[1] Catholic Univ Hlth & Allied Sci, Weill Bugando Sch Med, Dept Obstet & Gynecol, Mwanza 1464, Tanzania
[2] Catholic Univ Hlth & Allied Sci, Weill Bugando Sch Med, Dept Microbiol & Immunol, Mwanza 1464, Tanzania
[3] Muhimbili Univ Hlth & Allied Sci, Dept Microbiol & Immunol, Mwanza 65001, Tanzania
[4] Natl Inst Med Res Headquarters, Dar Es Salaam 9653, Tanzania