A study published by the U.S. Centers for Disease Control and Prevention rejects the widely held perception that blames U.S. prisons for the spread of the AIDS epidemic, saying very few prisoners acquire the virus.

The study also refutes the notion that incarceration contributes directly to the high rate of HIV among black men.

Researchers compiled nearly two decades of investigations and data from Georgia's prison system, the nation's fifth largest with nearly 45,000 inmates.

The study revealed 90 percent of HIV-positive men in the prison system contracted the disease before their incarceration. Over the 17-year study, only 88 men became infected in prison by the virus chiefly through same-sex intercourse.

Investigators also revealed much to the authorities of those who got infected behind bars acknowledged having gay sex there, half reported their partners were prison staff members, not other inmates. It still remains unclear if the officers were the source infection or became infected themselves.

The study also said about three-quarters of inmates who reported having had sex with other men described it as consensual.