Estimating the number of COVID-19-related infections, deaths and hospitalizations in Iran under different physical distancing and isolation scenarios: A compartmental mathematical modeling
Authors: Sharifi Hamid , Jahani Yunes , Mirzazadeh Ali , Gohari Milad Ahmadi , Nakhaeizadeh Mehran , Shokoohi Mostafa , Eybpoosh Sana , Tohidinik Hamid Reza , Mostafavi Ehsan , Khalili Davood , Hashemi Nazari Seyed Saeed , Karamouzian Mohammad , Haghdoost Ali Akbar 
Published: April 2020

AbstractBackgroundIran is one of the countries that has been overwhelmed with COVID-19. We aimed to estimate the total number of COVID-19 related infections, deaths, and hospitalizations in Iran under different physical distancing and isolation scenarios.MethodsWe developed a Susceptible-Exposed-Infected-Removed (SEIR) model, parameterized to the COVID-19 pandemic in Iran. We used the model to quantify the magnitude of the outbreak in Iran and assess the effectiveness of isolation and physical distancing under five different scenarios (A: 0% isolation, through E: 40% isolation of all infected cases). We used Monte-Carlo simulation to calculate the 95% uncertainty intervals (UI).FindingsUnder scenario A, we estimated 5,196,000 (UI 1,753,000 - 10,220,000) infections to happen till mid-June with 966,000 (UI 467,800 - 1,702,000) hospitalizations and 111,000 (UI 53,400 - 200,000) deaths. Successful implantation of scenario E would reduce the number of infections by 90% (i.e. 550,000) and change the epidemic peak from 66,000 on June 9th to 9,400 on March 1st. Scenario E also reduces the hospitalizations by 92% (i.e. 74,500), and deaths by 93% (i.e. 7,800).InterpretationWith no approved vaccination or therapy, we found physical distancing and isolation that includes public awareness and case-finding/isolation of 40% of infected people can reduce the burden of COVID-19 in Iran by 90% by mid-June.FundingWe received no funding for this work.Research in contextEvidence before this studyIran has been heavily impacted by the COVID-19 outbreak, and the virus has now spread to all of its provinces. Iran has been implementing different levels of partial physical distancing and isolation policies in the past few months. We searched PubMed and preprint archives for articles published up to April 15, 2020 that included information about control measures against COVID-19 in Iran using the following terms: (“coronavirus” OR “2019-nCoV” OR “COVID-19”) AND “Iran” AND (“intervention” OR “prevention” OR “physical distancing” OR “social distancing”). We found no studies that had quantified the impact of policies in Iran.Added value of this studyGiven the scarcity of evidence on the magnitude of the outbreak and the burden of COVID-19 in Iran, we used multiple sources of data to estimate the number of COVID-19 infections, hospitalizations, and deaths under different physical distancing and isolation scenarios until mid-June. We showed that implementing no control measures could lead to over five million infections in Iran; ∼19% of whom would be hospitalized, and ∼2% would die. However, under our most optimistic scenario, these estimates could be reduced by ∼90%.Implications of all the available evidenceWith no effective vaccination or treatment, advocating and enforcing physical distancing and isolation along with public education on prevention measures could significantly reduce the burden of COVID-19 in Iran. Nonetheless, even under the most optimistic scenario, the burden of COVID-19 would be substantial and well beyond the current capacity of the healthcare system in Iran.