Question B of the East China Cup: how to establish a population immune barrier against novel coronavirus?

subject ：

B topic Establishment of COVID-19 colony immune barrier In order to consolidate the foundation of economic growth 、 Guarantee domestic and international double circulation , The Chinese government has decided to carry out Novel coronavirus vaccination for the whole population , In order to build a new immune barrier for the largest national population . 1. Establishment of mathematical model of population immune barrier of infectious virus , It shows that the control of vaccination rate is of great importance to the construction of The role of the immune barrier . On this basis, the effectiveness of the vaccine and the variation of the virus are considered The possible effects of obstacles . The cost and benefit of immune barrier and physical isolation for the whole society are discussed . 2. Take a big city in China as an example , Consider what steps to take 、 How much does it cost 、 How long It can complete the establishment of group immune barrier . 3. The United States is the most serious country in the world COVID-19. , It's also massive 、 Get the new crown vaccine quickly One of the countries of , Recently, the epidemic situation in the United States has shown signs of improvement , Try to analyze the impact of vaccination on the change of epidemic situation in the United States , Forecasting the trend of the epidemic in the United States .

 

Follow up group update ideas , The question is simple , The model is fixed - Differential equation models （SIR Infectious disease model ）,

The emphasis is on the improvement of the vaccination rate on the infectious disease model （ Easy or hard ） . The difficulty lies in the cost 、 Quantification of the impact of changes in the US epidemic .

（ This time   Ideas   The focus of this paper is to simplify and explain the code of infectious disease model ）