�������t¶��

"We encourage all countries to increase their ability to monitor these viruses and to detect any human cases," said Dr Sylvie Briand, the director of epidemic and pandemic preparedness and prevention at the WHO.

"WHO takes the risk from this virus seriously and urges heightened vigilance from all countries," Briand said.

"The global H5N1 situation is worrying given the wide spread of the virus in birds around the world and the increasing reports of cases in mammals including humans," said Briand.

Briand said it was not yet clear whether there had been any human-to-human transmission or if the two cases were due to the "same environmental conditions", likely close contact with infected birds or other animals.

Describing the situation as "worrying" due to the recent rise in cases in birds and mammals, Dr Sylvie Briand, the director of epidemic and pandemic preparedness and prevention, told reporters in a virtual briefing that WHO was reviewing its global risk assessment in light of the recent developments.