Mathematical epidemiology of rice dwarf virus transmitted by green rice leafhoppers: a differential equation model.
Abstract
Both the number of rice hills (clumps of tillering stalks from planted seedlings) and the density of vectors were divided into 3 categories: healthy, latent infected and infectious. The rate of virus transmission to rice hills was given by the product of virus transmission efficiency, number of healthy hills and density of infectious vectors (Nephotettix cincticeps). The rate of acquisition feeding of virus by vectors was given by the product of the efficiency of acquisition feeding, number of infectious hills and density of healthy vectors. The population growth of vectors was assumed to follow a logistic equation. The rate of transovarial transmission of the virus by the vector was included in the model giving a smaller birth rate for infectious vectors than for healthy ones. Parameter values were determined using actual data from indoor experiments and outdoor studies.
The predictions of the model were validated with data on the percentages of vectors and rice hills that were infected.