In order to assess the effectiveness of response strategies of avoiding large gatherings or crowded areas and to predict the spread of COVID-19 infections in Japan , Japanese scientists developed a stochastic transmission model by extending the Susceptible-Infected-Removed (SIR) epidemiological model with an additional modeling of the individual action on whether to stay away from the crowded areas.
They divided the population into three compartments: Susceptible, Infected, Removed
Susceptible transitions to Infected every hour with a probability determined by the ratio of Infected and the congestion of area. The total area consists of three zones crowded zone, mid zone and uncrowded zone, with different infection probabilities characterized by the number of people gathered there.
The time for each people to spend in the crowded zone is curtailed by 0, 2, 4, 6, 7, and 8 hours, and the time spent in mid zone is extended accordingly.
Simulation showed that the number of Infected and Removed will increase rapidly if there is no reduction of the time spent in crowded zone.
On the other hand, the stagnant growth of Infected can be observed when the time spent in the crowded zone is reduced to 4 hours, and the growth number of Infected will decrease and the spread of the infection will subside gradually if the time spent in the crowded zone is further cut to 2 hours
Scientist conclusions are that infection spread will be gradually contained by reducing the time spent in the crowded zone to less than 4 hours.
So this research confirm that banning peoples gathering made by most countries are excellent strategy to stop the spread of COVID-19 infections
Full research is published yesterday in “BioScience Trends” and you can find full research on this link