Key result
Carrier transmission can theoretically support foot-and-mouth disease persistence at very low transmission rates, depending heavily on the duration of the carrier phase and natural immunity.
Why the study?
Whether persistently infected carrier livestock can infect susceptible animals and sustain foot-and-mouth disease persistence in endemic regions remains controversial and experimentally undemonstrated.
Mathematical modeling suggests that both carrier transmission and livestock shipments are viable mechanisms for the persistence of foot-and-mouth disease in endemic regions.
Carrier transmission of FMD remains unproven; leaves open its role in endemic persistence and requires controlled studies.
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.
No takes yet. Share an insight, caveat, or question.
Guyver‐Fletcher et al. (2021) studied Foot-and-mouth disease. Carrier transmission and cattle shipments was evaluated on Minimum rates of carrier transmission necessary to contribute to the maintenance of FMD. Carrier transmission can theoretically support foot-and-mouth disease persistence at very low transmission rates, depending heavily on the duration of the carrier phase and natural immunity.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: