- James Gallagher
- BBC Health Science reporter
Image source,Getty Images
With the loosening of the epidemic prevention measures in England, nightclubs reopened for business.
Are people in the UK in danger of creating mutations in the new coronavirus? Will the new mutation weaken our vaccine protection? Is it important to ask these questions now?
The British government’s policy of relaxing epidemic prevention restrictions as scheduled has caused controversy among all parties. Some scientists have warned that this move creates perfect conditions for the spread and mutation of the new coronavirus. It is estimated that the number of daily viral infections in the UK this summer may reach 100,000, and many people have not had time to inject at least two doses of the vaccine.
So far, it has been the mutations that have been spreading significantly faster that have caused the problem. For example, the Delta mutation (Delta), which was first discovered in India, may spread twice as fast as the new coronavirus that first appeared in China. But the fast spreading speed is not the only characteristic of the new coronavirus.
As more and more people become more immune through vaccination and infection with the new crown, the virus has also begun to evolve its own way to evade immunity-the so-called “immune escape.”
Dr. Aris Katzourakis, who studies virus evolution at the University of Oxford in the UK, said: “We may be in the high-incidence stage of virus evolution and the worst time for immune escape in the UK.”
“The UK is in a state where it is very prone to virus mutations. But we don’t know if it will happen, but it is now more likely than ever that there will be virus mutations in the UK.”
Two things need to be considered: 1. What is the chance of virus mutation? Second, how much advantage the virus will gain by avoiding the immune system.
Immune escape
Chance is a numbers game. The so-called mutation is an error that occurs when a virus invades the body’s cells and replicates thousands of itself at will. The more times the virus is infected, the greater the chance of getting stronger mutations by chance.
How strong the virus is depends on how strong people are.
At the beginning of the epidemic, there were many viruses everywhere, and there were many opportunities for mutation. However, there is no benefit in immune escape, because not many people have immunity.
In the future, when most people gain a certain degree of immunity from infections or vaccines, mutations will greatly benefit the virus.
Image source,Getty Images
Will there be a virus mutation that is better at avoiding vaccines and immunity in the UK?
However, all of these immunity or vaccine protection should reduce the infection rate, so that the virus has little chance to mutate.
Therefore, in the field of virus system dynamics, the combination of virus transmission mode, our immunity and evolutionary biology shows that the outbreak point occurs at the moment when there is both partial immunity and enough virus to spread.
And this moment may be now: about 70% of adults and very few children in the UK have received two doses of the vaccine. Data from the UK National Bureau of Statistics shows that one in 80 people is infected.
This does not mean that a new mutation is destined to appear in the UK in the next few weeks. It is just that under the evolutionary pressure of the virus, the chance of mutation appears greater than before.
Dr. Cazorakis said: “I hope that mutations will not occur, but this is a big gamble. If our existing precious vaccines are breached, I can’t imagine what the world will be like.”
Closely
In fact, virus mutations that are better at evading vaccines have emerged. They will not completely offset the protective effect of the vaccine at once, but will gradually weaken the protection of the vaccine.
This can already be seen in the delta mutation. Almost all infections in the UK are infections of delta mutations, and this mutation is better at causing re-infection and evading the protection of vaccines, especially among those who have only received one dose of the vaccine.
Professor Jonathan Ball of Virology at the University of Nottingham said that when only part of the population is immune, especially when the virus is still circulating, only some people are immune, which stimulates the virus to develop in the direction of immune escape. And this is an inevitable trend.
“But it’s not clear yet: what does this mean in the end.”
Laboratory studies have shown that, so far, the Beta mutation (Beta), which first appeared in South Africa, has the strongest ability to evade the immune system.
However, vaccines still maintain their advantages in the real world. Studies have shown that vaccines provide more than 90% of the protection, so that infected people do not need to be hospitalized.
In addition, the virus is not invulnerable in all respects. The choice of viruses in the evolutionary process means that they may have to sacrifice certain characteristics in order to better evade the immune system.
The virus uses its “spike protein” as a key to open the door to our body cells. But it is through the “spike protein” that our human immune system learns to recognize viruses. Therefore, mutations that change the shape may help the virus evade the immune system, but also make it more difficult to infect our cells.
Professor Ball said: “Will there be a virus that can evade vaccines well, spread quickly, and make people who have received two doses of the vaccine become severely ill? It’s unlikely.”
“What makes me feel at ease is the truth. I don’t think things will be too bad.”
However, the emergence of any new mutations in the coming months will be monitored very closely.