The World Health Organisation has stood by its advice on swine flu treatment with the antiviral drug Tamiflu in "severe and progressive" infections, a report said.

The WHO decision is despite a study which warned against the use Tamiflu by children, said the AFP report.

"WHO continues to recommend use of antivirals as treatment for people who are severely ill or are at risk of other health complications," the WHO said in a response to questions about the recent study said the report.

However, it also stressed that the antiviral, made by Swiss pharmaceutical giant Roche, should not be taken by those showing just mild flu-like symptoms.

The study published Monday in the British Medical Journal said that children with seasonal flu should not be given Tamiflu because harmful side effects may outweigh relatively meagre benefits. The study did not cover the current outbreak of swine flu.