Health officials in New Jersey have issued a measles exposure warning after an individual infected with the virus attended a Shakira concert at MetLife Stadium in East Rutherford on May 15, potentially exposing tens of thousands of concertgoers.

Thousands of people who attended a Shakira concert in New Jersey last week have been issued an urgent health warning following an outbreak of the measles. The Colombian singer’s show at the MetLife Stadium on May 15 could prove to be the epicenter of a major superspreader event after health officials identified a concertgoer “associated with a newly identified case of measles in a non-NJ resident who attended a concert in NJ while infectious.