February 17, 2012
"Lack of education and an economic dependence on men are often suggested as important risk factors for HIV infection in women," wrote the authors, whose current study assessed the efficacy of a cash transfer program to reduce the risk of STIs in young women.
The cluster randomized trial recruited never-married women ages 13-22 from 176 enumeration areas in Malawi's Zomba district. The women were randomly assigned with computer-generated random numbers by enumeration area (1:1) to receive cash payments (the intervention group) or nothing (the control group). In addition, the intervention enumeration areas were randomly assigned with computer-generated random numbers to conditional (school attendance was required to receive payment) and unconditional (nothing was required to receive payment) groups.
In both intervention groups, participants were assigned by lottery to receive monthly payments ranging from US $1-$5. Their parents were independently assigned with computer-generated random numbers to receive $4-$10. At baseline and at 12 months, behavioral risk assessments were performed. Serology was tested at 18 months. Although the participants were not masked to treatment status, the counselors who performed the serologic testing were. The study's primary outcomes were prevalence of HIV and herpes simplex virus 2 (HSV-2) at 18 months; these were assessed by intention-to-treat analyses.
Eighty-eight enumeration areas were assigned to the intervention, and 88 to the control condition. Among the 1,289 individuals enrolled in school at baseline with complete interview and biomarker data, weighted HIV prevalence at 18 months was 1.2 percent (seven of 490 participants) in the combined intervention group, compared to 3.0 percent (17 of 799 participants) in the control group (adjusted odds ratio 0.36, 95 percent CI: 0.14-0.91); weighted HSV-2 prevalence was 0.7 percent (five of 488 participants), versus 3.0 percent (27 of 796 participants) (AOR 0.24, 0.09-0.65).
The authors noted no difference between the conditional and unconditional intervention groups for weighted HIV prevalence (3/235 [1 percent] vs. 4/255 [2 percent]) or weighted HSV-2 prevalence (4/233 [1 percent] vs. 1/255 [<1 percent]). Among individuals who had already dropped out of school at baseline, no significant difference was noted between intervention and control groups for weighted HIV prevalence (23/210 [10 percent] vs. 17/207 [8 percent]) or weighted HSV-2 prevalence (17/211 [8 percent] vs. 17/208 [8 percent]).
"Cash transfer programs can reduce HIV and HSV-2 infections in adolescent schoolgirls in low-income settings," the authors concluded. "Structural interventions that do not directly target sexual behavior change can be important components of HIV prevention strategies."