A mainland man who died of bird flu passed the disease on to his father in the latest human case, the Ministry of Health confirmed yesterday.
But ministry spokesman Mao Qunan said there was no evidence that the virus had mutated into a form that was easily transmissible among humans.
He said the 52-year-old father in Jiangsu province was infected through close contact with his 24-year-old son, who died last month. 'The initial judgment is that it was an infection from close contact,' Mr Mao said. 'It has no biological features for human-to-human transmission.'
He said the father had recovered.
However, Mr Mao said experts still could not determine the source of infection for the father and son, as both had no known history of contact with dead poultry or birds - the primary source of H5N1 bird flu.
The World Health Organisation said yesterday it would not rule out the possibility of animal-to-human infection in the case and there was no immediate threat of an epidemic because the virus had not mutated into a form that could jump easily between humans.
