Swiss pharmaceutical company Roche Holding AG (search) said Thursday it had temporarily suspended shipments of the anti-viral drug Tamiflu (search), the drug experts believe is most effective in treating flu in humans, in the United States.
Roche spokesman Alexander Klauser said that Roche's U.S. management suspended the shipments to wholesalers and other private sector recipients because of the increased global demand for Tamiflu.
Demand has soared over fears of the potential spread of bird flu.
"The priority is that there is enough Tamiflu for the people who need it at the start of the influenza season," Klauser told The Associated Press. "At the moment, there is no influenza currently circulating."
Health experts have been pinning their hopes on Tamiflu in case bird flu (search) mutates into a form that can be passed easily between people. While there is no human vaccine for the spreading strain of bird flu, scientists believe Tamiflu may help humans fight a mutated virus.
Klauser said the increased demand would mean that "over the next few weeks, limited stocks would be available in most countries." But he said the suspension, reported Thursday by The New York Times, would not affect the U.S. government's order for Tamiflu.
Tamiflu is one of four drugs that can treat regular flu if taken soon after symptoms begin.