Bulletin of Mathematical Biology (2022) 84:41
https://doi.org/10.1007/s11538-022-01001-x
ORIGINAL ARTICLE
A Comparison of Deterministic and Stochastic
Plant-Vector-Virus Models Based on Probability of Disease
Extinction and Outbreak
Sunil Maity
1
· Partha Sarathi Mandal
1
Received: 3 September 2021 / Accepted: 24 January 2022
© The Author(s), under exclusive licence to Society for Mathematical Biology 2022
Abstract
In this investigation, we formulate and analyse a stochastic epidemic model using the
continuous-time Markov chain model for the propagation of a vector-borne cassava
mosaic disease in a single population. The stochastic model is based upon a pre-existing
deterministic plant-vector-virus model. To see how demographic stochasticity affects
the vector-borne cassava mosaic disease dynamics, we compare the disease dynamics
of both deterministic and stochastic models through disease extinction process. The
probability of disease extinction and therefore the major outbreak are estimated analyt-
ically using the multitype Galton–Watson branching process (GWbp) approximation.
Also, we have found the approximate probabilities of disease extinction numerically
based on 30000 sample paths, and it is shown to be good estimate with the calcu-
lated probabilities from GWbp approximation. In particular, it is observed that there
is a very high probability of disease extinction when the disease is introduced via the
infected vectors rather than through infected plants.
Keywords Cassava mosaic disease · Stochastic model · Markov chain · Multitype
branching process · Probability of extinction
1 Introduction
Plants are essential for both humans and many other creatures. They are sources of
food, medicine, clothing fibre, and housing materials. They are an essential part of
maintaining a healthy ecosystem. Plant viruses are one of the most important obstacles
to modern agriculture, especially in lesser-developed countries, and are often spread by
insects (Hebert and Allen 2016; Jeger et al. 2004; Thresh 1983; Waterworth and Hadidi
1998; Fereres et al. 2000). Begomoviruses, which are carried by the whitefly Bemisia
B Partha Sarathi Mandal
parthas@nitp.ac.in
1
Department of Mathematics, NIT Patna, Patna, Bihar, India
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