UN has warned against the spread of the H1N1 virus after turkeys on farms in Chile were found infected by the disease.
The United Nations suggested the possibility that poultry farms elsewhere in the world may also be affected.
Chilean authorities reported two affected poultry farms near the seaport of Valparaiso and had set up temporary quarantine, letting the infected birds to recover rather than culling them.
Dr Lubroth added: "In Southeast Asia there is a lot of the (H5N1) virus circulating in poultry. The introduction of H1N1 in these populations would be of greater concern."
Colin Butter, from the UK's Institute of Animal Health, also said: "We hope it is a rare event and we must monitor closely what happens next.
"However, it is not just about the H5N1 strain. Any further spread of the H1N1 virus between birds, or from birds to humans would not be good.
"It might make the virus harder to control, because it would be more likely to change."
However, swine flu remains no more severe than seasonal flu, it was said.