SARS-CoV-2 is already a "resident virus"

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Zhang Wenhong: SARS-CoV-2 is already a "resident virus" and vaccination becomes the only channel for the world to reopen

Reporter : Long Tuyou / Publisher : China News Network / http://news.sciencenet.cn/htmlnews/2021/3/455104.shtm / Translation, editing : Gan Yung Chyan, KUCINTA SETIA

 

Zhang Wenhong, leader of the Shanghai New Coronary Pneumonia Medical Treatment Expert Team and Director of the Infectious Diseases Department of Huashan Hospital Affiliated to Fudan University, said on 26 March 2021 that the mutation of SARS-CoV-2 is a natural law and has become a "resident virus" and vaccination has become the only channel for the world to reopen.

The "2021 Macau Respiratory Infectious Diseases Symposium" hosted by the Macau Chest Disease and Tuberculosis Association was held at the Macau Fisherman's Wharf Convention and Exhibition Center on the same day. Zhang Wenhong made a special trip to Macau to conduct academic exchanges on the prevention and control of new coronary pneumonia and tuberculosis.

Zhang Wenhong made a comprehensive review of the global anti-epidemic, treatment and vaccine research of novel coronavirus pneumonia in the past year. He pointed out that the unity of the people across the country is the basis for defeating the covid plague, and the government's governance capabilities and the cooperation of the people are the key to successfully controlling the epidemic. "The development of technology for early identification and diagnosis of viruses has given us the ability to detect cases and infected persons, and is the basis for isolating the source of infection."

Zhang Wenhong said that although targeted drugs have not made significant progress, they will eventually come out. If drugs are used in conjunction with vaccines, the mortality rate of novel coronavirus pneumonia will be greatly reduced. Virus mutation is a natural law, and the novel coronavirus has become a "resident virus" for humans. "The vaccine has become the only channel for the world to reopen.

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No new covid cases in Macau for 360 days

At the seminar, Luo Yilong, the medical director of the Concede General Hospital of Macau, and Liang Yihao, the infectious disease coordinator of the Center for Disease Control and Prevention of the Health Bureau, respectively introduced the Macau SAR's full use of the government's leadership, the participation of the whole people, and the process of fighting the epidemic together. With the joint efforts of all parties, Macau has achieved no local case reports for more than 360 consecutive days, achieving low severe disease rate, high cure rate, zero patient deaths, zero hospital infections, and zero community outbreaks.

This seminar coincided with the "World Tuberculosis Day". Cao Guoxi, chairman of the Macao Chest and Tuberculosis Association, gave a report entitled "Macau Tuberculosis Prevention and Control Achievements and Challenges". He pointed out that under the leadership and support of the SAR government , Macao’s tuberculosis prevention and control work has achieved good results, with the incidence rate showing a continuous downward trend, achieving a high cure rate and a low drug resistance rate, and has been maintained at the upper-middle level of the World Health Organization’s Western Pacific Region.

Guests such as Wan Sucheng, Minister of Publicity and Culture of the Liaison Office of Macau, Li Zhanrun, Director of Macau Health Bureau, and more than 280 medical professionals from Macau attended the seminar.

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The Lancet: Only 2.7% of Wuhan population produces effective antibodies

Reporter : Zhang Siwei / Publisher : China Science News / http://news.sciencenet.cn/htmlpaper/2021/3/202131917225292462105.shtm / Translation, editing : Gan Yung Chyan, KUCINTA SETIA

 

On 19 March, "The Lancet" published online the first long-term serological follow-up survey conducted in Wuhan by academician Wang Chen of the Chinese Academy of Engineering and other scholars, revealing the dynamic changes of serum antibodies in patients with COVID-19. The results of the survey showed that among 9542 subjects, 532 were positive for antibodies to the new coronavirus. After correction, the positive rate for antibodies in the population was 6.9%. This shows that even after the outbreak, only a small proportion of the population was infected. Among these antibody-positive people, 82% are asymptomatic infections, and only 40% have produced neutralizing antibodies (functional antibodies that can effectively fight the virus), and this part of the population only accounts for 2.7% of the Wuhan population, which is enough to explain The population still generally lacks immunity to the novel coronavirus, and it is necessary to prevent the recurrence of the pandemic.

The number of infections estimated by the seropositive rate is higher than the number of confirmed cases

This study was conducted after the unblocking of Wuhan in April 2020, selecting all 13 districts under the jurisdiction of Wuhan, and using a strict multi-stage cluster random sampling method to conduct on-site questionnaires on a representative sample of 9,542 residents from 3,556 households. And throat swab nucleic acid, serum novel coronavirus antibody test, followed by follow-up in June and 10-12 months.

It is reported that this is also the prospective long-term seroepidemiological follow-up survey with the longest observation time and the most follow-ups in the world so far.

Studies have shown that the positive rate of antibodies in women is higher than that in men, and the positive rate of antibodies in people aged 66 and above is higher than that of other age groups. The positive rate of antibodies in medical staff is higher than that in other occupations. People who have been through the hospital.

In addition, the study also found that there is a big difference between the number of confirmed cases of the new crown in various countries and regions in the world and the number of infections estimated based on the seropositive rate of the population.

In this regard, researchers believe that this is mainly because most of the new crown infections are asymptomatic infections and mild patients, plus the psychology and behavior of the infected patients, the local virus nucleic acid detection capabilities at the time of the epidemic, nucleic acid screening strategies, and nucleic acid sampling. Differences in methods and laboratory testing methods have resulted in the positive rate of antibodies being much higher than the incidence rate reported locally, and the number of infections estimated from the positive rate of seroantibodies is also much higher than the number of diagnosed cases.

"Assessing the proportion of people who are infected with the new coronavirus and who are immune is crucial to formulating effective disease prevention and control strategies to reduce the possibility of recurring pandemics in the future." Wang Chen said, because people with mild infections may not seek medical attention. Symptoms are usually not tested, and the number of confirmed cases of covid and the actual number of infections will be very different. This is also a common phenomenon in the global new crown epidemic.

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Neutralizing antibodies can be maintained for at least 9 months

It is worth noting that 437 (82%) of the 532 novel coronavirus antibody-positive persons in the study were asymptomatic, which is much higher than the estimated value of 40%-45% reported globally in the past. This also truly reflects a population infection characteristic of the new coronavirus and shows the "cunning" of the new coronavirus.

The researchers pointed out that the subjects may have recall bias when reporting whether they have had symptoms in the past 5 months, but this study will not obviously misjudge whether there are symptoms or not, because Wuhan took very strict measures to identify each case at that time. Citizens also paid great attention to recording their symptoms during the outbreak.

"If the seroconversion rate can accurately reflect the exposure to the new coronavirus, then the obvious difference between the low number of cases and the high seroconversion rate indicates that most of the seroconversion rate is anti-new coronavirus antibodies produced by asymptomatic infection. "Relevant researchers said that they use live virus micro-neutralization test methods to ensure the accuracy of neutralizing antibody detection.

The study found that in April 2020, only 40% (212/532 people) of antibody-positive people developed neutralizing antibodies (functional antibodies that can effectively fight the virus). After the dynamic follow-up, the proportion of people with neutralizing antibodies did not see a significant drop during the two follow-up periods: 45% in June 2020 (162/363 people); from October to December 2020, it was 41% (187/ 454 people). In addition, the neutralizing antibody analysis of 335 participants who participated in all three follow-ups revealed that the level of neutralizing antibody did not decrease significantly within 9 months.

Ren Lili, a researcher at the Institute of Pathogenic Biology of the Chinese Academy of Medical Sciences and Peking Union Medical College, said that the durability of the immune response to the natural infection of the new coronavirus is currently unclear. "Our research has found that the antibodies produced after infection with the novel coronavirus can persist for more than 9 months. Most importantly, we have found that the neutralizing antibodies remain stable for at least 9 months. This phenomenon is important for future precision prevention and control work. It has guiding value."

Significant milestone

"In view of the relatively small number of neutralizing antibodies produced through natural infections, this study once again emphasizes the importance of effective new coronavirus vaccine control at the population level. The extraordinary, rapid and effective control measures implemented in Wuhan may contain the virus. The spread, but also hindered the production of continuous neutralizing antibodies, thereby reducing the proportion of naturally acquired herd immunity.” During the same period, "The Lancet" was specially distributed for the research by Richard Strugnell, an internationally renowned microbiology and immunology expert. In their review article, they believe that this study has given people a deeper understanding of the natural seroconversion of people in pandemic cities, and is an important milestone in describing the new coronavirus infection and understanding the immune status of the pandemic.

However, because most of the cases are asymptomatic, the study failed to perform nucleic acid and antibody testing at the beginning of the infection, and it was impossible to determine the exact time when the research subjects were infected and began to produce antibodies.

It is reported that this research was jointly funded by the Chinese Academy of Medical Sciences and Peking Union Medical College, the National Natural Science Foundation of China, and the Ministry of Science and Technology. (Source: Zhang Siwei, China Science News)

Related paper information: https://doi.org/10.1016/S0140-6736(21)00238-5

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The Lancet: Covid patients are most prone to fatigue and muscle weakness

 

Reporter : Zhang Siwei / Publisher : China Science News / http://news.sciencenet.cn/htmlnews/2021/1/451604.shtm / Direct translation

On 9 January, a new study published by The Lancet showed that 76% of patients still had at least one persistent symptom 6 months after the onset of onset, among which fatigue and muscle weakness were the most common symptoms, sleep disorders, and anxiety and depression also frequently occur.

The research was jointly completed by Wuhan Jinyintan Hospital, China-Japan Friendship Hospital Respiratory Center, National Respiratory Medicine Center, and Institute of Pathogen Biology, Chinese Academy of Medical Sciences. Professor Cao Bin from the Respiratory Center of China-Japan Friendship Hospital, Professor Zhang Dingyu from Wuhan Jinyintan Hospital, and Professor Wang Jianwei from the Institute of Pathogen Biology, Chinese Academy of Medical Sciences are the co-corresponding authors; Huang Chaolin, Huang Lixue, Wang Yeming, Li Xia, Ren Lili, Gu Xiaoying, Kang Liang, Guo Li He and Liu Min are the co-first authors.

It is reported that this follow-up study was completed from 16 June to 3 September 2020, and 1733 patients discharged from Wuhan Jinyintan Hospital from 7 January to 29 May were selected. The median age of the patients was 57 years old, and the median follow-up time was 186 days after onset.

Studies have shown that the most common symptoms of patients with new coronary pneumonia are fatigue or muscle weakness (63%), 26% of patients report sleep disorders, and 23% of patients report anxiety or depression. Six months after the onset of onset, patients who were more severely ill at the time of hospitalization were more likely to have decreased lung function and abnormal chest imaging, which suggested that lung function had not yet fully recovered.

In addition, the study also tested 94 patients with new coronavirus antibodies in the acute phase of infection and 6 months after the onset of the disease. Compared with the acute phase, the titers of neutralizing antibodies in the patients' body dropped by more than half (52.5%) after 6 months of onset.  This suggests that patients who have been infected with novel coronavirus pneumonia may still be infected again.

Since there are currently few follow-up studies on patients with novel coronavirus pneumonia, little is known about the long-term outcome of patients with covid. Previously published new crown follow-up studies have a small sample size and a short follow-up time. The follow-up time is usually 3 months after discharge.

Professor Cao Bin from the National Respiratory Medicine Center, China-Japan Friendship Hospital and Capital Medical University said, “Because COVID-19 is a new disease, we are just beginning to understand its long-term impact on patients’ health. Our follow-up studies show that, Most patients will continue to be at least partially affected by the virus after they are discharged. Medical care after discharge is very necessary, especially for patients who are more severely ill during hospitalization. Our research also suggests that in a larger population The importance of conducting longer-term follow-up studies in order to understand the full impact of the disease on the human body."

The researchers conducted face-to-face interviews with all enrolled patients, and assessed their symptoms and health-related quality of life through a series of questionnaires. The enrolled patients also underwent physical examinations, laboratory tests, and a 6-minute walk test to assess the endurance level of the patients. Among them, 390 patients underwent further examinations including lung function assessment. In addition, 94 patients who participated in another clinical trial (LOTUS China) and completed the acute phase of the new coronavirus antibody test will be tested again during the follow-up.

In addition, the study also found that some patients have kidney problems after being discharged from the hospital. In addition to the lungs, the new coronavirus also affects other organs including the kidneys. Laboratory examination found that 13% (107/822) of patients with normal renal function at hospitalization had abnormal renal function at follow-up.

The researchers said that due to the limited number of patients who completed antibody testing during the acute phase and follow-up of the study, a larger sample of studies is needed in the future to illustrate the dynamic trend of antibody changes over time. During the Wuhan epidemic, mild patients were treated intensively in square cabin hospitals, and this study failed to enroll mild patients. Therefore, it is necessary to conduct further research to compare the long-term outcome differences between outpatient mild patients and inpatients.

In addition, because the study was unable to obtain data on lung function and 6-minute walking distance of patients with covid before infection, the abnormal lung function and exercise capacity found in the study cannot be directly attributed to the new coronavirus. In addition, due to the way the data is obtained, it is impossible to further distinguish whether the symptoms that existed during the follow-up are persistent after the onset of the disease, further aggravated after discharge, or new symptoms after discharge.

"Although the study conducted a comprehensive assessment of the outcome of patients discharged from the new coronary pneumonia, only 4% of the patients who were finally included in the analysis were admitted to the intensive care unit. Therefore, the information provided by this specific cohort study is not for the long-term outcome of patients with novel coronavirus pneumonia. Conclusion. Nevertheless, previous studies on patient outcomes after admission to the intensive care unit have shown that patients with novel coronavirus pneumonia who are critically ill during hospitalization will experience impairments in cognitive function and mental health and/or physical function after discharge. The extent is much higher than when discharged from the hospital.” said Monica Cortinovis, Norberto Perico and Giuseppe Remuzzi, experts from the Italian Mario Negri Institute of Pharmacology who were not involved in the study.

Related paper information: https://doi.org/10.1016/S0140-6736(20)32656-8