is a viral illness that is spread through respiratory droplets. Symptoms include fever, cough, runny nose, red eyes and a rash that begins on the head and moves down.
Persons born before 1957 are likely immune due to having had the disease as a child.
Most people who have measles recover without complications, but it is especially dangerous for pregnant women, infants and persons with other health conditions that would be complicated by measles.
For more information about measles, please visit http://www.cdc.gov/measles/.