This year's U.S. flu season has created shortages of the Tamiflu treatment for children and of the most widely used flu vaccine, their manufacturers said. Roche Holding AG told Reuters late on Wednesday that it had a shortage of the liquid form of Tamiflu, given to children who already have the flu to slow or stop symptoms. A spokeswoman for the U.S. Food and Drug Administration confirmed that there have been supply interruptions in some locations.