This issue of popular science comics mainly introduces the concept of the basic reproduction number R0 and the mathematical principles of herd immunity. The basic reproduction number indicates how many people an infected person will infect on average without control. The larger the basic reproduction number, the stronger the virus's ability to spread. Assuming the basic reproduction number of the new coronavirus is 3 and the infection cycle is 4 days, it will only take more than 80 days to infect everyone in the world without control. The way to eliminate the virus is to use vaccines: vaccines can make people immune, which can protect themselves and cut off the virus's transmission chain, thereby protecting others. It is because of vaccines that humans have defeated smallpox, rabies, polio... Now, the new coronavirus vaccine is on the market. Friends who are in good physical condition, please be brave and get vaccinated! Produced by: Mr. Li Yongle |
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