RICHMOND, Va. (UPI) -- A national survey of 2,765 men and women shows Americans are more sexually active than they were in 1990 despite the specter of AIDS, two former University of Virginia researchers say.

``Most Americans regard sex as part of the Bill of Rights,'' said Dr. Samuel Janus, who with his wife, Dr. Cynthia Janus, wrote ``The Janus Report on Sexual Behavior.''

Their report is being touted as the most comprehensive study on American sexual behavior since the Kinsey report four decades ago.

More than four out of every five respondents in the survey said they were gravely concerned about sexually transmitted disease, but nearly three of every four men and more than two out of every three women reported maintaining or increasing their sexual activity.

``Most Americans seem to feel AIDS is a problem for gays and the poor, and that they're immune,'' he said.

Evidence demonstrating heavy sexual activity among people older than 65 is one of the survey's more important findings, Janus believes.

``People over 65 are not only able but eager to have sex,'' he told the Richmond Times-Dispatch in a phone interview from Boston, where he's starting a national book tour.

Janus said 14 percent of men over 65 reported having sex daily. Only 1 percent of women over 65 reported having daily sex, but he said that's probably because many are widows.

``A real life force continues on in maturity and keeps people alive,'' he said.

The survey, which included 125 in-depth interviews, also found:

Cynthia Janus was an associate professor of radiology and of obstetrics and gynecology from 1988 to 1991 at U.Va. Samuel Janus, a psychologist, was a part-time faculty member serving as a clinical associate professor of behavioral medicine from 1988 to 1992.

Their book sprang from nine years of research, they said, though none was conducted at U.Va. The couple now lives in Vineland, N.J.