u.s. food drug administration open door tuesday change blood donor deferral recommendations currently prohibit donations gay men year follow last sexual encounter order reduce risk transmit hiv virus cause aid december fda overturn 30-year ban blood donations men sex men say change base science show indefinite ban necessary prevent transmission human immunodeficiency virus fda signal may go gay right advocate say late update go far enough agency recommendations move close individual risk assessments could example look whether individual monogamous relationship criticism intensify wake mass shoot gay nightclub orlando florida june saw many gay men unable donate blood even blood bank put call donors notice post federal register fda say establish public docket comment current recommendations interest people submit comment back scientific evidence support alternative potential policies reduce risk hiv transmission suggestions could include feasibility move exist time-based deferrals relate risk behaviors alternate deferral options use individual risk assessments agency say would take comment account continue reevaluate update blood donor deferral policies new scientific information become available fda action come 115 members u.s. house representatives lead democrat mike quigley vice chair congressional lgbt equality caucus write fda commissioner robert califf call end current policy say discriminate men sex men similar letter sign 22 senators statement tuesday quigley say encourage fda announcement tragedy pulse nightclub orlando highlight discrimination gay bisexual men face attempt donate blood need say move towards individual risk assessment would provide fair equitable nondiscriminatory blood donation policy one base science allow healthy americans safely donate blood u.s. open door change blood donation policy gay men