Hepatitis A is a bad illness- not as bad as hep B or C but it can be very serious for some people. Now it’s been revealed that the US Health Department has issued an urgent warning to the star studded crowds who attended the Sports Illustrated Swimsuit Issue Party on Valentines Day that they may have been exposed to acute Hepatitis A.

Possibly exposed guests include Leonardo DiCaprio’s girlfriend Bar Rafaeli, Beyonce Knowles, and dozens of models who attended the event.

The Los Angeles County Department of Public Health has confirmed that a member of Wolfgang Puck Catering’s staff was diagnosed with the disease recently, and they have strongly urged anyone that attended the Sports Illustrated party or any of the 13 other events that were catered by Puck between Feb. 1st and 20th to get an immune globulin shot by today to prevent the illness.

It’s not known how many people might have been exposed to the illness in total, but it is known that none of the guests who attended the Governor’s Ball at the Academy Awards were at risk.