Mathematical Modeling of Bacteriophage Lytic Cycle Dynamics: Insights from Experimental Data and Delay Differential Equations

Bacteriophages (phages) play a crucial role in bacterial population control, with applications in phage therapy and biotechnology. This study analyzes experimental data on phage cultivation in a bacterial culture and develops a delay differential equation (DDE) model to describe the dynamics. The model incorporates bacterial logistic growth, phage adsorption, a latent period, and burst release. Parameters were fitted to a subset of data excluding early outliers, yielding a high goodness of fit (R² = 0.92). Key findings include a latent period of approximately 115 minutes and a burst size of about 85, consistent with T4-like phages infecting Escherichia coli under suboptimal growth conditions. Empirical correlations between optical density (OD) and titres enable rapid predictions, offering a simple alternative to time-consuming microbiological assays. Comparisons to the literature validate the model’s biological realism and highlight trade-offs in phage life-history traits.