Should the virus be vaccinated when it is mutated?
Generally speaking, although the toxicity and lethality of a mutated virus are not as good as one generation, its transmission and reproduction capacity in the human body are stronger than one generation. Taking the current new coronavirus (SARS-CoV-2) that has mutated into D614G, although the virus is less virulent than the original virus, its infectivity is more than 10 times.
In the United Kingdom, the virus mutated into the “B1.1.7 strain”, which also threatened young people who were more resistant to infection in the past. In Africa, the new coronavirus has mutated into the virus lineage of the “B 1.351 strain”.
Why do I need two doses?
When the mutated virus gradually spreads across the five continents, and the virus continues to mutate, although public health measures such as wearing a mask and maintaining social distancing can temporarily stop the virus from spreading, vaccination is the opportunity to achieve long-term peace and security.
At present, the world’s most popular vaccine is the “BNT162b2” vaccine from Pfizer, followed by the “mRNA-1273” vaccine from Moderna Pharmaceuticals (formerly developed by NIH of the US Department of Health), Oxford/Astertel Kang (Oxford-Astra Zeneca) “AZD1222” vaccine and Russia’s “Sputnik V” (Sputnik V) vaccine.
What they have in common is that they need two doses of vaccine. The first dose mainly provides early protection, and the second dose is enhanced protection. Most of the two doses need to be separated by about 2 to 4 weeks (Note: Oxford/AstraZeneca ( Oxford-Astra Zeneca) vaccines can be separated by 4 to 12 weeks).
What is the difference between the various vaccines?
On this issue, let’s start with the structure of human cells. There are two kinds of polymers of nucleic acids in human cells: one is deoxyribonucleic acid (deoxyribonucleic acid), which is abbreviated as DNA, which exists in the nucleus (nucleus), and the other is ribonucleic acid, which is abbreviated as RNA. There is a cytoplasm outside the nucleus.
The Oxford University vaccine is made of DNA, which is relatively stable but has many side effects, and the validity is 75%; the vaccine made of RNA has an efficiency of 95%. However, because RNA itself is an unstable nucleic acid, vaccines made of RNA are less stable than vaccines made of DNA. Therefore, if it is not refrigerated in a relatively high-temperature freezer, it is easy to deteriorate and become invalid.
Both Pfizer Pharmaceuticals and Modena Pharmaceuticals are RNA vaccines. The two are basically similar, except that the storage temperature is different. Although the former was developed and marketed first, the latter is not common because ice storage at minus 70-90 degrees is not common, so it is added The buffer material is stable and can be stored at minus -20 degrees.
The virus is always mutating, so should we get a vaccine?
Since the virus continues to mutate, and most vaccines developed in Europe and the United States are made under urgency and have not undergone the fourth phase of clinical testing, the public cannot help but hesitate whether to administer the vaccine now and whether it will become a white mouse in clinical trials. What?
Indeed, when Pfizer’s “BNT162b2” vaccine was approved for emergency use in Hong Kong in late February, according to the latest research conducted by the Faculty of Medicine of the University of Hong Kong, only 45% of Hong Kong citizens interviewed expressed their interest in vaccinating the new coronavirus. By November, about 60% became less. Among them, the younger, better-educated, and wealthier respondents are, the less likely they are to be vaccinated. The main reasons are concerns about side effects and questioning safety and effectiveness.
Although the virus has been mutating, because it comes from a common viral ancestor, it has been inherited and reproduced from the same virus generation after generation. The longer the mutation time from generation to generation, the more mutations will be changed. So before the virus has too many mutations, everyone should give the vaccine as soon as possible.
If more than 70% of people in a community are vaccinated, the effect of herd immunity can be obtained and the massive expansion of the virus can be blocked. According to current expert advice, people are still encouraged to get vaccinated, because if more people get vaccinated as soon as possible, the virus will disappear sooner.
Will the variant virus strain make the vaccine ineffective?
When the people began to vaccinate and the long-term epidemic showed a glimmer of light, in the United Kingdom at the end of December last year, a new coronavirus variant “B1.1.7 virus strain” with a 70% increase in transmission appeared, causing a pandemic in the UK. This also makes us worry about whether the new virus strain will affect the protection of existing vaccines?
The role of the new coronavirus vaccine is mainly to target the spike protein protruding on the surface of the virus. The vaccine makes the human body produce antibodies (antibody), recognize the thorny protein on the surface of the invading virus, and then combine with the body’s white blood cells to resist and phagocytose the virus.
Since the thorny protein of the virus is often changed due to mutations, it also changes the number and appearance of the thorny protein, avoiding the recognition of antibodies. Therefore, the effectiveness of vaccines developed based on the spike protein on the surface of the virus before mutation may naturally be reduced against the mutated virus and prevent infection. In this regard, vaccine experts generally believe that the variant virus strain
In the short term, it will affect the effectiveness of the vaccine. Because the virus changes to the complete failure of the vaccine, it cannot be achieved in a short time.
Therefore, the current existing vaccines can still help the human body recognize the new coronavirus and generate immunity.