"We have asked scientists in our collaborating centers, and in animal health, specialists also, to look into this and see whatever evidence there is one way or the other," WHO spokesman Gregory Hartl told a news briefing in Geneva.
But for the moment "it is very too soon to say anything on these claims," Hartl said.
According to Bloomberg News, Adrian Gibbs, 75, said he intends to publish a report suggesting the new flu virus may have accidentally evolved in eggs scientists use to grow viruses and drug makers use to make vaccines.
Gibbs said he came to his conclusion as part of an effort to trace the virus's origins by analyzing its genetic blueprint.
According to latest figures issued by the WHO, the A/H1N1 virus has so far spread to 33 countries infecting 5,728 people.