tetano
Editor, Senior Moderator
PLoS One
. 2021 Oct 18;16(10):e0258084.
doi: 10.1371/journal.pone.0258084. eCollection 2021.
Mechanistic modelling of COVID-19 and the impact of lockdowns on a short-time scale
Danish A Ahmed[SUP] 1 [/SUP], Ali R Ansari[SUP] 1 [/SUP], Mudassar Imran[SUP] 1 [/SUP], Kamal Dingle[SUP] 1 [/SUP], Michael B Bonsall[SUP] 2 [/SUP]
Affiliations
Abstract
Background: To mitigate the spread of the COVID-19 coronavirus, some countries have adopted more stringent non-pharmaceutical interventions in contrast to those widely used. In addition to standard practices such as enforcing curfews, social distancing, and closure of non-essential service industries, other non-conventional policies also have been implemented, such as the total lockdown of fragmented regions, which are composed of sparsely and highly populated areas.
Methods: In this paper, we model the movement of a host population using a mechanistic approach based on random walks, which are either diffusive or super-diffusive. Infections are realised through a contact process, whereby a susceptible host is infected if in close spatial proximity of the infectious host with an assigned transmission probability. Our focus is on a short-time scale (∼ 3 days), which is the average time lag time before an infected individual becomes infectious.
Results: We find that the level of infection remains approximately constant with an increase in population diffusion, and also in the case of faster population dispersal (super-diffusion). Moreover, we demonstrate how the efficacy of imposing a lockdown depends heavily on how susceptible and infectious individuals are distributed over space.
Conclusion: Our results indicate that on a short-time scale, the type of movement behaviour does not play an important role in rising infection levels. Also, lock-down restrictions are ineffective if the population distribution is homogeneous. However, in the case of a heterogeneous population, lockdowns are effective if a large proportion of infectious carriers are distributed in sparsely populated sub-regions.
. 2021 Oct 18;16(10):e0258084.
doi: 10.1371/journal.pone.0258084. eCollection 2021.
Mechanistic modelling of COVID-19 and the impact of lockdowns on a short-time scale
Danish A Ahmed[SUP] 1 [/SUP], Ali R Ansari[SUP] 1 [/SUP], Mudassar Imran[SUP] 1 [/SUP], Kamal Dingle[SUP] 1 [/SUP], Michael B Bonsall[SUP] 2 [/SUP]
Affiliations
- PMID: 34662346
- DOI: 10.1371/journal.pone.0258084
Abstract
Background: To mitigate the spread of the COVID-19 coronavirus, some countries have adopted more stringent non-pharmaceutical interventions in contrast to those widely used. In addition to standard practices such as enforcing curfews, social distancing, and closure of non-essential service industries, other non-conventional policies also have been implemented, such as the total lockdown of fragmented regions, which are composed of sparsely and highly populated areas.
Methods: In this paper, we model the movement of a host population using a mechanistic approach based on random walks, which are either diffusive or super-diffusive. Infections are realised through a contact process, whereby a susceptible host is infected if in close spatial proximity of the infectious host with an assigned transmission probability. Our focus is on a short-time scale (∼ 3 days), which is the average time lag time before an infected individual becomes infectious.
Results: We find that the level of infection remains approximately constant with an increase in population diffusion, and also in the case of faster population dispersal (super-diffusion). Moreover, we demonstrate how the efficacy of imposing a lockdown depends heavily on how susceptible and infectious individuals are distributed over space.
Conclusion: Our results indicate that on a short-time scale, the type of movement behaviour does not play an important role in rising infection levels. Also, lock-down restrictions are ineffective if the population distribution is homogeneous. However, in the case of a heterogeneous population, lockdowns are effective if a large proportion of infectious carriers are distributed in sparsely populated sub-regions.