Data generated for "A model exploration of carrier and movement transmission as potential explanatory causes for the persistence of foot-and-mouth disease in endemic regions."

This dataset is used in a submitted paper entitled "A model exploration of carrier and movement transmission as potential explanatory causes for the persistence of foot-and-mouth disease in endemic regions."

Abstract:
Foot-and-Mouth Disease (FMD) is a virulent and economically important disease of livestock, still endemic in many areas of Asia and Sub-Saharan Africa. Transmission from persistently infected livestock, also known as carriers, has been proposed as a mechanism to support the persistence of FMD in endemic regions. However whether carrier livestock can infect susceptible animals is controversial; recovered virus is infectious and there are claims of field transmission, but it remains undemonstrated experimentally. Alternate hypotheses for persistence include the movement of livestock within and between regions, and fomite contamination of the environment. Using a stochastic compartmental Ordinary Differential Equation (ODE) model, we investigate the minimum rates of carrier transmission necessary to contribute to the maintenance of FMD in a region, and compare this to the alternate mechanism of persistence through cattle shipments. We find that carrier transmission can theoretically support persistence even at transmission rates much lower than the highest realistic rates previously proposed, and that the parameters with the most effect on the feasibility of carrier-mediated persistence are the average duration of both the carrier phase and natural immunity. However, shipment-mediated persistence remains a viable alternate mechanism for persistence without carrier transmission.

Methods Overview:
Using a compartmental metapopulation ODE model with detailed agricultural data, we simulated carrier transmission and shipment transmission with a range of different parameters. Each parameter set was simulated 100 times for 5 years, and the proportion of these simulations where FMD persisted until the end of the simulation was taken as a proxy for the probability of persistence given those parameters.