The strain mutates and recovers after recovery, and the new coronavirus that killed 780,000 people becomes more dangerous?

　　Chinanews, August 19th, over 22 million people were diagnosed! Over 780,000 people died! In the past few months, the new crown virus has spread raging around the world, and its astonishing "lethality" is worrying. Especially recently, news of this virus variant strain was discovered in Malaysia, South Korea and other places, further "stimulating" people's sensitive nerves.

　　Will the new coronavirus spread faster and more deadly after it mutates? Why does the patient have "rejuvenation" after healed? Will vaccine development be affected by virus mutation? These have become the questions that the people are focusing on and eager to be answered.

Data map: On August 14, local time, Paris was officially listed as a "high-risk area" for the spread of the new crown virus by French officials. Photo by China News Agency reporter Li Yang

Discover mutant strains and new virus lineages

"72 Changes" of New Coronavirus?

　　Recently, mutant strains of the new coronavirus have been discovered in many countries around the world. The latest case of virus mutation that has caused concern comes from Malaysia. On the 16th, Malaysia’s Ministry of Health Director Nuer stated that among the existing confirmed cases, 4 D614G mutant strains were confirmed.

　　Just the day before, the Indian media reported that Indian researchers had discovered 73 variants of the new coronavirus strain in the eastern state of Odisha. Lead researcher Dr. Das said that the researchers sequenced 1,536 samples including 752 clinical samples and finally reported two new virus lineages in India for the first time.

　　In fact, the WHO has pointed out earlier that scientists discovered the virus mutation as early as February, and the mutant strain has spread in Europe and the Americas.

　　Russia also stated at the end of June that the new crown virus circulating in Russia had a mutation, but experts believe that the mutation did not cause a major change in the characteristics of the virus.

　　Japanese experts pointed out on August 9 that a small amount of base mutations occurred in the Japanese epidemic strains, or spread from Tokyo in late June; one day later, South Korea reported that three kinds of "spike protein" mutations affecting infection were found in imported cases from abroad. case……

　　In addition, Vietnam, Iceland and other countries have reported the discovery of new coronavirus mutations.

Data map: On July 1, 2020, local time, Kuala Lumpur, Malaysia, the cinema reopened, and the audience used the automatic ticket vending machine to buy movie tickets.

Mutated viruses spread faster and more deadly?

Scientists have different opinions

　　So, will the mutation speed up the spread of the new coronavirus? A few days ago, when Malaysian officials announced the confirmation of 4 D614G mutant strains, they pointed out that the mutant strain was “10 times more infectious”, which triggered widespread discussion.

　　Sumia Swaminathan, the chief scientist of the WHO, said in July that laboratory studies have found that the mutation of the new coronavirus D614G may cause the virus to accelerate replication, spread or increase. But there is still a big difference between the laboratory results and the changes in the actual spread of the virus.

　　A few days ago, Paul Tambyah, a senior consultant at the National University of Singapore Hospital and the president-elect of the International Society of Infectious Diseases, said that there is evidence that the D614G mutant new coronavirus strain has spread in some areas while the mortality rate is decreasing. Means its lethality is lower.

　　However, a study published in the International Journal of Infectious Diseases in May showed that infection with a strain with the D614G mutation may be associated with a higher mortality rate. According to the researchers, a characteristic of the strains that cause fatal infections in European populations is that they carry the D614G mutation. But the researchers said the study lacked experimental evidence.

Data map: On August 15, local time, a citizen of San Francisco, USA, enjoyed the coolness at Baker Beach near the Golden Gate Bridge. Photo by China News Agency reporter Liu Guanguan

Rare cases of Fuyang attract attention

How long can the antibody last?

　　What is worrying is that we are not only facing the challenge of mutation of the new coronavirus. Recently, among the patients cured by the new crown in South Korea, Russia and other countries, there have been rare cases of "rejuvenation" after the patient has recovered, making the cured people worry about re-infection.

　　However, many medical experts in France believe that the new coronavirus test results of some cured patients may be related to the wrong test results; said Yves Gaudin, a virologist at the Paris-Saclay Institute of Comprehensive Cell Biology It may also be that the virus in the patient's body has not been completely eliminated.

　　In addition, the "Fuyang" case also triggered research on how long the new coronavirus antibody can exist in the human body. According to the results of a study published in July in the UK, only 16.7% of patients still had enough antibodies 65 days after the onset of symptoms.

　　Vladimir Chulanov, the chief infectious disease expert of the Russian Ministry of Health, recently said that there is no scientific data on how long the antibodies in people who have been infected with the new crown can last, and how many antibodies are produced according to the severity of the disease. But what is certain is that most people who have been sick will develop antibodies.

　　In addition, according to the latest issue of "Cell" magazine, even if no virus-specific antibody response is detected, patients with mild new coronary disease will trigger a strong memory T cell response. The memory T cell response produced by natural contact or infection with the new coronavirus may be an important immune component to prevent the severe disease caused by the new coronavirus.

Data map: Recently, at the "Gamaleya" National Research Center for Epidemiology and Microbiology in Moscow, Russia, staff demonstrated the new crown vaccine.

Will virus mutation cause vaccine development to fail?

Expert: less likely

　　In the face of many unknowns in the epidemic, vaccines have become a real "killer" to defeat the virus. So, can the vaccine under development also be effective against mutant viruses?

　　Many experts said that the current virus mutation is unlikely to cause vaccine development failure. On the one hand, the new coronavirus vaccine under development has enough sites to produce immune protection, and mutations in many gene sites will not necessarily make the vaccine invalid.

　　On the other hand, no matter how fast the new coronavirus mutates, it is also in the category of coronavirus. At present, big data research is developing rapidly. Once new mutations appear, it can quickly guide the improvement of vaccines.

　　At present, in order to control the spread of the epidemic as soon as possible, many countries around the world are accelerating the pace of vaccine research and development. Russia has registered the first new crown vaccine "Satellite V". The Prime Minister of India said that the country will mass-produce the local new crown vaccine; South Africa launched the second vaccine clinical trial on the 17th; and the Cuban domestic vaccine will soon be put into clinical testing.

　　Despite the frequent news of vaccine development, experts warned that the public should remain vigilant and comply with epidemic prevention regulations before the vaccine is officially put into use.