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Guangdong Vice Governor Lei Yulan visits Guangdong's 1st A/H1N1 flu patient in No. 8 People's Hospital of Guangzhou.

Guangdong Vice Governor Lei Yulan visits Guangdong's 1st A/H1N1 flu patient in No. 8 People's Hospital of Guangzhou.

Chinese health authorities have begun tracing passengers who may have traveled in the same train carriage with a man who was reported Monday to be a new case of A/H1N1 flu on the mainland.

The man, surnamed Yang, returned to China's mainland Friday from a tour of the United States and Canada, according to a notice from the Ministry of Health.

He flew into Hong Kong via the Republic of Korea Wednesday, then took a train to the southern coastal province of Guangdong on Friday, said a ministry official.

A total of 65 out of the 93 people exposed to Yang on train T810 had been contacted by health departments and were put under quarantine.

Guangdong Provincial Center for Disease Control and Prevention confirmed Monday that Yang caught Korean Air flight KE020 from Seattle to Seoul May 12. He then transferred to Korean Air flight KE607 to Hong Kong Wednesday, May 13.

Xinhua contacted Korean Air by phone, but airline officials refused to say how many passengers shared flights with Yang.

Guangdong Provincial Health Department said Monday Yang was admitted into the No. 8 People's Hospital of Guangzhou on Friday afternoon.

Yang, a native of Guangzhou, Guangdong's provincial capital, lives in Nanhai. In late April, he joined a tour group visiting Canada and the United States.

Yang's itinerary in Canada and the United States, as well as Hong Kong was not immediately known.

According to the Guangdong Provincial Health Department, he developed a sore throat, stuffy nose, and a cough on Thursday. He caught the two-hour train in Hong Kong at 4:35 p.m. Friday, riding in carriage No. 7.

Yang had normal temperature when he boarded the train, but he developed a fever halfway through the journey. He was taken to the No. 8 People's Hospital for isolation and medical treatment, said provincial health authorities.

Experts from Guangdong Provincial Bureau of Quality Supervision, Inspection and Quarantine and other local health organizations conducted laboratory tests Sunday. The result was A/H1N1 positive. Guangdong Provincial Health Department had the tests double-checked the same day and concluded he was suspected to have contracted A/H1N1.

The Chinese Health Ministry confirmed Monday it had received a report from Guangdong Provincial Health Department at midday about the suspected A/H1N1 flu case.

The health ministry has also informed the World Health Organization, the United States, Canada, the Republic of Korea, as well as Hong Kong about the new suspected flu case in Guangdong.

Provincial health authorities said Yang regained a normal temperature Monday afternoon, and his condition was stable.

If the diagnosis is confirmed, Yang will become the fourth known case of A/H1N1 flu on the Chinese mainland. The other three were located in Chengdu, capital of Sichuan Province, Jinan, capital of Shandong Province, and Beijing.

Editor: Yan