HIV-1 late diagnosis in Cabo Verde: associated factors and implications for preventive strategies.

Background: Late diagnosis of HIV infection remains a major public health challenge, associated with higher morbidity and mortality, ongoing transmission, opportunistic infections, and higher healthcare costs. Despite free access to HIV-1 testing and antiretroviral therapy in Cabo Verde, the prevalence and determinants of late HIV diagnosis remain poorly characterised. Therefore, this study aimed to assess the prevalence of late HIV diagnosis and identify associated factors among newly diagnosed, treatment-naïve individuals with HIV-1 in Cabo Verde. Methods: A cross-sectional study combining interview - based data with retrospective extraction of clinical data was conducted among 135 newly diagnosed, treatment - naïve individuals between 2018 and 2019 across four islands of Santiago, Fogo, São Vicente, and Boavista. Late HIV diagnosis was defined as CD4+ < 350 cells/µL at diagnosis or the presence of an AIDS-defining condition. Sociodemographic and clinical data were collected, and viral genetic diversity was assessed through nucleotide ambiguity analysis. Associations with late HIV diagnosis were evaluated using univariable and multivariable logistic regression, presented as odds ratios (OR) and 95% confidence intervals (CI). Results: Overall, 56.3% (76/135) of individuals were classified as having late HIV diagnosis. In multivariable analysis, being single (aOR: 2.79; 95% CI: 1.13-6.92; Conclusions: HIV-1 late diagnosis remains highly prevalent in Cabo Verde and is associated with single marital status and higher viral load. These findings highlight persistent gaps in early HIV testing and timely linkage to care. Strengthening targeted testing strategies is essential to improve clinical outcomes and reduce HIV transmission, in line with the UNAIDS 95-95-95 targets.