“…Studies from Vietnam [3,[5][6][7], Thailand [8], China [9,10], South Asia [11], Indonesia [12], Russia [13], and the U.S. [8,14,15] reveal low rates of condom use by IDUs with their primary sexual partners, especially their wives and regular girlfriends. Most of this literature does not address the very serious dimension of HIV serodiscordance in primary sexual relationships.…”