Aging presents new challenges to people living with HIV and an ever greater number are having to face them. Some older people have had HIV for decades but many others are being newly diagnosed. The number of men and women over 50 who are testing positive for HIV is rising; half were infected recently and a quarter already have AIDS at the time of diagnosis. Screening isn’t commonplace in this age group and risk factors haven’t been studied. In the United States, more than half of all people living with HIV will be over 50 by 2015.