Australians who have travel plans to China are advised to take precautionary measures as the country's health ministry announced two people have been inflicted with the contagious H5N1 bird flu virus.
Although no epidemiological connections have been found between the two cases, the patients, a 21-year-old woman and a 31-year-old man, are both in critical condition, state news agency Xinhua said on Sunday, quoting unidentified officials from the health ministry.
"Medical workers are carrying out emergency treatment," the health ministry said.
The patients both came from the southwestern city of Guiyang. After developing symptoms on February 2 and February 3 respectively, both eventually tested positive for the highly pathogenic H5N1 virus on Sunday.
According to the World Health Organization, H5N1 is a type of influenza virus that causes a highly infectious, severe respiratory disease in birds called avian influenza, or "bird flu." Human cases of H5N1 avian influenza occur occasionally, but it is difficult to transmit the infection from person to person. When people do become infected, the mortality rate is about 60 per cent.
With the onset of the Lunar New Year, it is possible that infectious diseases could happen and further spread as millions of Chinese travel in overcrowded buses and trains across the country.
Xinhua said health ministry officials are currently observing the people with whom the two patients had recent contact. None so far have been found ill so far, the agency said.
Xinhua likewise the pair did not have contact with birds before developing the symptoms.
At least 365 people worldwide have died due to the bird flu virus since a major outbreak in 2003, according to the World Health Organisation.
Global health experts remain concerned the disease could mutate into a form that could spread easily among humans.
Almost all cases of H5N1 infection in people have been associated with close contact with infected live or dead birds, or H5N1-contaminated environments. The virus does not infect humans easily, and spread from person to person appears to be unusual. There is no evidence that the disease can be spread to people through properly prepared and thoroughly cooked food.