Enlightenment of China's normalization of epidemic prevention

　　"China News Weekly" reporter / Du Wei and Li Xiangmao

　　Published in the 969th issue of China News Weekly on October 26, 2020

　　Images and texts with the words "Qingdao Speed" spread all over the media release platform. Volunteers shouted "Little sisters and old sisters go downstairs for nucleic acid testing" with loudspeakers. There are also long queues and bodies in front of thousands of test points. Medical staff in protective clothing waiting in battle.

Due to the occurrence of 3 cases of asymptomatic infections of new crowns in Qingdao linked to Qingdao Chest Hospital, a massive national test, which was called a record-setting by Qingdao Deputy Mayor Luan Xin, was carried out in Qingdao.

　　On the day the source of infection of the epidemic was announced on October 16, the results of nucleic acid testing of more than 10 million people within 5 days were released. Except for the 13 confirmed cases that have been discovered, there were no new cases.

Large-scale nucleic acid testing, flow tracking, isolation treatment, and "dynamic zeroing"... have become a magic weapon for local outbreaks in the past six months after the country passed the darkest moment of the initial epidemic.

　　At present, the global epidemic situation is one after another. Relying on the adherence to the strategy of "prevention from outside, non-proliferation inside", China has become an "oasis" in the world's new crown pandemic.

However, with the huge investment of human, material and financial resources, is such a sticking strategy sustainable? How should China respond to the fall and winter or the coming second wave of the new crown epidemic?

"Dynamic Zeroing" under large-scale nucleic acid detection

　　This nucleic acid test in Qingdao was ridiculed by netizens as "the seventh census can be completed at the same time."

Starting overnight on the evening of October 11, the five districts of Qingdao City will be fully covered in 3 days, and the whole city will be covered in 5 days.

By 20 o'clock on the 15th, the city's sampling exceeded 10 million, with 9 million results, all of which were negative.

　　National testing is not the first of Qingdao.

In May of this year, after six new confirmed cases were added to a community in Wuhan for two consecutive days, Wuhan immediately launched the "ten-day battle" of nucleic acid testing for the city's nearly 10 million people.

In order to increase the detection speed, in addition to the conventional means of increasing the testing institutions, testing personnel and equipment, Wuhan has adopted a mixed testing technology of no more than 5 samples at a time for the first time.

The so-called mixed test is to test the throat swabs of different people together. If the result is positive, then the individual tests are performed separately. This practice also caused controversy at that time.

In the end, 300 asymptomatic infections were detected in the "Ten Days Battle" in Wuhan, with a detection rate of 0.303 per 10,000.

　　In the new outbreak in Beijing in June, Beijing also adopted a mixed inspection method. The number of testing institutions in the city has increased from 98 in early June to 128 as of June 22, and the maximum daily detection capacity has increased from 100,000 to 100,000. More than 450,000 copies.

As of July 2nd, a total of 10.059 million people had been tested, which accounted for nearly 50% of Beijing's permanent population at the end of 2019, but the positive rate was only 0.00367%.

　　In order to further improve the detection efficiency, after the outbreak of the Dalian epidemic on July 22, Liu Yong's team, director of the laboratory of Shengjing Hospital affiliated to China Medical University, developed a "new coronavirus nucleic acid 10-in-1 mixed detection technology."

Liu Yong told China News Weekly that because the mixed sampling test can control the dilution concentration, it can ensure the detection of weakly positive nucleic acid viruses.

With the support of this new technology, Dalian City completed nearly 4.5 million inspections in the main urban area within 6 days.

Since then, the outbreaks in Xinjiang, Ruili, Yunnan and this time Qingdao have also adopted 10-in-1 mixed sampling testing.

　　During the outbreak in Beijing, the New York Times commented that proactive testing and tracking of close contacts is the key to China's ability to contain the epidemic.

But in fact, China did not choose to do this at the beginning. After learning the lessons of the early prevention and control of the Wuhan epidemic, it changed its prevention strategy.

Regarding the Qingdao epidemic prevention, Lien Verwijk, a reporter for Belgian "Latest News" in China, also said that the biggest difference between China and the West in fighting the epidemic is that "as long as a confirmed case is detected, the Chinese government, health departments and ordinary people will Act now. They won’t wait until 200 or 300 new infections are added every day.”

　　Huang Yanzhong, an international public health expert and senior researcher of global health at the US Council on Foreign Relations, analyzed to China News Weekly that if the goal is to extinguish the epidemic in the shortest time and achieve zero infection, the practice of large-scale testing in many places in China is reasonable.

But from a cost-benefit point of view, taking Qingdao as an example, is it necessary for the very small number of confirmed cases to mobilize all the people and carry out a nationwide test?

　　Huang Yanzhong believes that the population of nucleic acid testing should be more targeted and flexible based on the risk assessment results.

After the first detection of a positive or suspected patient, compared to large-scale or even national nucleic acid testing, a more effective method is to track and isolate close contacts and other key populations.

According to the actual situation, small-scale random sampling and testing of people in different regions can also be conducted, and targeted tracking can be carried out after a specific population with a high infection rate is found.

　　Jiang Qingwu, former dean of the School of Public Health of Fudan University, said that the decision-making of nucleic acid testing should be based on the scientific norms and framework of epidemiological investigations.

For example, when the Qingdao case is highly related to the chest hospital, this should be the focus and the scope should be appropriately expanded to achieve precise control.

Local governments should listen more to the professional opinions of disease control departments, especially higher-level disease control departments, before making decisions.

　　Even with newer and faster detection methods, national nucleic acid testing still requires a lot of manpower, material resources, and financial resources.

A total of tens of thousands of foreign support and local medical personnel participated in Qingdao nucleic acid testing, and more than 20,000 volunteers participated in sampling in the urban area.

Bo Shirong is a deputy head nurse of the Joint Surgery Department of the Affiliated Hospital of Qingdao University. There are 30 people working side by side in the community where she worked for sampling. They worked 608 hours in two days. The longest one person worked 15 hours a day, and the average sample was more than 600.

Some medical staff worked until 11:30 in the evening, then got up at 3:30 the next morning and went to the community to collect swab materials at 5 o'clock to continue to work.

　　Like nucleic acid testing in several other places, Qingdao’s national testing is also free.

The Qingdao Municipal Government has not yet announced the total cost of this test. Previously, the cost of centralized nucleic acid testing in Wuhan was about 900 million yuan, which was borne by the government.

　　Another magic weapon for China's epidemic prevention is joint prevention and control.

In the Qingdao epidemic, it is not only local residents in Qingdao who need nucleic acid testing. Beijing, Tianjin and other places have successively issued notices. Qingdao must hold a nucleic acid negative certificate within 7 days when coming to Beijing (Tianjin).

　　Zhang Yue and her friend went to Huangdao District, Qingdao, the southernmost area opposite to Shibei District, on October 4th. They returned to Beijing on the 7th. During this time, they did not go to the middle-risk area where the chest hospital is located or any other medical institutions.

But after returning to Beijing, for peace of mind and responsibility to others, he took the initiative to do nucleic acid testing, and signed a letter of commitment at the request of the community, and his friend also received a notice from the company requesting his nucleic acid test and was required to stay at home for 7 days. .

Bai Liang, who had not been to Qingdao recently, was purely "injured." On October 7, because of the shortage of tickets, he should have boarded the train from Weifang Gaomi Station and bought a ticket from Qingdao, so he received a request from the community to do nucleic acid. He needs to be isolated at home before the test results come out.

Fatal hospitality shortcomings

　　At the press conference on epidemic prevention and control held in Qingdao on October 16, the source of the local epidemic was announced. The two infected persons in Qingdao Port shared the CT room with the patients in the general ward during the hospitalization of the epidemic. For protection and disinfection Irregularities lead to contamination of the CT room.

At a press conference on October 17, Zhao Guolei, deputy director of the Qingdao Municipal Health Commission, said that the lessons of the epidemic are very painful. The standardized use of diagnostic and treatment equipment, including CT, will be the top priority of the examination, emphasizing that confirmed patients must It can be used alone and disinfected once it is used.

　　This is not the first time that a hospital in Qingdao has experienced hospitalization during the new crown epidemic.

In March of this year, Qingdao citizen Zhang XX went to Qingdao Jiaozhou Central Hospital for lung inflammation. He was first admitted to the isolation ward of the fever clinic and then transferred to the respiratory ward.

During the fever isolation ward, because the hospital admitted a person with suspicious symptoms who was later diagnosed with new crown, Zhang and his accompanying wife became related cases of overseas imported cases.

Later, patients and nurses who were in the same respiratory ward as Zhang were also infected.

　　In February this year, there was also a cluster of 10 people infected by a patient with chronic lung disease in the Ninth People's Hospital of Qingdao due to close contact with patients and family members from Tianmen, Hubei in the same room.

In mid-February, Qingdao also confirmed 5 cases related to Qingdao Fifth People's Hospital.

Based on this calculation, this epidemic is the fourth nosocomial infection of the new crown publicly disclosed in Qingdao.

　　In an interview with the media, Wu Zunyou, chief expert of epidemiology at the Chinese Center for Disease Control and Prevention, pointed out that the management of imported cases from abroad is divided into two situations. The designated hospitals that specialize in treating new crown patients are completely closed-loop and the risk of hospitalization is small. , And medical institutions that receive new crown cases and other patients at the same time must strictly divide the wards and use large-scale equipment separately.

　　Since the beginning of the new crown epidemic in China, nosocomial infections have become an unpredictable "sacred spot" in the epidemic prevention and control battles everywhere.

At the end of January this year, a cluster of new coronary cases occurred in the intensive care unit of the Department of Cardiology, Fuxing Hospital, Capital Medical University Affiliated to Beijing, resulting in a total of 34 confirmed cases and two positive infections.

Around February 20 this year, a long-term geriatric patient in Peking University People's Hospital was diagnosed with new coronary pneumonia.

The elderly patient had renal insufficiency and was suffering from aspiration pneumonia. After returning to Beijing from Xinjiang in January, his daughter and son-in-law took turns to visit the hospital.

Since then, the two have a fever and were diagnosed with new crowns on February 17.

　　During the COVID-19 pandemic, the largest number of people in hospitals and the widest spread was the clustered epidemic in Harbin.

The outbreak centered on Chen, an 87-year-old hospitalized patient, and caused about 80 patients, escorts, family members and medical staff of the First Affiliated Hospital of Harbin Medical University and the Second Hospital of Harbin City to be infected, and dozens of people died. Inter-provincial transmission occurred in Inner Mongolia.

　　At the end of March, Chen was admitted to the Second Hospital of Harbin City due to a stroke after having a meal with Guo, a related case imported from abroad. During the hospitalization, Chen had fever symptoms, but the hospital did not conduct nucleic acid tests on him.

After that, he was sent to the First Affiliated Hospital of Harbin Medical University for treatment, but the doctor did not perform a nucleic acid test on him. Instead, he was admitted directly to the 8-person ward of a respiratory department.

Since then, the chain of virus infection has continued to extend, and the number of infections has continued to rise.

During Chen’s hospitalization, the hospital did not effectively implement the “one patient, one accompany, one certificate” system. There were as many as 3 accompanying persons. The disorderly movement of accompanying persons was also one of the reasons for the increase in hospital infections.

　　Jiang Qingwu believes that in the face of the new crown epidemic, many shortcomings in the prevention and control of discharge are exposed. For example, there are some places in the fever clinics that should be set up specifically, and the patients do not separate fever patients from ordinary patients when they see the doctor. The two are the same. Enter through the door, take blood tests in one place and take medicine in the same place.

　　In Huang Yanzhong's view, after the initial period when only COVID-19 patients were admitted and other departments closed, the challenge facing the hospital is to ensure normal medical services and prevent the spread of COVID-19.

The wearing of masks, testing, and daily disinfection in hospitals must be in place. This not only requires more manpower and material resources, but also poses greater challenges to the management of hospitals.

　　"China News Weekly" noted that among the 13 confirmed cases of the Qingdao epidemic, no medical staff were infected, but patients, family members and several escorts were recruited.

In fact, since the end of the Wuhan epidemic, escorts have accounted for a certain proportion of hospital-related incidents related to new coronary pneumonia.

Jiang Qingwu analyzed, "Accompanying staff is a characteristic of our country. These people generally have a lower education level and relatively weaker hygiene habits." However, they have longer contact with patients and have greater exposure opportunities.

Moreover, usually the hospital does not provide accommodation for them, and the accompanying staff have certain social activities.

To prevent nosocomial infections, it is necessary to have strict requirements on the attendants and medical staff, requiring them to do personal protection and wear masks.

How to coexist with viruses to prevent foreign imports?

　　Over the past six months, "prevention of foreign imports and non-proliferation of internal defenses" has become the main tone of the domestic fight against the epidemic.

The source of the Qingdao epidemic-two loading and unloading workers in Qingdao Port were infected after loading and unloading imported frozen seafood.

The source of the new outbreak in Beijing, the latest speculation is that the staff were exposed to contaminated imported aquatic products and the outer packaging, which caused human-to-human transmission.

The Dalian epidemic also preliminarily ruled out the possibility of the spread of domestic cases, suggesting that the epidemic may have started in seafood processing workshops.

　　In the latest version of the "New Coronavirus Pneumonia Prevention and Control Plan" (referred to as the "Prevention and Control Plan") released on September 15, the prevention and control requirements for cold chain food processing and trading sites have been added.

Jiang Qingwu believes that it is necessary to consider refusal to import cold chain foods that are clearly judged to come from severely affected areas, and the source of infection and the chain of transmission of relevant employees should be further investigated.

　　On the other hand, China is facing the pressure of imported cases from abroad.

To some extent, with the rising number of confirmed cases worldwide, China seems to be in a "depression".

Since the National Health Commission notified the imported cases in early March, as of October 19, the cumulative number of confirmed imported cases overseas has been 3142.

However, it is worth noting that there have been no deaths in imported cases for more than six months.

In the local epidemics in Beijing, Dalian, and Xinjiang, zero deaths were also achieved, and most of the infected people were ordinary and mild.

　　According to Zhang Hongtao, an associate professor at the University of Pennsylvania School of Medicine, one possibility is that the toxicity of the new coronavirus is weakening, but at the same time, more importantly, public health measures such as wearing masks and maintaining social distancing are playing a role.

As the new crown virus will not disappear in a short period of time and the current imported cases have zero deaths, China should explore anti-epidemic strategies that have the lowest impact on social and economic activities.

Huang Yanzhong said that the high epidemic prevention wall built by the previous strict defense has caused many inconveniences for overseas people to return to the country, and it has also affected the tourism industry and foreign trade. Nowadays, without affecting prevention and control and increasing imported risks, it can be Flexible adjustments to existing epidemic prevention policies.

　　In the latest version of the "Prevention and Control Plan", it is mentioned that for persons who are not in the “four categories” entering the country, they can change from the original 14-day centralized isolation to the 7-day centralized isolation at the place of entry and then isolation at home if they have the conditions of closed transshipment and home isolation. In the 7-day mode, nucleic acid testing will be performed before the end of 7 days of entry and centralized isolation, and one nucleic acid test will be performed at their own expense after 14 days of quarantine.

Wu Zunyou said that this is based on the understanding of the law of detoxification after infection with the new crown. One to two days before the onset of symptoms and five days after the onset of symptoms are the peak periods of detoxification. The adjustment of the plan will not only bring convenience to the people, but also will not bring about prevention and control measures. Bring any impact.

　　Zhang Hongtao believes that the number of days of centralized isolation may be further optimized under the premise that nucleic acid testing of imported cases from local and overseas needs to be adhered to.

"It can be piloted in some cities first." This is a dynamic adjustment process. If an expanding trend of infection is found, the policy can be tightened. For the sake of insurance, while reducing centralized quarantine, home isolation time can be increased.

"Actually, we need to tighten externally and internally. When a case is detected, close contacts must be tracked and screened in time."

In addition, for high-risk susceptible groups such as the elderly and patients with chronic diseases, who face the risk of severe symptoms after infection, it is still necessary to take preventive measures such as wearing masks and reducing visits to crowded areas.

　　Huang Yanzhong believes that if these measures are in place, the imported risk will not increase. For the second wave of epidemics that may occur in autumn and winter, there is no need to "tighten the pockets and tighten the preventive measures."

In his view, the new coronavirus will eventually become an existence like the well-known flu, and it is more important for human beings to learn to coexist with the virus.

　　The new crown may not be just the biggest challenge China will face this autumn and winter.

"The biggest challenge we face this winter is how to distinguish the new coronavirus infection from influenza, adenovirus and other diseases." In September this year, Gao Fu, director of the Chinese Center for Disease Control and Prevention and academician of the Chinese Academy of Sciences, accepted Said in a media interview.

　　Huang Yanzhong believes that the flu vaccine may prevent co-infection and develop into a severe illness, and it can also be used as a basis for doctors to determine whether a patient is infected with the new crown.

But in the past, in China, the people's willingness to get a flu vaccine was not high, and this year's 50 million doses are facing a dilemma in short supply.

　　The new crown vaccine is also the focus of public anticipation.

According to Wu Guizhen, chief expert on biosafety in China's CDC, four domestically-made new crown vaccines produced by Sinopharm, Sinopharm, Kexing Zhongwei and Kangsino have entered Phase III trials, and some have entered the end of Phase III.

The two inactivated vaccines from Sinopharm Zhongsheng Company are expected to be put on the market by the end of this year.

However, from the laboratory to the vaccination site, a strict approval process is required.

Some special populations such as medical workers, disease control personnel, border inspection personnel, etc. have been vaccinated urgently.

　　On October 15th, Zhejiang Jiaxing Disease Control announced the "New Crown Vaccination Instructions" on the official WeChat account, clarifying that the injection range is susceptible people aged 18 to 59, and marking the price of 200 yuan per bottle (bottle), which requires injection A total of 400 yuan for 2 doses.

　　But Jiang Qingwu believes that what is urgently to be announced should be the indicators of vaccine safety and effectiveness, "how much is the probability of protection and how long the antibody can last? There is no beautiful scientific report published."

Zhang Wenhong, director of the Department of Infectious Diseases at Huashan Hospital Affiliated to Fudan University, also said that the new crown vaccine will first be vaccinated in key domestic populations. It is expected that the domestic public will not be able to receive a safe new crown vaccine until the first half of next year.

The mass production of vaccines is also an issue that needs to be considered.

Jiang Qingwu said that this means that the prevention and control of the epidemic in this autumn and winter season still mainly depends on the implementation of public health policies.

　　(Zhang Yue and Bai Liang are aliases in the text)

　　China News Weekly, Issue 39, 2020

Statement: The publication of "China News Weekly" manuscript is authorized in writing