Researchers have identified a mysterious new disease that has left scores of people in Asia and some in the US with AIDS-like symptoms even though they are not infected with HIV. The patients' immune systems become damaged, leaving them unable to fend off germs as healthy people do. What triggers this isn't known, but the disease does not seem to be contagious. This is another kind of acquired immune deficiency that is not inherited and occurs in adults, but doesn't spread the way AIDS does through a virus, says Dr. Sarah Browne of National Institute of Allergy and Infectious Diseases.
She helped lead the study with researchers in Thailand and Taiwan where most of the cases have been found since 2004. The disease develops around age 50 on average but does not run in families, which makes it unlikely that a single gene is responsible. Some patients have died of overwhelming infections, including some Asians now living in the US, although Browne could not estimate how many. Researchers are calling this new disease an "adult-onset" immunodeficiency syndrome because it develops later in life and they don't know why or how. The disease quiets in some patients once the infections are tamed, but the faulty immune system is likely a chronic condition. (Read more AIDS stories.)