[1] Clinton Hlth Access Initiat, Abuja, Nigeria
[2] US Ctr Dis Control & Prevent, Abuja, Nigeria
[3] Fed Minist Hlth, Natl AIDS & STI Control Programme, Abuja, Nigeria
[4] Jos Univ, Teaching Hosp, Dept Internal Med, Jos, Nigeria
[5] Lagos Univ, Teaching Hosp, Dept Microbiol, LAGOS, Nigeria
[6] Lagos Univ, Teaching Hosp, Dept Haematol, Lagos, Nigeria