Background: HPTN071 (PopART) is a community-randomised trial evaluating the impact of a combination HIV-prevention intervention on HIV incidence. Overall, this intervention has reached the first UNAIDS 90, yet men and younger adults still have lower knowledge of HIV status. We nested a cluster-randomised trial of oral HIV self-testing (HIVST) in addition to rapid finger-prick HIV testing (HIVFP) offered door to door by lay counsellors (CHiPs) within HPTN071 to evaluate the impact on knowledge of HIV status.
Methods: Four of the Zambian HPTN071 intervention communities were randomised by CHiP zones, with an average of 471 households per zone. In HIVST zones (n=33/N=66), individuals aged >16 years who did not self-report being HIV-positive, were offered a choice of HIVST or HIVFP. Secondary distribution of HIVST was offered for absent partners. A population-average logistic regression model was used to estimate the effect of the HIVST intervention on knowledge of HIV status (definition: self-report HIV-positive or accepted HIV testing services), using total population enumerated as the denominator, adjusting for community, sex and age, and accounting for clustering by zone.
Results: Between February 1st and April 30th 2017, 63.3% (8,139/12,852) of adults enumerated in the HIVST arm knew their HIV status compared to 61.3% (8,203/13,383) in the non-HIVST arm, adjusted OR 1.25 (95% CI 1.01-1.56, p=0.04). Women had high knowledge of HIV status (71.1% in both HIVST and non-HIVST, adjOR 1.03, 95%CI 0.85-1.25, p=0.74). Among men, knowledge of HIV status was 55.0% in HIVST compared to 50.2% in non-HIVST (adjOR 1.30, 95%CI 1.07-1.60, p=0.01), with strong evidence that the effect of the HIVST intervention was different for men and women (p=0.004; Table).

CharacteristicEnumerated in non-HIVST ZonesKnows HIV-status in non-HIVST ZonesPercent (%)Enumerated in HIVST ZonesKnows HIV-status in HIVST ZonesPercent (%)Odds Ratio95% Confidence Intervalp-value
Sex: Male6,3113,17150.26,2003,41255.01.301.07-1.600.01
Sex: Female7,0725,03171.16,6524,72771.11.030.85-1.250.74
Age (yrs): 16-296,8414,54166.46,5654,50868.71.241.01-1.530.04
Age (yrs): 30 and above6,5423,66256.06,2873,63157.81.200.97-1.480.10
Community 13,6701,97153.73,5851,93353.91.010.79-1.290.93
Community 21,56771545.61,65099260.11.991.39-2.85<0.001
Community 34,1502,47759.74,6042,78460.51.170.88-1.550.29
Community 43,9963,04076.13,0132,43080.71.450.68-3.100.34
[Knowledge of HIV status in non-HIVST & HIVST zones]

Conclusions: Introducing HIVST for 3 months in communities already exposed to door-to-door HIV-testing services for 3 years, increased the proportion of the population who knew their HIV status. This effect was seen most markedly in men.