On February 12, Zeng Guang, chief epidemiologist of China Center for Disease Control and prevention, posted an article on his personal micro blog, saying that the inflection point of the decline of the epidemic situation has appeared, but there is still a potential inflection point of the rise.
The following is an excerpt from Zeng Guang’s microblog:
New thinking on the current situation: the inflection point of the decline of the epidemic situation has appeared, but there is also a potential inflection point of the rise.
1. In epidemic analysis, turning point refers to the turning point of epidemic trend of infectious diseases, which is a concept of time point. For epidemiologists, we often see the inflection point of the decline and the rise of the epidemic situation of various infectious diseases in the whole country or a certain province, as well as the alternation of the inflection point of the rise and fall. Therefore, don’t complicate the concept of inflection point, and don’t simply understand the overall situation of inflection point.
2, according to the different prevention and control situation of New Coronavirus pneumonia in mainland China, it can be divided into the battlefield of Wuhan / Hubei province and the battlefields of provinces, municipalities directly under the central government and autonomous regions outside Hubei.
Among them, the number of daily confirmed cases in provinces, municipalities and autonomous regions outside Hubei Province has dropped for six consecutive days, with the inflection point of the decline around February 5. It should be pointed out that this is the inflection point calculated according to the number of confirmed cases. As each patient has to go through the whole process of exposure infection incubation onset treatment diagnosis before diagnosis, the actual inflection point should appear much earlier than the diagnosis time.
For 17 years, I was responsible for the monitoring and statistical analysis of the epidemic situation of infectious diseases in China. Through the analysis of the epidemic situation of coronavirus pneumonia, I predicted in advance that the inflection point of the number of confirmed cases in provinces, municipalities and autonomous regions outside Hubei Province would appear 5-10 days after the “closure of Wuhan”. I also proposed that the 15th day of the first lunar month would come to an end.
As far as I know, the epidemic analysis experts of the National Center for Disease Control and prevention have been taking the time of diagnosis and the time of onset as the inflection points for statistical analysis. According to the time of onset, the inflection point for the decline of the epidemic situation has appeared within three days after the “closure of Wuhan City” on January 23. With the progress of time, this inflection point has become more and more clear.
It is not difficult to understand that due to different majors, some scholars have different understanding of the inflection point. I don’t mind the unprofessional comments of the media and netizens on the inflection point.
What is important is that we are all concerned about the trend of the epidemic and actively participate in it. It is necessary to recognize the declining inflection point after the concept is unified, so as to gain more confidence for China’s arduous and great prevention and control work.
3. I have to predict that after the inflection point drops, it is difficult to avoid another inflection point when the epidemic situation rises. The reason is that we must not underestimate the negative impact of the return flow of as many as 160 million people on the epidemic, and the impact on the Pearl River Delta, Yangtze River Delta and Beijing Tianjin Hebei region is the first to bear the brunt.
The mobile army, whether by train, long-distance bus or by plane, is in a closed environment, which is easy to cause the spread of the virus. After returning to the city, it needs to do a lot of hard work to pass the longest incubation period safely.
I predict that the inflection point will appear one latency later than the return peak according to the time of onset. If it is estimated according to the time of diagnosis, it will be delayed about one week later. Is the turning point of local rise really emerging? And the magnitude of the rise? It directly tests whether the prevention and control work in various places is solid.
What worries me most is that as the epidemic statistics are delayed in the time of infection, what we have seen in recent days is still the continuous decline of the epidemic situation, which covers up the actual upward trend caused by the return infection and makes people relax their vigilance.
Come on! After that, we can see more objectively how far away we are from the decisive victory of the epidemic prevention war.