The control of vector-borne disease epidemics

Area of Science:

• Epidemiology
• Mathematical Biology
• Vector-Borne Disease Dynamics

Background:

• The basic reproduction number (R(0)) is a key metric for endemicity in disease modeling.
• R(0) has limitations in capturing epidemic dynamics, particularly in models with endemic equilibria.
• Understanding transitory disease behavior is crucial for effective public health interventions.

Purpose of the Study:

• To introduce a new threshold index for epidemicity, E(0), based on reactivity.
• To differentiate epidemicity from endemicity and analyze their distinct drivers.
• To re-evaluate control strategies for vector-borne diseases using the novel E(0) index.

Main Methods:

• Derived the epidemicity index E(0) from the concept of reactivity.
• Applied E(0) to mathematical models of vector-borne diseases.
• Analyzed the influence of various parameters (e.g., transmission efficiency, vector-host ratio, incubation period) on E(0) and R(0).

Main Results:

• E(0) quantifies the maximum new infections from an individual at disease-free equilibrium, capturing transitory epidemic potential.
• Transmission efficiency and vector-host ratio significantly impact epidemicity (E(0)) more than endemicity (R(0)).
• Parasite-modified vector behavior, feeding bias, and host attractiveness strongly influence transitory epidemics.

Conclusions:

• The E(0) index provides a valuable tool for understanding and predicting epidemic potential, complementing R(0).
• Vector-borne disease control strategies may need re-evaluation based on factors influencing epidemicity.
• The E(0) framework is potentially applicable to diverse disease transmission models beyond vector-borne diseases.