PREDICTING THE EVOLUTION OF COVID-19 IN PORTUGAL USING AN ADAPTED SIR MODEL PREVIOUSLY USED IN SOUTH KOREA FOR THE MERS OUTBREAK

Teles, Pedro

Since original reports in Wuhan, China, the new coronavirus covid-19 has spread very quickly worldwide, leading the World Health Organization (WHO) to declare a state of pandemic. Moreover, as of the 13th of March 2020, the WHO has announced that the European continent is now the main centre of the pandemic. Many European governments have already implemented harsh measures to attempt to contain the spread of the virus. In Portugal, there are, as of the 20th of March 2020, 1020 confirmed cases. One of the questions many policy makers, and governments are asking themselves is how the spread is going to evolve in time. A timely idea of the amount of cases that will exist in a near future can allow governments and policy makers to act accordingly. In this study, I applied an adapted SIR model previously used in South Korea to model the MERS outbreak, which is also caused by a coronavirus, to estimate the evolution of the curve of active cases in the case of the Portuguese situation. As some of the parameters were unknown, and the data for Portugal is still scarce, given that the outbreak started later (first case on the 2nd of March) I used Italian data (first reported case in Italy on the 31st of January) to predict them. I then construct two or three different scenarios for the evolution of covid-19 in Portugal, considering both the effectiveness of the mitigation measurements implemented by the government, and the self-protective measures taken by the population, as explained in the South Korean model. In the out of control scenario, the number of active cases could reach as much as ~40,000 people by the beginning of April. If measures are appropriately taken this number can be reduced to about 800 cases. In case that some measures are taken, but their implementation is not done appropriately, the active cases could reach circa 7,000 people. The actual figures probably lie between the interval (~800-7,000) and the peak will be reached between 9th and the 20nd of April 2020. Without control and self-protective measures, this model predicts that the figures of active cases of SARS-covid-2 would reach a staggering ~40,000 people It shows the importance of control and self-protecting measure to bring down the number of affected people by following the recommendations of the WHO and health authorities. With the appropriate measures, this number can be brought down to ~800-7,000 people. Hopefully that will be the case not just in Portugal, but in the rest of the World.