Hollywood's celebrities may have been exposed to the hepatitis A virus at one of 13 catered events, in particular a Sports Illustrated's swimsuit party.
Caterers Wolfgang Puck who provided the food for the events have revealed that an employee has been diagnosed with the hepatitis A virus.
According to Dr. Jonathan Fielding, Los Angeles County director of public health, as many as 3,500 people may have been exposed to the contagious illness between February 3rd and the 20th.
Health officials fear guests at several events may have been exposed to the virus and anyone who ate uncooked food at the sports magazine's party on February 14th should be treated in order to avoid developing the serious liver disease.
Health officials say the risk is low and no Wolfgang Puck pre-packaged foods or restaurants were affected.
Health officials and party organizers are working to notify all of the people on the 13 party guest lists.
Hepatitis A is caused by a virus spread by ingesting something contaminated with the feces of an infected person and can be spread through contaminated food and water.
It attacks the liver and can cause fever, diarrhea and jaundice, but is rarely fatal.
It can be spread when an infected worker touches food, even cooked food, without taking proper precautions.
The virus is most often spread through fecal-oral contact, such as touching hand to mouth after using the bathroom or shaking the hands of infected people who have not washed properly.
Carl Shuster, the president of Wolfgang Puck Catering, says the company is working closely with health officials to contact anyone who ate food prepared in its Hollywood kitchen between February 1st and the 20th.
The worker concerned has been placed on medical leave and the company has disinfected the kitchens and food processing areas.
Sports Illustrated is also taking the situation very seriously and is working directly with county health authorities to alert guests and staff as quickly as possible in order to ensure they receive the relevant health warnings.
The party centered around the current swimsuit issue featuring singer-actress Beyonce Knowles as the cover model, with rapper Kanye West, country star Kenny Chesney and members of the bands Aerosmith and Gnarls Barkley, many of whom were present at the party along with the models used.