A Retrospective Assessment of HIV Prevalence in the Central Black Sea Region of Türkiye

Background: HIV has been a major global health issue since the 1980s. The proportions of diagnosed and undiagnosed infections are important indicators of HIV control. This study investigated the prevalence and characteristics of HIV based on blood samples from patients presenting for diagnosis and treatment at a tertiary healthcare hospital in the Central Black Sea Region over a four-year retrospective period. Methods: We retrospectively evaluated 271,367 samples submitted for anti-HIV serology testing for pre-operative screening or clinical suspicion between 2020 and 2023. HIV-1/2 antibodies and p24 antigen were screened using chemiluminescence microparticle immunoassay (CMIA), and reactive samples were confirmed by real-time RT-PCR. HIV RNA results and immunological parameters were also analyzed. Results: Among 271,367 samples, 694 were HIV-positive, yielding a prevalence of 0.25%. Of 2207 individuals tested for HIV RNA, 699 (31.7%) were positive. HIV RNA positivity was higher in men than women (35.5% vs. 18.6%). Absolute CD4+ T-cell counts were similar between genders, while the CD4/CD8 ratio was significantly higher in women. Both CD4+ T-cell counts and CD4/CD8 ratios increased significantly after three months of treatment. Conclusions: This study demonstrates a low but increasing HIV seroprevalence in the region, with a clear predominance among males and young adults. The findings also reflect effective viral suppression among treated patients and significant immunological recovery after therapy, providing important regional data to guide HIV monitoring and public health interventions.