Publication related to RSI or an RSI staff member
Modeling the effect of lockdown timing as a COVID-19 control measure in countries with differing social contacts.
Authors
- Oraby, Tamer, Oraby T, School of Mathematical and Statistical Sciences, The University of Texas Rio Grande Valley, Edinburg, TX, 78539, USA. tamer.oraby@utrgv.edu.
- Tyshenko, Michael G, Tyshenko MG, McLaughlin Centre for Population Health Risk Assessment, Faculty of Medicine, University of Ottawa, Ottawa, ON, K1N 6N5, Canada.
- Maldonado, Jose Campo, Maldonado JC, School of Medicine, The University of Texas Rio Grande Valley, Edinburg, TX, 78539, USA.
- Vatcheva, Kristina, Vatcheva K, School of Mathematical and Statistical Sciences, The University of Texas Rio Grande Valley, Edinburg, TX, 78539, USA.
- Elsaadany, Susie, Elsaadany S, Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.
- Alali, Walid Q, Alali WQ, Department of Epidemiology and Biostatistics, Faculty of Public Health, Kuwait University, 13110, Safat, Kuwait.
- Longenecker, Joseph C, Longenecker JC, Department of Public Health Practice, Faculty of Public Health, Kuwait University, 13110, Safat, Kuwait.
- Al-Zoughool, Mustafa, Al-Zoughool M, Department of Environmental and Occupational Health, Faculty of Public Health, Kuwait University, 13110, Safat, Kuwait.
The application, timing, and duration of lockdown strategies during a pandemic remain poorly quantified with regards to expected public health outcomes. Previous projection models have reached conflicting conclusions about the effect of complete lockdowns on COVID-19 outcomes. We developed a stochastic continuous-time Markov chain (CTMC) model with eight states including the environment (SEAMHQRD-V), and derived a formula for the basic reproduction number, R(0), for that model. Applying the [Formula: see text] formula as a function in previously-published social contact matrices from 152 countries, we produced the distribution and four categories of possible [Formula: see text] for the 152 countries and chose one country from each quarter as a representative for four social contact categories (Canada, China, Mexico, and Niger). The model was then used to predict the effects of lockdown timing in those four categories through the representative countries. The analysis for the effect of a lockdown was performed without the influence of the other control measures, like social distancing and mask wearing, to quantify its absolute effect. Hypothetical lockdown timing was shown to be the critical parameter in ameliorating pandemic peak incidence. More importantly, we found that well-timed lockdowns can split the peak of hospitalizations into two smaller distant peaks while extending the overall pandemic duration. The timing of lockdowns reveals that a "tunneling" effect on incidence can be achieved to bypass the peak and prevent pandemic caseloads from exceeding hospital capacity.
