Within a short period of time, COVID-19 grew into a world-wide pandemic. Transmission by pre-symptomatic and asymptomatic viral carriers rendered intervention and containment of the disease extremely challenging. Based on reported infection case studies, we construct an epidemiological model that focuses on transmission around the symptom onset. The model is calibrated against incubation period and pairwise transmission statistics during the initial outbreaks of the pandemic outside Wuhan with minimal non-pharmaceutical interventions. Mathematical treatment of the model yields explicit expressions for the size of latent and pre-symptomatic subpopulations during the exponential growth phase, with the local epidemic growth rate as input. We then explore reduction of the basic reproduction number R 0 through specific transmission control measures such as contact tracing, testing, social distancing, wearing masks and sheltering in place. When these measures are implemented in combination, their effects on R 0 multiply. We also compare our model behaviour to the first wave of the COVID-19 spreading in various affected regions and highlight generic and less generic features of the pandemic development. Transmission by pre-symptomatic and asymptomatic viral carriers makes intervention and containment of the COVID-19 extremely challenging. Here, the authors construct an epidemiological model that focuses on transmission around the symptom onset, exploring specific transmission control measures.
【저자키워드】 viral infection, Biological physics, Population dynamics, Statistical physics, 【초록키워드】 COVID-19, Treatment, pandemic, social distancing, Infection, Contact tracing, Intervention, Local, Transmission, Epidemic, Region, Measures, Asymptomatic, outbreak, pre-symptomatic, Wuhan, Incubation period, basic reproduction number, epidemiological, First wave, expression, Combination, exponential growth phase, reduction, symptom onset, growth, measure, subpopulation, carrier, Effect, feature, highlight, initial, affected, reported, the disease, less, calibrated, explicit, wearing mask, 【제목키워드】 COVID-19 pandemic, Intervention, Transmission, symptom onset,