Hello friends. This is the question that popped in my mind when I was seeing new strains of virus arising without ceasing for a bit. So, I did some research online and here I have written everything that I have found.
Henceforth, let us hop into the discussion that why there are lots of variations of coronavirus?
But before jumping to that, let’s answer some other questions. Shall we?
When it was first scene?
It had been more than one and half a year that the fast pace of the running world was put on halt by an unwelcoming danger. Which, till this date still has the world in its grasp. It was started as a small package in China, but later came out to be a global bombardment. It was Coronavirus.
It was 1st seen in November,2019, in Wuhan, a capital of Hubei province in China which outbursted and took over the largest of the economies. The disease is named as Covid19, as the discovering year, but it is 2021 now, and the cases are still brewing on despite of the treatments and preventive measures like vaccines.
Now, back to our question.
Why so many variations?
May be the medical system in the world is frail! Well, honestly I can’t deny that, as medical development is a never ending progress. And it takes time, effort and medical knowledge to develop treatments according to that particular cause, here SARS-CoV-2 or Corona virus.
But here we are talking about one whole year to develop a vaccine while the cases are burning up.
Besides, what could be the cause of that? Well putting it simply. As we are taking measures to kill it or cure ourselves, the virus itself is taking counter measures to become ‘unkillable’.
So, do they have consciousness about that? No. So, how do they change or ‘mutate’?
First keep in mind that it’s a chance event, hence not in someone’s own strength to mutate one self.
As we may have known that each living organism has some data of itself, more like its unique identity i.e. genomic material- either DNA or RNA. Most of the organisms have DNA as their hereditary material, which they pass to their next generation. However, virus can also have RNA and in our case, coronavirus ‘has’ RNA.
Now if we are already here, why not let’s take a peek into its structure.
The RNA is enveloped by the protein, building a virus. Others are beneficiary structures like spike proteins.
- Spike protein helps virus to enter into host cells by latching with angiotensin-converting enzyme 2, ACE2.
About: ACE2-These are enzymes found on cell membranes of intestines, kidney, testes, gallbladder and heart. It converts Angtiotensin II to Angiotensin i.e. vasoconstrictor to vasodilator. Hence a beneficial drug to lower BP in cardiovascular disease.
Coronavirus RNA is made up of 30,000 basepairs(bp). What this means?
Ex.1. Imagine a very long line of human laying down head to toe to each other. Now think another line parallel to this one. Now, both of these lines, let’s say A and B, are joined by the corresponding humans, inside the lines, holding each other’s hand.
Here, hand = bp and Human body = RNA backbone.
Some of the humans belong to a same family = gene.
- So, as the virus multiplies, the parent creates copies of its daughter cells.
- The replication of genome is so fast that duplicating something this big is a miracle in itself. But once in a while there can be some variations in their gene sequence. This modification most of the time, can cause the organism, here virus, to become weak and hence can cause its own death. But sometimes, it turns out to be in favour of them like making it more transmissible.
Eg. Delta variant(B.1.617.2 carrying L452R, T478K and P681R mutations) which was 1st scene in India and later became the cause of 2nd wave of mass deaths, killing millions of people in India itself.
About: Delta variant- It has further mutated into two more variants AY.1 and AY.2 known as Delta-plus variants, carrying spike protein(K417N) mutation which was also seen in B.1.351 or Beta variant first reported in South Africa.
Considering the above ex.1., suppose some of the members i.e. nucleotide(building blocks of RNA/DNA) of a same family i.e. gene, is substituted by somewhat other one. This can either break the chain of the complimentary functionality or enhance it. And also, making the process somewhat different. So, making a different variant of the virus.
There were already alpha and beta variants detected where alpha being the 1st.
What makes the delta different is that, it is multi mutated in the gene, coding for spike protein making it more dangerous.
So the vaccines will have any affect against the variants?
For this, 1st we need to understand what vaccines are. And while doing that we will be going to dive a little into our immune system.
Vaccines are of different types: For ex:
- Inactivated vaccines: These consist of weakened viruses.
- This will not cause disease but will create an immune response. And here’s the thing comes. In our body, the 1st immune response is always weak and short lasting taking its sweet time to develop, which here is ignited by these weakened viruses already, before the 2nd infection.
- So, the 2nd time, if the actual virus enters in our body, the 2nd response will be a robust one with fast and strong response for longer duration. It happens because of memory cells, but leave it for later.
- Eg. Covaxin, developed by Bharat Biotech and Indian Council of Medical Research.
- Viral-vectored vaccines: In these, a vector carries the antigen.
- Means, a safe virus is used to carry the immune producing antigen to impart an immune response.
- The immunity will still think of it as a threat but as the virus is non-pathogenic, the symptoms will not be there.
- Eg. Covishield which is made from chimpanzee viral vector with weakened version of common cold virus, developed by AstraZeneca and Oxford University whilst in India is manufactured by Serum Institute of India(SII).
There are more types but we will be going superficially through them. They are
- Protein based vaccines, containing only the antigenic fragments without the virus itself.
- Nucleic acid vaccines(DNA or RNA), these are vaccines using genetic material of the pathogenic organism that stimulates the immune response.
So, the answer to the original question.
We will understand it by taking an example.
As it has seen that the vaccines for the B.1.617.2 are actually less efficient as the antibodies formed in the body were less able to neutralize the virus.
So it’s both yes and no.
Yes, as it might still work on the virus as the response generated in the body is a diverse one(It means that our body has many kinds of soldiers protecting the body).
No because it will be less efficient.
So the question arises now: Should I take vaccine now as for the newer variations?
The answer in short is ‘Yes’. Definitely a yes. It is true that the vaccines are less effective on the newer variations. But it doesn’t mean that the original one has been eradicated entirely from the world. Also, it might not cease the symptoms but can prevent the death though.
The research is endlessly going on. As the new variants are coming, the vaccines will be modified too. We can say that- But even so, the virus will mutate too which will create an endless cycle.
That is true indeed, but keep in mind, sometimes ago, Polio and Tetanus were fatal too. And yet they are not talked about now, thanks to the very vaccines.