The plot has thickened when it comes to China and bird flu.
It appears one of the researchers who reported that a Chinese man may have died from avian influenza before anyone else in China was known to have the disease, has denied trying to retract the article.
Dr. Wu Chun Cao of the State Key Laboratory of Pathogens and Biosecurity in Beijing says that e-mails bearing his name sent to the The New England Journal of Medicine were not written or sent by him.
The case has caused grave concern and the authenticity of the letter sent to the journal reporting the case is critical.
The letter reinforced widely held suspicions there were earlier and more human bird flu cases in China than authorities ever admitted to.
The prestigious journal says it received an e-mail signed with the researcher's name that requested the letter reporting the case be withdrawn from publication.
Wu has since telephoned the journal's editors and sent a fax denying he ever made any such request.
Wu, a senior scientist in China, was one of eight researchers who reported in the journal that a 24-year-old man who died of pneumonia in November 2003 and was at first suspected as a SARS victim may have in fact died of avian influenza as all tests were negative for SARS.
Tests of his tissue were however positive for the influenza virus, and genetic sequencing later showed it to be H5N1 avian influenza and genetically similar to viruses taken from Chinese chickens in various provinces in 2004.
SARS first broke out in China's southern Guangdong province in 2002 and spread as far as Canada before it was brought under control in 2003.
It killed almost 800 people out of the 8,000 known to have been infected.
At the time flu experts assumed the then-mysterious respiratory illness sickening people in China was H5N1 avian influenza, which broke out in Hong Kong in 1997 and then disappeared.
Influenza experts say flu viruses rarely just disappear and had been waiting for its return, which was reported in 2003.