[1] Southern Med Univ, Dermatol Hosp, STD Control Dept, Guangzhou, Peoples R China
[2] Southern Med Univ, STD Control Dept, Inst Global Hlth & Sexually Transmitted Dis, Guangzhou, Peoples R China
[3] Guangdong Prov Ctr Skin Dis & STIs Control, STD Control Dept, Guangzhou, Peoples R China
[4] Univ N Carolina, Project China, Chapel Hill, NC, Peoples R China
[5] Sun Yat Sen Univ, Dept Ophthalmol, Affiliated Hosp 3, Guangzhou, Peoples R China