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arXiv · 2003.10047

Predicting the evolution Of SARS-Covid-2 in Portugal using an adapted SIR Model previously used in South Korea for the MERS outbreak

Pedro Teles
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Abstract

The new coronavirus covid-19 has spread very quickly worldwide, leading the World Health Organization (WHO) to declare a state of pandemic. One of the questions many policy makers, and governments are asking themselves is how the spread is going to evolve in time. 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, using Italian dara. I then construct five different scenarios for the evolution of covid-19 in Portugal. In the out of control scenario, the number of active cases could reach as much as ~40,000 people on the 5th of April (out-of-control scenario). If the self-protective and control are taken in the same level as what was considered for the South Korean model, this number could have be reduced to about 800 cases (scenario 1). Considering that this scenario is now unrealistic, three other scenarios were devised. In all these scenarios, the government measures had a 50\% effectiveness when compared to the measures in Korea. But in scenario 2 the transmission rate $\beta$ was effectively reduced to 50\%, In this scenario active cases could reach circa 7,000 people. In scenario 3, the transmission rate $\beta$ was reduced to 70\% of its initial value, in which the number of cases would reach a peak of ~11,000 people. And finally in scenario 4, $\beta$ was reduced to 80\%. In this scenario, the peak would be reached at about ~13,000 cases. This study 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 ~7,000-13,000 people. Hopefully that will be the case not just in Portugal, but in the rest of the World.

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Pedro Teles. 2020-03-23. Predicting the evolution Of SARS-Covid-2 in Portugal using an adapted SIR Model previously used in South Korea for the MERS outbreak. https://arxiv.org/abs/2003.10047

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