Two-Stage SEIRH Model Verification Based On COVID-19 Epidemic Data

Infectious diseases have always been a major threat to mankind.According to authoritative data from the World Health Organization(WTO),infectious diseases have become the chief culprit leading to human deaths.In history,there have been many outbreaks of infectious diseases,threatening human life and health and social stability,and causing huge loss of life and property.In 2020,the outbreak of coronavirus(COVID-19)caused a huge disaster.Due to the particularity of infectious diseases,compared with experiments,the research on infectious diseases is mainly based on theoretical analysis and mathematical model simulation.The epidemic compartment model is a model which mainly studies the transmission speed,space range,transmission route and dynamic mechanism of infectious diseases in order to effectively prevent the spread of infectious diseases.In these models,the population is divided into multiple Category.And the logical relationship between each category is studied.Due to COVID-19 epidemic in 2020 has several stages,and the patients in incubation stage are also spread the disease compared to ordinary infectious diseases.Based on the deficiencies of the existing literature,the article divides the epidemic situation into a two-stage analysis.A SEIRH(Susceptible-Exposed-Infectious-Recovered-Hospitalized)model is established and the model is expected to provide a better result and reflect the development trend of COVID-19.This article first starts from the research on infectious disease modeling,analyzes and compares domestic and foreign research on infectious disease model and COVID-19 related research content including model building methods and parameter fitting methods.Subsequently,two types of epidemic models are introduced according to the incubation period including the SI model,SIR model,SEIR model and other classic infectious disease warehouse models,the basic theory of the infectious disease warehouse model and the key parameters of the model and the calculation method of the key parameters of the model and its basic reproduction number were introduced.After that we introduced the theory and existing research on exponential smoothing,which is used to forecast the pandemic in the first stage.Then the article establishes the SIR,SEIR infectious disease model and establishes the SEIRH model considering the lurking person and isolation factors on the basis of the SEIR model and divides the target population into 7 categories including susceptible group,infected group,exposed group,isolated susceptible group,isolated exposed group,hospitalized patients and recovered group,this model considers the infectiousness of the exposed group and adding the epidemic transmission control coefficient according to the intensity of the government’s epidemic prevention measures,which is more in line with the spread of COVID-19 epidemic.Later,by collecting data on the new crown epidemic in Hubei province from January to April 2020,a two-stage empirical analysis of the spread of the COVID-19 epidemic was carried out.A combined forecasting method,including exponential smoothing were used in the free spread stage when population movement control was not implemented in the early stage of the disease.The methods are used to fit the cumulative number of confirmed cases,cumulative number of death cases.The SIR model,SEIR model and improved SEIHR infectious disease warehouse are used in the control phase of the city closure and first-level response measures.The model is fitted.The development of the epidemic was predicted,and the fitting effects of the three models on the epidemic were compared with.Then the article calculated the basic reproduction number of this COVID-19 epidemic and compared it with several other types of infectious diseases,and found that this epidemic is completely controllable.Then this paper conduct a simulation on the disease: through advancing and delaying the date of taking prevention and control measures for several days in the first stage,and the changing the epidemic spread control coefficient in the second stage,the calculation of the final number of people infected during the epidemic through simulation shows that the prevention and control measures should be taken as early as possible and as widely as possible before the outbreak of the disease.Also,improving daily protection measures and health status of resident also has positive effect on defending the epidemic.Based on the result,this paper provide several recommendations on epidemic prevention and control based on the findings and has a certain reference effect.