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Quantifying Delay in First Contact With HIV Programs Among Young Women Engaged in Sex Work in Mombasa, Kenya: A
Huiting Ma1, Kristy C Y Yiu1, Linwei Wang1
1MAP Centre for Urban Health Solutions, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada.
Background:
Young women engaged in sex work (YSW) experience a disproportionately high burden of HIV, yet most HIV programs for sex workers are not designed to reach YSW.
Methods:
Longitudinal data from the start of sex work are infeasible, but cross-sectional surveys may help identify "contact gaps." We used data from the 2015 Transitions Study, a cross-sectional survey of sexually active women aged 14-24 who self-identified as a sex worker in Mombasa, Kenya. We created a virtual cohort using self-reported event timing described relative to the survey date. We quantified the time from self-identification as sex worker to the initial program contact ("contact gap") and employed time-to-event analyses to estimate and characterize factors associated with the rate of program contact.
Results:
Of 392 YSW included in the time-to-event analyses, only 47 (12%) reported program contact, with a median time of 12 months (interquartile range: 2‒24). The rate of program contact per 100 person-months was 0.52 [95% confidence interval (CI): 0.38 to 0.68], and when applied to the estimated population size of YSW in Mombasa, the minimum contact gap was 11,532 person-years. A shorter contact gap was associated with older age when first negotiated money for sex [adjusted hazard ratio: 1.2 (95% CI: 1.0 to 1.5)] and perceiving earning money through sex work as easy [11.5 (2.8 to 47.7)].
Conclusions:
A large contact gap highlights the need to reshape HIV prevention services for YSW across their life course. Despite limitations, cross-sectional data could help estimate the contact gap and support program monitoring and evaluation.
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