Table 2. Expected versus observed HIV incidence.
| Expectation from Partners
PrEP Study * |
Observed from Partners
Demonstration Project |
Incidence rate
ratio (95% CI) p-value |
Effectiveness
(95% CI) |
|||
|---|---|---|---|---|---|---|
| N incident
infections/ N years follow up |
Incidence ** | N incident
infections/ N years follow up |
Incidence ** | |||
| Overall incidence | 80.7/1700.2 | 4.75 | 4/1682.3 | 0.24 | 0.05 (0.02, 0.14)
p<0.0001 |
95%
(86–98%) |
| By gender | ||||||
| Women | 42.0/553.0 | 7.60 | 3/560.4 | 0.54 | 0.07 (0.02, 0.23)
p<0.0001 |
93%
(77–98%) |
| Men | 41.1/1144.6 | 3.59 | 1/1121.9 | 0.09 | 0.03 (0.00, 0.18)
p<0.0001 |
97%
(82–100%) |
| By age category | ||||||
| HIV-negative
partner <25 years old |
17.1/344.7 | 4.97 | 1/332.0 | 0.30 | 0.06 (0.01, 0.46)
p<0.0001 |
94%
(54–99%) |
| HIV-negative
partner ≥25 years old |
62.7/1357.4 | 4.62 | 3/1350.3 | 0.22 | 0.05 (0.02, 0.15)
p<0.0001 |
95%
(85–98%) |
| By HIV RNA
category |
||||||
| HIV-positive
partner HIV RNA ≥50,000 copies/ml |
39.3/674.0 | 5.84 | 2/707.3 | 0.28 | 0.05 (0.01, 0.20)
p<0.0001 |
95%
(80–99%) |
| HIV-positive
partner HIV RNA <50,000 copies/ml |
41.4/1024.9 | 4.04 | 2/975.0 | 0.21 | 0.05 (0.01, 0.21)
p<0.0001 |
95%
(79–99%) |
*The number of expected seroconversions and person-years do not sum precisely to the overall totals because each subgroup estimate is drawn from a separate bootstrapped counterfactual cohort model.
**per 100 person-years