As of 5 p.m. Thursday, a total of 81people from Jiangxi University of Traditional Chinese Medicine in Nanchang --77 students and four teachers-- had contracted hepatitis A, 17 more than the number released on Tuesday.

All those who have been diagnosed with the disease have been hospitalized, said the the Jiangxi Provincial Health Department, adding that the students are in a stable condition.

14 of the suspected student hepatitis A carriers were discharged from hospital on Wednesday after several days of medical observation.

But about 15 classmates are still hospitalized because the local hospital still cannot completely rule out the possibility that they were not infected with the disease.

An investigation has traced the cause of the outbreak to two canteen workers, who were hepatitis A carriers, according to the health department.

Medical workers will supervise the disinfection of student dormitories as well as public places on campus.

The department said some students from the university's suburban Wanli campus began to feel a loss of appetite and dwindling strength on Sunday.

It also said there might be more cases on campus because hepatitis A is highly infectious and its incubation period lasts 15 to 30 days.

Provincial, city and district level health departments have been mobilized to prevent the spread of the disease.

Thirty-eight people in a school in South China's Guangxi Zhuang Autonomous Region also have hepatitis A and 30 others may have come down with the disease.

An initial investigation suggests contaminated drinking water is the cause of the outbreak. The first case was found on Nov. 23 and the outbreak spread on Dec. 6.

The students' main supply of drinking water-- a well in the junior middle school --may have been contaminated by a drainage ditch only five meters away.

In August, an outbreak of hepatitis A affected 69 high school students in the same region.

Hepatitis, or inflammation of the liver, is caused by infectious or toxic agents and characterized by jaundice, fever, liver enlargement, and abdominal pain.

Source: Xinhua