Factors associated with vaccination completion and retention among HIV negative female sex workers enrolled in a simulated vaccine efficacy trial in Kampala, Uganda

• Published in: BMC infectious diseases Vol. 19; no. 1; p. 725
• Main Authors: Mayanja, Yunia, Abaasa, Andrew, Namale, Gertrude, Asiki, Gershim, Price, Matthew A, Kamali, Anatoli
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 16.08.2019; BioMed Central; BMC
• Subjects: Adolescent; Adult; AIDS Vaccines; Clinical trials; Condoms; Demographic aspects; Emtricitabine; Female; Female sex workers; Health aspects; Hepatitis B; Hepatitis B vaccines; Hepatitis B Vaccines - therapeutic use; HIV; HIV infections; HIV Infections - prevention & control; HIV prevention trials; HIV Seronegativity; Humans; Medical research; Medicin och hälsovetenskap; Pregnant women; Prevention; Prospective Studies; Prostitutes; Retention; Risk factors; Safe Sex; Sex oriented businesses; Sex Workers; Sexual Partners; Sub Saharan Africa; Testing; Uganda; Vaccination; Vaccination - methods; Vaccination - statistics & numerical data; Vaccination completion; Working women; Uganda; Female sex workers; HIV prevention trials; Retention; Sub Saharan Africa; Vaccination completion
• ISSN: 1471-2334; 1471-2334
• DOI: 10.1186/s12879-019-4328-1

Female sex workers (FSWs) at substantial risk of HIV are potentially a suitable group for HIV prevention trials including vaccine trials. Few HIV vaccine preparatory studies have been conducted among FSWs in Sub-Saharan Africa (SSA); data are therefore limited on acceptability of vaccine trial procedures. We determined vaccination completion and one-year retention among FSWs in Kampala, Uganda. We conducted a prospective study that simulated a vaccine efficacy trial among HIV negative FSWs (18-49 years). Hepatitis B vaccine (Engerix B) was used to mimic an HIV vaccine product. Volunteers received 1 ml intramuscular injection at 0, 1 and 6 months, and made additional visits (3 days post-vaccination and months 3, 9 and 12). They were censored at that visit if diagnosed as HIV positive or pregnant. We collected socio-demographic, behavioral and clinical data at baseline, 6 and 12 months and fitted Poisson regression models with robust standard error to find factors associated with vaccination completion and retention. We enrolled 290 volunteers (median age 27 years) of whom 230 reached a study end-point as follows: 7 became HIV infected, 11 became pregnant and 212 completed both the vaccination schedule and 12-month visit giving a retention of 77.9% (212/272). Vaccination completion was 82.4%. Non-retention at 1 year was more likely among those reporting symptoms of genital ulcer disease (GUD) in the past 3 months (IRR 1.90; 95% CI 1.09-3.32) and those < 35 years; (IRR 6.59; 95% CI 2.11-20.57). Non-completion of the vaccination schedule was associated with being < 35 years (IRR 13.10; 95% CI 1.89-90.92, reporting GUD symptoms (IRR 3.02; 95% CI 1.71-5.33) and reporting consistent condom use with new sexual partners (IRR 2.57; 95% CI 1.10-6.07). FSWs are at substantial risk of HIV infection and yet willing to participate in HIV vaccine and prevention research; young FSWs should be empowered, and those reporting GUD symptoms need close follow up to improve participation in future HIV vaccine trials.