Porn mogul Hugh Hefner's famed California abode, the Playboy Mansion is at the centre of a health investigation after 170 people, who had attended a fundraiser there, reportedly fell ill.

Los Angeles County health officials said that the possible outbreak of legionellosis, or Pontiac fever, had affected people who attended the February 3 Domainfest Global Conference held at the mansion, reported Los Angeles Times. But Hefner has shot down reports that a fog machine used at a recent party is to blame for a virus outbreak among a group of guests.