Text/Wu Zunyou Editor/Shi Dong
Editor's Note
Entering 2022, the new crown epidemic seems to become more severe, and the United States has more than one million new confirmed cases of new crown in one day, creating a new global single-day new record. Compared with the four epidemic peaks that have appeared in the past world, Wu Zunyou, chief epidemiologist of the Chinese Center for Disease Control and Prevention, said that after the spring of 2020, there have been basically no major epidemic infections in China, thanks to the adherence to normalization of epidemic prevention.
On December 29, 2021, at the "Please Answer 2022 · 2021 Tencent Fengyun Speech Annual Conference", Wu Zunyou delivered a speech entitled "Adhere to Normalization and Epidemic Prevention to Help Healthy People's Livelihood", he said that in fact, the mutation of the virus occurs every day. However, whether it is the Delta strain, or the introduction of Themi kerong, China's public health measures, the whole process of vaccination, including the vaccination of the reinforced needle, can effectively prevent the emergence of the Delta strain, the Omiljung or other new mutant strains. No matter how the virus mutates, the normalized prevention and control strategy is effective.
The following is the main text. (Atomic Think Tank is based on on-site records)
I am Wu Zunyou, from the Chinese Center for Disease Control and Prevention, who has been engaged in the prevention and treatment of infectious diseases for more than 30 years. The title of my speech today is "Adhere to Normalization of Epidemic Prevention and Help Healthy People's Livelihood". I would like to talk about three main aspects:
First, what exactly does normalization of epidemic prevention include?
Second, the current global epidemic situation.
Third, how do we confront the COVID-19 mutant strain.
In the past year and nearly two years, the new crown epidemic has set off terrifying waves around the world, and normalized prevention and control is a way for China to maintain stability, and with normalized prevention and control, it has ensured the stability and development of China's economy and society.
What is the content of normalization prevention and control? I combed through it and there were 11 in total.
First, personal protective measures such as social distancing, wearing masks, and hand hygiene;
Second, if you have symptoms such as fever, you must go to the fever clinic in time;
Third, when there are symptoms such as fever, we can no longer participate in parties, travel, and other behaviors that may cause transmission until the diagnosis is confirmed;
Fourth, everyone should be vaccinated in a timely manner and, if necessary, given a booster injection.
These four points should be done by each of us.
There are also seven articles mainly carried out by the relevant government departments, which require the cooperation of ordinary people.
Fifth, isolate people entering the country and deal with new coronavirus cases in a timely manner.
Sixth, regular testing of high-risk groups engaged in cold chain, outer wheel handling, etc., so that new crown infection cases can be found in a timely manner and disposed of.
Seventh, after the local outbreak, the epidemiological investigation should be started in time, the transmission chain should be sorted out, and the transmission should be cut off.
Eighth, after the discovery of the local epidemic, the whole population screening was carried out in the local area to detect the early infected people in a timely manner.
Ninth, all clearly diagnosed infected people and cases should be isolated and treated in a timely manner.
Tenth, all close contacts and sub-close contacts should be isolated for observation.
Last, when necessary, the local community is sealed and controlled.
These eleven articles are the main content of normalized prevention and control.
What does normalized prevention and control bring us? On the left is the situation of the epidemic in China. After the spring of 2020, there have been basically no major outbreaks in China, although there have been more than 40 outbreaks, and each outbreak has not exceeded 2,000 cases from a few, dozens, and hundreds. Looking at the right side of the picture, there have been four peaks of fashion in the world's new crown epidemic, and it is now in the fourth peak of popularity.
Through comparison, it can be found that if the incidence and death of China are similar to the global average, and the normalization of prevention and control is adopted, more than 47.8 million infections and about 950,000 deaths are prevented. If the incidence and death in China are similar to the average in the other four BRICS countries, then we have prevented about 54.97 million infections and about 1.14 million deaths. If the level of morbidity and death in China is similar to that of the developed United States and the United Kingdom, then our normalized prevention and control has prevented about 204 million to 206 million infection cases, and prevented about 3.05 million to 3.15 million deaths.
If the conservative estimate of the normalization of prevention and control strategies has led to at least 50 million fewer infections and 1 million deaths in China, this is the most conservative estimate. Therefore, normalized prevention and control has ensured the stable development of China's social economy in the past year, guaranteed The Chinese family, and ensured the safety of the people's lives.
In the second aspect, let's talk about the situation of the epidemic.
The global epidemic situation is unevenly distributed, with key countries accounting for 60% of the world, and the number of cases in the top ten accounts for more than 60.3% of the world, of which the United States alone accounts for 18%. Recently, that is to say, at the fourth peak of the epidemic, by December 10, 2021, 86% of the new cases were in Europe and the United States, and 10 countries with serious epidemics were mainly concentrated in Europe and the United States, accounting for nearly 60%.
Looking at the distribution of the epidemic on six continents around the world, the first is the Americas, the Americas is still the outbreak of the new crown, but Europe has become the epicenter of the current fourth wave of the new crown epidemic peak, we can look at the picture of Europe on the right, the fourth wave peak, has exceeded the first three peaks.
Looking at Asia and the Middle East, these two regions are not too influential in the fourth wave of global epidemic peaks.
In the Western Pacific and Africa, the Western Pacific remains at an average level, but a fourth peak of epidemic is also occurring in Africa, which has already caught up with the previous peaks. In Africa in particular, there has been a heated media discussion about the new mutant strain of Aomi Kerong.
Let's take a look at the outbreak in South Africa. South Africa has also seen four epidemic peaks, and the fourth epidemic peak is now happening, and this peak has caught up with the second and third peaks in front of it, mainly because Ofickron has pushed the epidemic further up.
In addition to these countries and regions, there are several countries where the epidemic deserves in-depth study. There are two countries in Asia that deserve special attention, one in India and the other in Japan. Both countries had very severe outbreaks a few months ago and are among the most serious countries in the world. In the past two months, the epidemic has suddenly been under control, what measures have they taken to control the epidemic? It is worth further studying.
In Europe, I also picked two countries, one is Germany and the other is the United Kingdom. Germany is a country with relatively good epidemic control in Europe, but in the autumn and winter of 2021, at the peak of the fourth wave of the epidemic, Germany became the most serious country in the world and became the center of this epidemic storm, with more than 60,000 to 70,000 daily reports, and the country's two-shot vaccination rate reached 70%. The UK is a country that has led the world in public health for nearly two hundred years, but the covid-19 epidemic in this country has remained high, and in recent months the number of daily reports has been basically 30,000, 40,000, or even 50,000, which is rare in European countries. Why is it that a country with such a developed public health has such poor epidemic control and a two-shot vaccination rate of nearly 75%.
Look at the Americas. In the world, whether it is economy, science and technology, the United States is the strongest country, but in this epidemic, the United States has become the worst country to deal with the new crown, the United States infected cases, causing deaths are the most serious countries in the world. Brazil in South America has been closely following the United States, and the epidemic is running at a high level, but since the second half of this year, we have seen that the epidemic in Brazil has gradually declined and stabilized at a very low level, so what measures Brazil has taken is also worthy of our further study and analysis.
In the third aspect, I will talk about how to meet the new crown mutation.
Delta strains remain the dominant global epidemic strains, whether in the United States, the United Kingdom, India, including South Africa. The red color in the figure above shows the distribution of delta strains throughout the entire epidemic strain. Although Omikejong has been reported and spread to more than a hundred countries around the world, most countries have only a few dozen, hundreds, thousands of cases. South Africa, the United States, the United Kingdom and other countries may be more, and the number of cases of Amickron infection in other countries is not very high. So we're still going to talk about how to deal with Delta.
This is the case of China's Kexing vaccine to prevent Delta infection and prevent severe death, and this article was published in the top medical journal "New England Journal of Medicine", reflecting the real-world research in Chile. Our inactivated vaccines are 65% protective of COVID-19, 87.5% against hospitalization, 90% against admission to the ICU, and 86.3% against death. It is very, very difficult to achieve such good results in the real world, which shows that our inactivated vaccine is very effective in fighting COVID-19.
China's other vaccine Zhifei protein vaccine, the total effective rate of Delta's mutant strain can reach 81%, but also has a very good effect.
Coxing Vaccine Company made a reinforcing needle for the inactivated vaccine, and after the third booster needle, it was found that the titer of the antibody rose quickly and was maintained at a high level. Whether it is 18-59 years old, or older than 60 years old, people have shown that the booster needle has improved the titer of antibodies and improved the preventive effect of the vaccine, and this result was just published in the Lancet's Journal of Infectious Diseases in December, which is also a very authoritative journal. This result shows that strengthening the target is very effective in preventing mutant strains or Delta.
Let's take a look at the research on the preventive effect of inactivated vaccines against Delta variant strains in China by Academician Zhong Nanshan's team. If a person only gives a single dose of inactivated vaccine, then its protective effect is only 13.8%, if two doses of inactivated vaccination is completed, that is, the whole process of vaccination is completed, the protection rate rises to 59%, its effect of preventing ordinary pneumonia reaches 70%, and the effect of preventing severe disease reaches 100%. This study is the result of an imported outbreak of Delta that occurred in Guangdong in June and July, and it is also a real-world study, which further strengthens our confidence that inactivated vaccines are effective for Delta variants.
When it comes to mutant strains, it is impossible to avoid Aomi Kerong. Because of the media reports, the reflections of various countries, and the attention of the people, the topic of Omicron has made everyone very concerned. According to the prediction and analysis of the data model, it is believed that Omilon is a mutant strain that is more infectious than Delta, because this strain has 32 mutation sites in the spike protein of the virus, making it more closely bound to our human body, so it is speculated that it is more contagious.
In fact, the mutation of the virus occurs every day, the picture above shows the mutation of the virus since the new crown epidemic, from Alpha to Beta, Gamma, Delta, Delta is the dark green color on the image, and it is also the main epidemic strain in the world. The red color is Omi kerong, and it can be seen that the virus structure of Omi kerong is very different from the mutation of several other strains, and it is immediately separated from several other strains.
Everyone is concerned about the Omikejong mutation, the most important of which is three core questions: is the first contagious enhancement? Does the second pathogenicity enhance? Third, does our vaccine still work?
First look at whether its infectivity has increased or not. So far, all reports have suggested that Omilon is more contagious than Delta, but we don't yet have a definitive scientific basis to prove it, what is the most important epidemiological indicator to measure contagion? It is called the transmission coefficient, or regeneration index, that is, how many people can be infected by each patient on average, and how many people can be infected.
According to the latest South African study, the spread coefficient of Omi kerong is 2.55, what does it mean? On average, each infected person in Aomi Kerong, they infect 2.55 healthy people. Looking at the transmission coefficients of other strains, before Delta we called the previous strains, in the global study, the previous strains in Spain were 2.9, found in Italy is 2.83, Ecuador is 3.95, Panama, Brazil is also 3.95, peru 2.36, we analyze all the new crown in the world, its average transmission coefficient is 2.97, this transmission coefficient is higher than the 2.55 reported by South Africa.35.
Looking at Delta's propagation coefficient, Delta's propagation coefficient is 5.08. Through the analysis of these scientific data, it is not yet possible to conclude that the infectivity of Omi kerong is enhanced. The spread of the strain needs to be further observed.
The second aspect, is it more pathogenic? Limited data from South Africa suggest that the clinical symptoms of patients infected with the Omiljung strain are no more severe than those of other strains, or that the clinical symptoms have become milder and milder, that is, the pathogenicity has not increased.
Third, will it cause the vaccine to be ineffective? South African researchers analyzed that after analyzing the cases of 35,670 repeat infected people, it was found that the protection that the previous infection could provide was only half of the protection of the Delta strain for Themi kerong, that is to say, the protection effect of the previous infected person for the Olmi kerong was not as good as the protection effect on the Delta.
To some extent, Omi kerong will lead to a decrease in the effectiveness of vaccines, how much it will fall, and what the impact on which vaccine will be unclear. But one thing is clear, because the mutation of Omikejong mainly occurs in the site of the spike protein, the impact on the vaccine with the spike protein as the strategy is certainly large, and the impact on the inactivated vaccine will not be too large.
Our prevention and control strategy must still adhere to the normalization of prevention and control, the current global epidemic is still Delta virus, whether Omi kerong can become the global epidemic strain needs to be further observed, whether it can spread around the world like Delta now, instead of Delta, it is still an unknown.
Whether it is the Delta strain, even if it is the introduction of Themi kerong, China's public health measures, the whole process of vaccination, including the vaccination of the reinforcing needle, can effectively prevent the emergence of the Delta strain, the Omiljung or other new mutant strains. No matter how the virus mutates, our normalized prevention and control strategy is effective, as long as we adhere to the normalized prevention and control strategy without wavering, we will certainly be able to win the epidemic defense war of "external prevention of import, internal prevention and rebound".
Produced by Atomic Think Tank Tencent Xiaoman Studio | Issue 517
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