Understanding the Decline of HIV Incidence: Insights from Structural Equation Modeling of Social and Biological Factors

Oluwasegun Olawale Benjamin; Gbenga Wilfred Akinola; Gloria Nnadwa Alhassan

doi:10.18521/ktd.1732834

Research Article

Understanding the Decline of HIV Incidence: Insights from Structural Equation Modeling of Social and Biological Factors

Year 2026, Volume: 18 Issue: 1, 6 - 16, 24.03.2026

Oluwasegun Olawale Benjamin Gbenga Wilfred Akinola Gloria Nnadwa Alhassan

https://doi.org/10.18521/ktd.1732834

https://izlik.org/JA84SX46GH

Abstract

Aim: Nigeria ranks among the countries with a high burden of Human Immunodeficiency Virus (HIV), though national incidence and prevalence have declined in recent years. Ekiti State has consistently shown lower HIV rates compared to other regions, but the specific drivers of this perceived decline remain underexplored. This study aimed to identify the key social, behavioral, and biological factors contributing to the declining HIV incidence in Ekiti State, Nigeria, using Structural Equation Modelling (SEM).
Material and Methods: A cross-sectional survey was conducted from January to March 2023 among 448 knowledgeable informants (health professionals from state and local AIDS control agencies, medical personnel, and students). Data on perceived HIV incidence and contributing factors were collected via a structured questionnaire. Confirmatory Factor Analysis and SEM were performed using AMOS software to test hypothesized paths from latent constructs (social factors, e.g., condom promotion and education campaigns; sexual behavioral factors, e.g., reductions in concurrent partners; biological factors, e.g., antiretroviral therapy access and STI reductions) to perceived declining incidence.
Results: Social (β = 0.356, p < 0.001) and biological (β = 0.309, p < 0.001) factors were significantly associated with perceived decline in HIV incidence, while sexual behavioral factors were not (β = 0.019, p > 0.05). The model demonstrated good fit (CFI = 0.987, RMSEA = 0.030, χ²/df = 1.389).
Conclusion: The perceived reduction in HIV incidence in Ekiti State is primarily associated with social and biological interventions. These findings highlight the value of integrated public health approaches and support efforts toward Sustainable Development Goal 3 (Good health and well-being).

Keywords

Human immunodeficiency virüs , structural equation modeling , perceived decline , social factors , biological factors , good health and well-being

Ethical Statement

This study was conducted in full compliance with the ethical principles outlined in the Declaration of Helsinki. Ethical approval was obtained from the Ethical and Legal Review Committee (ELRC) of the Federal University Oye-Ekiti, Nigeria, with approval number ELRC/SOS/002. All participants involved in the study provided written informed consent prior to their inclusion. The research team ensured that participant confidentiality, data protection, and ethical conduct were upheld throughout the research process, in line with the university’s research ethics policy.

Supporting Institution

We hereby declare that there is no form of funding received for this study.

Project Number

6755

Thanks

The authors do not wish to acknowledge any individual or institution.

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