The mysterious disease that recently plagued residents of a village in Leizhou, Guangdong Province, has been established as influenza.

About 500 residents of a village in Leizhou, most of whom were children, were infected by an unknown disease, probably a kind of viral respiratory tract infection, Yangcheng Evening News in Guangzhou reported over the weekend.

Guangdong's Department of Health alerted Hong Kong's Centre for Health Protection (CHP) about the outbreak, a CHP official said yesterday. The number of people involved as of yesterday was officially put at 286.

According to the Guangdong report, the affected people, most of whom were students, had developed very mild symptoms of respiratory tract infection, including fever, coughs and myalgia.

Preliminary laboratory tests of samples taken from the affected students indicated that the outbreak was due to the human influenza virus.

None of those who fell ill had to be hospitalized, but the schools involved have been closed.

York Chow, secretary for Health, Welfare and Food, said that he had asked for detailed laboratory test reports about the virus.

Chow will lead a delegation to Guangzhou tomorrow to strengthen ties with relevant government departments there.

During the three-day visit to Guangzhou, Chow will meet with officials of the Department of Health, the Department of Civil Affairs and the Entry-Exit Inspection and Quarantine Bureau of the Guangdong Province.

He will visit the Guangdong Provincial People's Hospital, an elderly hostel, a registered chicken farm which supplies to Hong Kong and a processing plant of chilled chickens.

Guangdong health authorities said they have already taken measures, including disinfection and health education, to control the outbreak. They predicted that the epidemic situation would be brought under full control within five days.

The CHP pledged to maintain close liaison with its mainland counterpart with a view to monitoring the situation.

Thomas Tsang Ho-fai, CHP's consultant (communicable disease), commented that an increase in influenza cases in Guangdong at this time is nothing surprising as it is now the high season for influenza in the province.

(China Daily HK Edition April 26, 2005)