One suspected case of A/H1N1 influenza was reported in southwest China's Sichuan Province, the Ministry of Health (MOH) said on Sunday.

The case, the first of its kind in the Chinese mainland so far, involved a 30-year-old man surnamed Bao. He had just returned to Chengdu, capital of Sichuan, from St. Louis of the United States via Tokyo on Saturday afternoon. He studied at a US University.

Bao had traveled on flight NW029 from Tokyo and arrived at the Beijing International Airport on Saturday. He then flew from Beijing to Chengdu on flight U8882 the same day, the ministry said.

According to the Sichuan health department that reported the case to the MOH on Sunday afternoon, Bao was found with fever in the Sichuan People's Hospital and was "initially diagnosed as suspected A/H1N1 influenza case" based on his symptoms and laboratory tests.

Bao was transferred to the Chengdu Infectious Disease Hospital, the ministry said.

The MOH said Bao developed symptoms of fever on the flight from Beijing to Chengdu accompanied by sore throats, coughing, stuffy nose and sneezing. He went to the Sichuan People's Hospital after getting off the plane.

He was tested "weakly positive" to A/H1N1 virus twice by the Sichuan Center for Disease Control and Prevention, it said.

The MOH has sent expert team to Chengdu and asked the local health authorities to immediately send the virus specimen to the Chinese Center for Disease Control and Prevention for a second check.

The ministry has asked the Sichuan authorities to strengthen treatment of the patient, search all the people who had close contact with Bao and conduct relevant epidemiological investigation.

It has informed provinces and municipalities concerned to immediately look for the people who had close contact with Bao, and called for passengers of the two flights to contact health authorities as soon as possible.

According to the Sichuan Center for Disease Control, Bao's girlfriend and his father who were in close contact with Bao, have been put into quarantine.

Also in quarantine was a local taxi driver who was in close contact with Bao, according to Sichuan Provincial Department of Public Health.

The department also said there were altogether 150 passengers aboard the flight U8882 and more than 130 of them had been found.

The ministry has reported the case to the World Health Organization and relevant countries and regions.

In Beijing, a man with a fever after a shared flight with three people who were later diagnosed with A/H1N1 influenza, was cleared of the virus after being tested negative, the emergency office of the Beijing municipal government said on Sunday.

The man, a native of Beijing, was aboard the US airlines NW025, which flew from Canada to Japan via the United States on Friday. Three Japanese passengers aboard the plane were later tested positive for A/H1N1 influenza.

The man, whose name remained unknown, arrived Beijing Friday night, when his body temperature was normal. He developed fever on Saturday and was put under medical observation immediately.

(Xinhua News Agency May 11, 2009)