Fractional order modeling of hepatitis C transmission dynamics with physics-informed neural network solutions

BMC Infect Dis. 2026 Feb 24;26(1):457. doi: 10.1186/s12879-026-12792-y.

Abstract

This study develops a fractional-order mathematical model for Hepatitis C Virus (HCV) transmission using a six-compartment framework and the Caputo–Fabrizio derivative. The operator’s exponential kernel captures essential short-term memory effects in acute infection and treatment response, a key advancement over classical integer-order models. We establish the model’s well-posedness through rigorous positivity, boundedness, existence-uniqueness, and stability analyses. The basic reproduction number formula image confirms epidemic potential, with sensitivity analysis identifying acute transmission (β2) as the dominant driver, accounting for over 51% of new infections—a critical public health insight. Fractional-order simulations demonstrate that increased memory effects (lower fractional order) delay and flatten outbreak waves, underscoring the importance of sustained interventions. A novel Physics-Informed Neural Network (PINN) is implemented to solve the coupled fractional system. The PINN achieves high predictive accuracy (formula image, low RMSE) for Susceptible, Exposed, Acute, and Quit Treatment compartments, though performance is moderate for the Chronic stage (formula image, reflecting its more complex, heterogeneous dynamics. The PINN’s success offers a mesh-free, computationally efficient alternative to traditional numerical schemes for complex epidemiological systems. This work’s primary contribution is the first integration of a Caputo–Fabrizio HCV model with a PINN solver, creating a hybrid mechanistic-data-driven framework. The results provide actionable strategies: prioritizing acute-phase control and implementing long-term, memory-aware public health measures. The model serves as a validated tool for optimizing HCV elimination strategies, particularly in resource-limited settings, while highlighting directions for future refinement, including integration with real-world clinical data.

Keywords: Caputo-Fabrizio; Existence and uniqueness using fixed point theory; Machine learning; Newton interpolation in numerical scheme; Physics informed neural network; Prediction; Time series; Ulam-Hyers stability.