Sex work or male-with-male sexual activity and the risks of HIV and hepatitis C acquisition among people who inject drugs: a global systematic review and meta-analysis.
J. Dawe, A. Trickey, et al. • EClinicalMedicine • 2026
PWID who also engage in sex work or male-with-male sex were found to have higher HIV or HCV acquisition risks, and future research should aim to understand the mechanisms driving these associations.
Key Findings
Results
The review included 57 studies comprising 164 estimates of the association between sex work or male-with-male sex and HIV or HCV incidence among people who inject drugs.
MEDLINE, Embase, and PsycINFO were searched for studies among PWID published from 01/01/2000.
Eligible studies estimated incidence by longitudinally re-testing people at risk or by using assays for recent infection.
Authors were also contacted for unpublished estimates.
Estimates were pooled using random-effects meta-analysis; the review is registered with Prospero (CRD42020220884).
Results
Among men who inject drugs, recent male-with-male sex was associated with higher HIV acquisition.
Pooled incidence rate ratio (IRR) 2.35 (95% CI: 1.51-3.66).
Heterogeneity was moderate (I2: 51%).
Results
Among men who inject drugs, recent male-with-male sex was not clearly associated with HCV acquisition.
Pooled IRR 1.28 (95% CI: 0.95-1.72).
I2: 21%.
Results
Recent sex work was associated with higher HIV and HCV acquisition risk among all PWID.
HIV: IRR 1.72 (95% CI: 1.30-2.28; I2: 65%).
HCV: IRR 1.59 (95% CI: 1.29-1.96; I2: 60%).
Results
When stratified by sex, recent sex work was associated with HIV acquisition among women but not men.
Women: IRR 2.30 (95% CI: 1.44-3.68; I2: 68%).
Men: IRR 1.43 (95% CI: 0.92-2.22; I2: 51%).
Results
When stratified by sex, recent sex work was associated with HCV acquisition among men but not women.
Men: IRR 1.51 (95% CI: 1.22-1.87; I2: 0%).
Women: IRR 1.26 (95% CI: 0.90-1.77; I2: 55%).
Results
For lifetime behaviours, only male-with-male sex was associated with HIV acquisition.
Lifetime male-with-male sex and HIV: IRR 2.44 (95% CI: 1.18-5.02), with considerable heterogeneity (I2 = 87%).
Other lifetime behaviour associations were not reported as significant in the abstract.
Results
Egger's tests did not provide evidence of asymmetry bias for the pooled estimates, but heterogeneity was considerable for many outcomes.
I2 values ranged from 0% to 87% across pooled estimates.
Publication asymmetry was assessed using Egger's test.
What This Means
This study pooled results from 57 studies worldwide to see whether people who inject drugs and who also do sex work or, among men, have sex with men are more likely to newly acquire HIV or hepatitis C. Overall, they were. Men who had recent sex with men had about 2.4 times the rate of new HIV infection, but no clear difference in hepatitis C. Recent sex work was linked to about 1.7 times the HIV rate and 1.6 times the hepatitis C rate among all people who inject drugs.
The patterns differed by sex. Sex work was linked to higher HIV risk among women but not clearly among men, and to higher hepatitis C risk among men but not clearly among women. Looking at lifetime behaviour rather than recent behaviour, only male-with-male sex was linked to higher HIV risk.
These findings suggest that people who inject drugs and also engage in these sexual behaviours may need HIV and hepatitis C prevention and care that address both injecting and sexual risks. The studies varied considerably in their results, and the review could not explain why these associations exist, so the authors call for more research on the underlying mechanisms.
J. Dawe, A. Trickey, Josephine G. Walker, L. Barrass, B. Njiro, Bidisha Kundu, et al.. (2026). Sex work or male-with-male sexual activity and the risks of HIV and hepatitis C acquisition among people who inject drugs: a global systematic review and meta-analysis.. EClinicalMedicine. https://doi.org/10.1016/j.eclinm.2026.104268