37-year-old mother karlie illg slaven from indiana, one of the flu epidemic's latest victims. her father says she'd been taking care of her husband and children who had the virus when she started feeling sick. >> my wife called and said, "get over here right away. they put her in the icu. she's in critical condition." >> reporter: he says she died just three days after testing positive for the flu. >> we all were there, standing around her, and she left us about 6:30 in the morning. >> reporter: karlie's story, highlighting the danger to caregivers and others at home. tonight, the cdc recommending that some people at a higher risk take a preventative dose of tamiflu, even if they don't have the flu. a step that could cut their chances of getting the virus by up to an estimated 80%. >> if there are infections in the household, and you are concerned about an older individual in the home, talk with your doctor and see if prophylactic medicines are something that would be useful. >> reporter: across the country, nearly 12,000 flu patients so sick they've had to be