A new, heavily prescribed and marketed flu medication shortens the duration and severity of the illness, a study says, but only by about a day and a half - and scientists are questioning whether it and a similar drug are worth the expense. A report in today's Journal of the American Medical Association confirms that oseltamivir, the ingredient in Tamiflu, reduced symptoms and got people back on their feet faster than a placebo in a study of 629 people with respiratory illness.