Beyonce Knowles and Leonardo Dicaprio's girlfriend BAR RAFAELI have been left reeling by a health alert - they could have been exposed to hepatitis A. Officials at the Los Angeles County Department Of Public Health have confirmed an employee of celebrity chef Wolfgang Puck, who was working at a recent party the ladies attended, has been diagnosed with the disease, according to And now all guests and staff at the Sports Illustrated Swimsuit Issue party on 14 February (07) and all other events catered by Puck's company in Hollywood between 1 February and 20 February have been advised to seek medical help immediately. The health experts suggest all those who may have come into contact with the sick Puck employee should get an immune globulin shot to prevent illness. Meanwhile, a spokesman for Puck insists no one who attended Sunday's (25FEB07) post-Oscars Governor's Ball, which the chef catered, is at risk.