Maricopa County health officials have identified additional measles exposure sites, including a concert at Chase Field and a mall in the Chandler area. The update means people who attended the event or visited the East Valley shopping location may have been exposed.

According to the Maricopa County Department of Public Health, the newly listed sites are part of an ongoing effort to notify the public about places where exposure may have occurred. Officials are using the location alerts to help residents determine whether they may be at risk and whether they should watch for symptoms.

Measles is highly contagious, which is why public health agencies closely track possible exposure settings such as large venues and busy retail centers. Concerts, shopping malls and other crowded indoor locations can increase the number of people who may have crossed paths with an infected person.

Residents in Maricopa County who were at Chase Field for the concert or at the Chandler-area mall during the relevant time period are being urged to pay attention to public health guidance. The latest alert adds to concern about measles exposure in the Phoenix area as officials continue contact tracing and public notifications.