Background: Herpes simplex virus type-2 (HSV-2) and human papillomavirus (HPV) are common
sexually transmitted infections (STIs) among fishing communities and are associated with high
HIV prevalence in this underserved population. However, there is limited knowledge on HIV incidence
among fishermen. This study aimed at determining prevalence, incidence and risk factors
associated with HIV infection among fishermen in Kisumu Kenya. Methods: Three hundred fishermen
were evaluated for baseline HIV, HSV-2, HPV infection and a structured questionnaire
administered. HIV incidence was assessed after 12 months among those initially HIV negative. HIV
incidence rate in person-years and prevalence were estimated. Multivariate logistic regression
was used to determine factors independently associated with HIV acquisition. Results: HIV prevalence
was 23.3% (95% CI: 18.5 - 28.1). Risk factors for baseline HIV prevalence were older age
(aOR = 2.13; 95% CI: 1.25 - 5.07), history of STI (aOR 4.21; 95% CI: 2.07 - 9.34), baseline HPV infection
(aOR 2.13; 95% CI: 1.05 - 4.77), number of lifetime sexual partners (>5) aOR = 5.76 (95% CI:
1.41 - 13.57) and transactional sex (aOR = 10.98; 95% CI: 1.86 - 19.34). Condom uses with new
sexual partner (aOR 0.21, 95% CI: 0.08 - 0.55) and during most recent sexual act (aOR 0.09, 95% CI:
0.03 - 0.61), were negatively associated with HIV prevalence. HIV incidence was 4.2 (95% CI = 1.3 -
7.1) per 100 person-years with being single (aIRR = 8.32; 95% CI: 1.27 - 54.67) as an independent
risk factor. Condom use with new sexual partner (aIRR = 0.11; 95% CI: 0.01 - 0.89) and recent sex
with wife/regular girlfriend (compared to sex worker/casual partner; aIRR = 0.03; 95% CI: 0.01 -
0.35) were associated with reduced risk of HIV acquisition. Conclusion: Inconsistent condom use
and transactional/casual sexual partnerships were the main high-risk sexual behaviors in addition to marital status explaining the high HIV acquisition rate among fishermen. Intensified safer
sex promotion is urgently needed in this subpopulation to avert new HIV infections.