In-host Modelling of COVID-19 in Humans

Abstract

1COVID-19 pandemic has underlined the impact of emergent pathogens as a major threat for human 2 health. The development of quantitative approaches to advance comprehension of the current outbreak 3 is urgently needed to tackle this severe disease. In this work, several mathematical models are proposed 4 to represent SARS-CoV-2 dynamics in infected patients. Considering different starting times of 5 infection, parameters sets that represent infectivity of SARS-CoV-2 are computed and compared with 6 other viral infections that can also cause pandemics. 7Based on the target cell model, SARS-CoV-2 infecting time between susceptible cells (mean of 30 8 days approximately) is much slower than those reported for Ebola (about 3 times slower) and influenza 9 (60 times slower). The within-host reproductive number for SARS-CoV-2 is consistent to the values of 10 influenza infection (1.7-5.35). The best model to fit the data was including immune responses, which 11 suggest a slow cell response peaking between 5 to 10 days post onset of symptoms. The model with 12 eclipse phase, time in a latent phase before becoming productively infected cells, was not supported. 13Interestingly, both, the target cell model and the model with immune responses, predict that virus may 14 replicate very slowly in the first days after infection, and it could be below detection levels during the 15 first 4 days post infection. A quantitative comprehension of SARS-CoV-2 dynamics and the estimation 16 of standard parameters of viral infections is the key contribution of this pioneering work.

Role of the Eye in Transmitting Human Coronavirus: What We Know and What We Do Not Know

“…However, CoVID-19 rarely results in notable symptoms of upper respiratory tract infection (e.g., rhinorrhea, sneezing, or sore throat), which are commonly manifested in SARS and MERS. Some CoVID-19 patients even manifest no apparent respiratory symptoms at onset, which never occurred in SARS and MERS (24)(25)(26). Mathematical models have revealed that the 2019-nCoV virus may replicate very slowly in the first days after infection and that it could be below detection levels during the first four days post infection (26).…”

“…Patients infected by 2019-nCoV, similar to SARS cases, mostly present with non-specific symptoms such as fever, dry cough, and dyspnoea, or, in some cases, no evident symptoms, at the early phase of the disease (9,16,(23)(24)(25)(26)(27)48). Hence, it is a challenging task for health care professionals in the northern hemisphere to distinguish early 2019-nCoV infection from influenza and other respiratory viral infections in the seasons of winter and spring when respiratory diseases frequently break out (48).…”

Characterization of SARS-CoV-2 dynamics in the host

“…Tocilizumab) and immunoglobulin therapy, among others. Recently, Hernandez-Vargas & Velasco-Hernandez, 2020 proposed different intra-host mathematical models (2 based on target cell-limited model, with and without latent phase, and another considering immune response) for 9 patients with COVID-19. Numerical results in Hernandez-Vargas & Velasco-Hernandez, 2020 showed intra-host reproductive number values consistent to influenza infection (1.7-5.35).…”

“…Although models in Hernandez-Vargas & Velasco-Hernandez, 2020 have been fitted to COVID-19 patients data, a control theoretical approach is needed to characterize the model dynamics. Even when the equilibrium states are known, a formal stability analysis is needed to understand the model behavior and, mainly, to design efficient control strategies.…”

The Good, The Bad and The Ugly: A Mathematical Model Investigates the Differing Outcomes Among CoVID-19 Patients

“…The viral load is one of the primary predictors of the disease progression in most infectious diseases. Mathematical models that track the viral kinetics in CoVID-19 patients have also been built recently 45 . However, very few models exist so far that incorporate the interactions of the virally infected cells with different types of immune responses in the body 28,46 .…”