Cat and mouse game to contain mutant viruses

On February 2, Naples, Italy, the school was closed due to the epidemic, and high school students could only take classes online on the street

After the outbreak of the new crown epidemic at the end of 2019, most people placed their hopes of ending the epidemic on the development and popularization of vaccines. Unexpectedly, just as the global vaccines were launched successively, the new coronavirus variants that appeared in the United Kingdom, South Africa and Brazil began to replace other strains that were circulating.

The sudden deterioration of the situation has forced vaccine regulators and manufacturing institutions to consider how to deal with this possible situation-the effect of vaccine doses is always unable to keep up with the resistance of new variants of vaccines. If this is the case, then vaccine manufacturers and drug regulatory agencies can only formulate countermeasures to turn vaccine research and development into a cat and mouse game.

Reference flu vaccine
Worry predictions often come true. Only a few weeks after major vaccine manufacturers obtained drug regulatory safety approvals, the emergence of virus variants forced scientists to re-test the indicators of the new coronavirus vaccine and began to worry about the actual effect of the vaccine that did not meet expectations.

On January 30, Denver, USA, staff work in the COVID-19 vaccination station

At the same time, the regulatory authorities are also actively considering how to speed up the new approval process, considering whether they can refer to the influenza vaccine model and promptly authorize vaccines adjusted and optimized due to virus variants to enter the market.

At present, the scientific community still believes that the existing vaccines are highly effective against the highly transmissible viruses that have been confirmed in the UK and South Africa. Preliminary tests at the University of Texas in the United States showed that the vaccine jointly developed by BioNTech Biotechnology and Pfizer still has a non-negligible anti-epidemic effect against the virus variants that appeared in the United Kingdom and South Africa.

However, the vaccine has not been proven to work with all mutations in the virus variants. What’s more, some mutations will continue to change further. Andrew Pollard, director of the Harvard Vaccine Group, warned of this overconfidence in the scientific community: “There may be more mutations in the future. We will eventually find that we have nowhere to escape.”

Andre Zaru, CEO of Green Light Biotech, who developed messenger RNA vaccines, also believes that new vaccines need to be tested to prepare for the uncertain future of virus variants. He said: “You need to be prepared to deal with things. In the face of new mutations, you have the leeway to choose a more wise move.”

As the first manufacturers to market the new coronavirus vaccine, BioNTech/Pfizer and Modena have a good self-positioning in the crisis management of virus mutations. Messenger RNA technology enables vaccine production companies to implant genetic codes that are adjusted as needed to deal with any changes in the virus. The BioNTech biotechnology company even claims that they have the ability to produce a new vaccine within 6 weeks.

Paul Duprex, director of the University of Pittsburgh’s Vaccine Research Center, said that the “sweetness” of messenger RNA is that it “treats people as factories” to produce the proteins needed to trigger a viral immune response.

For other vaccine manufacturers that rely on different technologies, its production will take longer. Pollard said that it may only take a few days to design a new formulation of the adenovirus vector-based Oxford/AstraZeneca vaccine, but it takes much longer to put it into production.

He explained: “The time-consuming process is the production process. You need to make new seeds, put the new seeds into the production equipment, and then make millions of doses of new vaccines.”

According to the estimates of health care analyst Jeffrey Poggs, as far as messenger RNA vaccines are concerned, the entire process from the production of a new version of the vaccine to the approval of vaccination takes 3 to 6 months; while the adenovirus vector vaccine requires 6 To 8 months; recombinant protein vaccines may take up to 9 months.

In the previous process of manufacturing recombinant protein vaccines, the French pharmaceutical company Sanofi, which suffered from Waterloo due to insufficient immune response in the elderly, stated to the outside that they will take a longer time and more steps than the development of messenger RNA methods to develop research and development. A vaccine that can cover new strains of virus.

/ The beauty of messenger RNA is that it “treats people as a factory” to produce the proteins needed to trigger the immune response of the virus. /

Its target will be on a new strain of coronavirus. Those vaccines that rely on the use of inactivated viruses or debilitating viruses, such as those produced by China National Pharmaceutical Group and China Kexing, also need longer time to adapt.

On January 13, Saint-Etienne, France, medical staff guide the public to test for the new crown virus

In addition, the length of time from vaccine production to vaccination also depends on the regulatory agency’s requirements for approving a modified version of the vaccine. The European Medicines Agency stated that it has been actively discussing the requirements for approval. The U.S. Food and Drug Administration said that it still needs to observe whether the virus mutation will reduce the effectiveness of the vaccine.

However, they all believe that the flu vaccine approval mechanism (which will be modified and adapted every year according to the most prevalent flu strains of the year) can provide a reference for the rapid approval of the new crown vaccine in the future.

Angela Rasmussen, a virologist at Georgetown University in the United States, said: “Every year we fast track influenza strains and modify the influenza vaccine approval process. We don’t need to do large-scale clinical trials to ensure that they are effective. However, this is also because The flu vaccine has been around for much longer than the new coronavirus vaccine.”

In the usual trials, the effectiveness of the vaccine is judged mainly by whether the vaccine participants are less likely to be infected than those who received the placebo. To skip this step, scientists generally need fairly reliable immune system markers to assess whether a person has enough resistance to deal with the disease.

Rasmussen said that, in short, it is how many antibodies are needed to defend against the virus.

Will the universal coronavirus vaccine arrive?

Peter Hotters, a vaccine expert at Baylor College of Medicine, said that the US Food and Drug Administration should provide more clear information on what projects the adjusted vaccine needs to be approved before it can be approved, so as to reduce unnecessary duplication of work by R&D companies.

He said that in the long run, we need to invent a universal coronavirus vaccine to solve this problem: This universal vaccine is designed to produce at least certain levels of the entire coronavirus family including SARS coronavirus and Ebola virus. Degree of anti-epidemic effect.

The National Institutes of Health recently invited research experts to apply for funding to develop a vaccine to deal with the coronavirus that has developed into a pandemic. But this is undoubtedly a huge challenge. After all, many scientists have been trying to develop a universal flu vaccine for decades. Although there have been breakthroughs, they all ended in failure.

If the new coronavirus continues to mutate in the future, which may reduce the effectiveness of vaccines, companies that research messenger RNA technology will have a huge advantage in the vaccine market estimated to be worth more than 10 billion US dollars each year.

Today, more than 50,000 cases of new crowns are routinely tested positive every day in the UK. Even though schools at all levels are closed during the holidays, in London, the number of infected people is still rising; in the east and southeast of England, the number of infected people in areas where the epidemic has eased remains high. The long-awaited full lifting of the ban was once again postponed.

Isolation measures are essential
Currently, the total number of infections treated in hospital isolation has exceeded the peak in April 2020. Jeremy Faral, director of the Wellcome Foundation and epidemiological consultant, pointed out that the UK has reached a dangerous stage in which its national health insurance system is on the verge of collapse, and an unbearable situation has emerged in many aspects.

Even the medical staff who are key workers have come forward to appeal to help promote vaccination. Most of them are also exhausted, and most of them are either quarantined or become sick from overwork. The current hierarchical management system has not changed the situation of the epidemic.

On January 2, the London government announced that it would close all local primary schools

/ The approval mechanism for influenza vaccines can provide a reference for the rapid approval of new coronavirus vaccines in the future. /

The severity of the situation has made national controls including school closures imperative. Jeremy said: “We will spend two or three months worse than March and April last year. Schools may continue to be closed until February, which will also lead to the spread of new variants of the virus among young people. Let the school become an important source of communication.”

Jeremy has repeatedly opposed “vaccine nationalism” or “vaccine classism” and called for a fair distribution of vaccine supplies and first distribution to those who need it most.

The reality today is that the virus has spread very rapidly, and in addition, 50% to 70% of the new variant combinations appearing in the UK have higher transmission, requiring stricter controls across the UK than in early December 2020.

Blockade and quarantine can “siege” viruses that humans come into contact with, and give people a breathing space. Before the virus spreads further, it is necessary to speed up the promotion of vaccination and create a suitable testing system and school operation methods.

On February 2, Brussels, Belgium, the first local COVID-19 vaccination center began operations

The tug-of-war between vaccine immunity and virus mutation is unprecedentedly tense. At present, the United Kingdom has adopted a pragmatic strategy-to postpone the second shot of the vaccine, in order to achieve more people get the first shot of the vaccine. At the same time, those virus variants with stronger transmission, even if they are not more harmful than the original virus, still need to be paid attention to in order to accelerate the optimization of treatment methods and care in human society.

Isolation measures are essential. A recent analysis by Imperial College London shows that if the United Kingdom is closed for a week before the first wave of the epidemic in the spring of 2020, then the United Kingdom will be able to reduce the deaths of about 16,000 to 37,000.