Mathematical Modelling to Assess the Impact of Lockdown on COVID-19 Transmission in India: Model Development and Validation

Abstract

Background The World Health Organization has declared the novel coronavirus disease (COVID-19) to be a public health emergency; at present, India is facing a major threat of community spread. We developed a mathematical model for investigating and predicting the effects of lockdown on future COVID-19 cases with a specific focus on India. Objective The objective of this work was to develop and validate a mathematical model and to assess the impact of various lockdown scenarios on COVID-19 transmission in India. Methods A model consisting of a framework of ordinary differential equations was developed by incorporating the actual reported cases in 14 countries. After validation, the model was applied to predict COVID-19 transmission in India for different intervention scenarios in terms of lockdown for 4, 14, 21, 42, and 60 days. We also assessed the situations of enhanced exposure due to aggregation of individuals in transit stations and shopping malls before the lockdown. Results The developed model is efficient in predicting the number of COVID-19 cases compared to the actual reported cases in 14 countries. For India, the model predicted marked reductions in cases for the intervention periods of 14 and 21 days of lockdown and significant reduction for 42 days of lockdown. Such intervention exceeding 42 days does not result in measurable improvement. Finally, for the scenario of “panic shopping” or situations where there is a sudden increase in the factors leading to higher exposure to infection, the model predicted an exponential transmission, resulting in failure of the considered intervention strategy. Conclusions Implementation of a strict lockdown for a period of at least 21 days is expected to reduce the transmission of COVID-19. However, a further extension of up to 42 days is required to significantly reduce the transmission of COVID-19 in India. Any relaxation in the lockdown may lead to exponential transmission, resulting in a heavy burden on the health care system in the country.

The effect of lockdown on the outcomes of COVID-19 in Spain: An ecological study

“…A study that evaluated pandemic data in Spain, between February 24 and April 5, 2020, identified that physical distancing measures were effective to control the spreading of the disease[ 25 , 26 ], especially when correctly enforced and with adequate duration[ 27 ]. Scientific literature also reports similar results to those presented herein, in countries that effectively controlled the pandemic by adopting these restrictive measures: Singapore, South Korea, and the territory of Hong Kong[ 3 , 7 , 9 ], as well as China[ 28 , 29 ].…”

Investigation of early epidemiological signals of COVID-19 in India using outbreak surveillance data

“…The model had predicted that implementation of a strict lockdown for a period of 21 days would reduce the transmission of COVID-19 and suggested that further extension of up to 42 days would be required to significantly reduce the transmission of COVID-19 in India. 29 Although the public health interventions may have been effective in controlling the community transmission in India, it is still widely believed that there is limited testing in India, which could result in under-reporting or misdiagnosis of the exact number of cases. 30 In order to combat this issue, India has scaled up testing by increasing the number of laboratories and by providing free testing for COVID-19.…”

Stochastic approach to study control strategies of Covid-19 pandemic in India

“…Likewise, there have been many studies on the Covid-19 pandemic in India using various mathematical models. However, most of these studies adopt deterministic methods [10][11][12][13][14][15][16][17][18][19][20][21]. On the other hand, to capture the qualitative as well as quantitative real dynamic situations to intervene in disease outbreaks, a stochastic approach needs to be employed.…”