Ashton Kutcher's party guests told they must be tested for hepatitis

Movie hunk Ashton Kutcher and showbiz pals including Madonna, Gwyneth Paltrow, Salma Hayek and Bruce Willis are at the center of a Hepatitis A scare.

It has emerged one of the bartenders serving at the New York hotspot where Ashton had his 30th birthday party earlier this month has the highly contagious liver disease.

The NYC Department of Health is urging the stars and up to 800 revellers who may have been served by the barman at Socialista to get a hepatitis shot as soon as possible.

Ashton's bash was held on February 7. The bartender also served drinks on February 8 and 11.

Socialista last night issued a statement saying: "Although no additional cases of illness have been identified, the New York City Department of Health is urging customers to get the vaccination as a precautionary measure.

"We are grateful for their efforts and we will continue to support them in every way possible."

Heptatitis A is spread by putting something in the mouth that has been contaminated with traces of fecal matter from an infected person.

Symptoms include jaundice, fatigue, abdominal pain, nausea, and diarrhea.