Zoonotic MERS-CoV transmission: modeling, backward bifurcation and
optimal control analysis
Abstract
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) can cause mild
to severe acute respiratory illness with a high mortality rate. As of
January 2020, more than 2,500 cases of MERS-CoV resulting in around 860
deaths were reported globally. In the absence of neither effective
treatment nor a ready-to-use vaccine, control measures can be derived
from mathematical models of disease epidemiology. In this manuscript, we
propose and analyze a compartmental model of zoonotic MERS-CoV
transmission with two co-circulating strains. The human population is
considered with eight compartments while the zoonotic camel population
consist of two compartments. The expression of basic reproduction
numbers are obtained for both single strain and two strain version of
the proposed model. We show that the disease-free equilibrium of the
system with single stain is globally asymptotically stable under some
parametric conditions. We also demonstrate that both models undergo
backward bifurcation phenomenon, which in turn indicates that only
keeping $R_0$ below unity may not ensure eradication. To the best of
the authors knowledge, backward bifurcation was not shown in a MERS-CoV
transmission model previously. Further, we perform normalized
sensitivity analysis of important model parameters with respect to basic
reproduction number of the proposed model. Furthermore, we perform
optimal control analysis on different combination interventions with
four components namely preventive measures such as use of masks,
isolation of strain-1 infected people, strain-2 infected people and
infected camels. Optimal control analysis suggests that combination of
preventive measures and isolation of infected camels will eventually
eradicate the disease from the community.