Research On Transmission Dynamics Model Based On AIDS And Novel Coronavirus Pneumonia Epidemic Prevention And Control

Section 1 Research on theoretical model based on the epidemic trend of AIDS and antiviral therapyObjectives:To develop a suitable transmission dynamic model for chronic infectious diseases-acquired immunodeficiency syndrome（AIDS）to fit and forecast the trend of AIDS epidemics.Methods:Considering the disease progression,antiviral therapy（ART）and drug resistance of AIDS among men who have sex with men（MSM）,we developed a SPIA transmission dynamic model to evaluate the effect of antiretroviral therapy,contact rate and diagnostic rate on the epidemic.At the same time,we constructed an ART prognosis model,and predicted the death risk among the people who live with HIV（PLHIV）through the multi-indicator comprehensive nomogram,and use bootstrap sampling for internal verification.Results:The SPIA model results show that under the present condition,the AIDS epidemic of MSM population in Zhejiang province will not tend to disappear in theory,with the R₀ of 2.39（95%CI:2.29,2.49）.We predict that by 2020,90%of HIV/AIDS will have access to treatment,but the proportion of diagnosis is still as low as 40%,far from the target of 90%.A 50%reduction in effective contact equates to a six-fold increase in diagnostic rate.Conclusions:Carry out ART to control the AIDS epidemic has a remarkable effect.Behavioral and biologic interventions are the most effective interventions to control the AIDS epidemic among MSM.Prognostic models can predict the risk of death of PLHIV in a timely and accurate manner and are essential for effective management of antiviral therapy by clinicians and healthcare providers.Section 2 Analysis of COVID-19 epidemic trends based on transmission dynamics modelObjective: To study the trend of COVID-19 epidemic situation and SARS-Co V-2 infectious power under the condition of no prevention and control measures in closed space,to evaluate the effect of closure and centralized isolation on epidemic prevention and control in Wuhan,and to analyze the epidemic situation trend and forecast the epidemic scale.Methods: The data were collected from the daily cumulative confirmed case data published on the official website of the National Health Council of China and the open data set of Johns Hopkins University.Using the early fever data of the "diamond princess" cruise ship to fit the classical SEIR model;to study the epidemic situation of Wuhan COVID-19 retrospectively,to consider the measures of asymptomatic infection and confirmed isolation,to construct the SEIAHR model,to fit the number of confirmed cases accumulated daily in Wuhan in three stages;to apply the constructed SEIAHR model to overseas countries and regions,to calculate their basic regeneration number,and to predict the peak value,time and scale of epidemic situation in various countries under the current state of prevention and control.Results: The basic reproductive number of COVID-19 among passengers and crew members in the "diamond princess" cruise ship without intervention is R0=3.49（95%CI:2.3830,3.7301）.Without prevention and control measures,the peak was 967（95% CI:476,1773）on 28 February,and the outbreak ended on 28 April,bringing the cumulative number of infections to 3599（95%CI: 3207,3721）,with almost all infected.Wuhan city before the shutdown of R0=3.6841（95% CI:3.1061,4.0480）;from the shutdown to the centralized isolation stage R0=2.1788（95% CI: 1.7258,3.5776）;after centralized isolation,the R0 fell to 0.3625（95%CI: 0.3499,0.3676）,less than the threshold 1,and the epidemic tended to end.Wuhan shutdown and centralized isolation measures may have prevented about 1.03 million people from being infected with SARS-Co V-2;the centralized isolation measure may have reduced about 480,000 infectious people.Russia,the Philippines,Finland and Kyrgyzstan R0 are all greater than 4;Britain,the Netherlands,Ireland,Austria,Pakistan,Belarus and other 12 countries R0 more than 3;New Zealand,Vietnam,Luxembourg,Cambodia,Brunei,Madagascar and other 19 countries R0 less than 1.Conclusions: The infectious power of SARS-Co V-2 is very strong,and the measures of Wuhan shutdown and centralized isolation are very important for the prevention and control of COVID-19 epidemic situation.At present,the COVID-19 pandemic in some countries abroad has leveled off,but most of them are still at the mid-term level of Wuhan COVID-19 epidemic.