Transmission dynamics and optimal control of stage-structured HLB model

Area of Science:

• Plant Pathology
• Epidemiology
• Mathematical Modeling

Background:

• Citrus Huanglongbing (HLB) is a devastating, quarantine-regulated disease impacting global citrus production.
• HLB is transmitted by vectors, necessitating effective control strategies.

Purpose of the Study:

• To develop and analyze a vector-borne mathematical model for citrus HLB transmission.
• To investigate the efficacy of an integrated strategy for controlling HLB spread.
• To determine the optimal integrated strategy using optimal control theory.

Main Methods:

• Formulation of a stage-structured, vector-borne epidemiological model for HLB.
• Calculation of the basic reproductive number (R0) to assess disease persistence or eradication thresholds.
• Application of optimal control theory to derive an optimal integrated management strategy.
• Simulation of the model using real-world data from "Yuan Orchard" in Ganzhou City, China.

Main Results:

• The model confirms that HLB eradication is achievable when R0 < 1, while R0 > 1 indicates disease persistence.
• An optimal integrated strategy was mathematically derived to manage HLB spread.
• Numerical simulations validated the model's predictions using field data.

Conclusions:

• The developed mathematical model provides a robust framework for understanding and managing citrus HLB transmission.
• Integrated control strategies, guided by epidemiological modeling, are crucial for mitigating the impact of HLB on citrus production.
• The study highlights the importance of R0 as a key indicator for disease control success.