The demand was made in a letter dated Thursday that was written by two doctors at the University of California, San Francisco, and signed by hundreds of medical professionals at places like Emory University, Harvard Medical School and the University of Florida. More than 500 doctors, researchers and public health specialists are calling on the Food and Drug Administration to eliminate constraints on blood donations by gay and bisexual men, saying the agency did not go far enough when it relaxed its restrictions earlier this month.
