OTTAWA - World health ministers meeting in Canada to discuss strategies to fight the spread of bird flu emphasized Monday that preventing the disease from mutating into a deadly human virus was as important as developing new vaccines against it.

That said, some officials at the opening of a two-day conference on battling a potential flu pandemic were discussing whether they might have to break international patent regulations to produce generic versions of Tamiflu if it came down to saving their civilians.

The deadly H5N1 strain of bird flu has been confirmed in Russia, Romania and Turkey, and experts in Britain were trying to determine Monday whether six Croatian swans found last week had H5N1 — a strain that scientists fear could mutate into a virus that would easily spread person-to-person.