Can judgments according to case fatality rate be correct all the time during epidemics? Estimated cases based on CFR in different scenarios and some lessons from early case fatality rate of coronavirus disease 2019 in Iran

Background: The new Coronavirus disease (COVID-19) was first identified in China in2019. Case fatality rate (CFR) indicator of the disease is one of the most important indicesnoticed by experts, policymakers, and managers, based on which daily evaluations andmany judgments are made. CFR can change during epidemics. This study aimed toestimate the actual number of COVID-19 cases in Iran and to calculate the early CFR forthe disease based on official statistics)Material and Methods: This was a descriptive study whose data were obtained from thewebsite of the Ministry of Health and Medical Education of Iran from February 20, 2020until March 26, 2020. CFR has been obtained by dividing the total number of deaths bythe total number of confirmed cases at one point in time. In this study, the actual numberof COVID-19 cases in Iran was estimated based on the mortality model in 4 scenarios.Excel 2013 software was used to analyze the dataResults: According to the findings of this study, In Iran, until March 26, 2020, a total of 27017 people have been infected by COVID-19 and 2077 died of it. However, CFR indicatorhad a descending trend in Iran: 100%, 18.6%, 8.8%, 3.3%, 6.9%, and 7.7% on days 1, 5, 10,20, 30, and 35, respectively. The actual number of COVID-19 cases in Iran was estimated tobe 4 789 454, 2 873 673, 1 436 836, and 718418 as of March 26, 2020 according to the 4scenarios, respectivelyConclusions: In emerging epidemics, CFR indicator must not be used as a basis to judge theperformance of a health system unlessthat epidemic condition has been clarified. Moreover, itis suggested that in the outbreak of an epidemic, specifically emerging diseases, CFR mustnot be the base of judgment. Making judgments, specifically in the outbreak of emergingepidemics, based on fatality rate can lead to information bias. It is also possible to estimatethe total number of patients based on the CFR in circumstanceswhere little information isavailable on the disease.

کلیدواژه ها:

Coronavirus ، COVID-19 ، Case fatality rates ، Pandemic ، Mortality estimated model ، Iran