COVID-19 is a disease caused by a type of coronavirus. This illness was first found in December 2019. It has since spread worldwide.
Throughout the COVID-19 pandemic, several coronavirus variants and subvariants have emerged as the virus continues to mutate and evolve.
Many of these variants mutations have little or no effect on how the virus affects humans, but the genetic changes in the delta variant can make the coronavirus more contagious and transmittable than the original version of SARS-CoV-2.
A variant of the SARS-CoV-2 coronavirus emerged in November 2021 and it was named Omicron by the WHO.
The original omicron variant is BA.1 and the new version of the subvariant is BA.2. Omicron and other COVID viruses mutate when they infect persons and multiply copiously. Omicron, which is also known as BA.1, has generated several subvariants. The Omicron BA.2 subvariant is different from BA.1 in some mutations.
BA.2 is the most concerning. It is too early to predict what BA.2 might mean, but detecting the variants early will help health experts to better investigate that which one is most dangerous.
Studies, so far, have shown that BA.2 variant may be up to 30% more transmissible than the original Omicron BA.1.
The Omicron surge is slowing down. Infections are dropping globally. Restrictions are being
removed, but there is a new cause of concern, BA.2, a subvariant of Omicron. It is spreading
incredibly fast. In Denmark, it is now the dominant variant triggering 50,000 cases in a day for
the first time.
Reports say that BA.2 also appears to be becoming a major Omicron lineage in parts
of India, Bangladesh, Pakistan, China, The Philippines, South Africa, Germany, The United
Kingdom, and The United States.
The steady rise of the subvariant indicates that it has a growth advantage over other circulating variants. This has alarmed health authorities in several countries.
Germany says that the BA.2 could endanger the progress it has made so far. Should the BA.2 variant spread further in Germany, then it would put our success in danger.
The fails are understandable, but is BA.2 really that dangerous. Scientists are split. Some study says that Omicron subvariant BA.2 may cause severe disease, but the WHO disagrees. It says that this subvariant is certainly more transmissible, but there is no evidence to suggest that it is more lethal.
It is a variant under investigation and it is just classified right now not of concern. BA.1 and
BA.2 sub-variants are related to each other because they have a common parent that they both
were derived from, but they are slightly different from each other. International data suggest
that it could potentially have an increased advantage on the spread, but that does not seem to be any specific increase in hospitalizations or severe outcomes. It may be more subtle, but it needs to be watched, it needs to be studied.
If you have BA.2, a PCR test will still tell you that you are COVID positive. It is just not able to
detect the specific sub-variant. Sequencing is needed for that. Most people don’t really care
which particular sub-lineage of the Omicron variant they are infected with because it does not
really change what they need to be doing next.
Let’s discuss some questions that come to our mind about this new sub-variant BA.2.
What are the symptoms of the Omicron BA.2 variant?
The symptoms of the BA.2 variant are similar to those of Omicron. Whether this subvariant causes more severe symptoms is not yet known.
The common symptoms of BA.2 variant are:
Fever and body aches.
Cough and tiredness.
Drop in the level of SpO2.
Loss of taste and smell.
Difficulty breathing or shortness of breath in severe cases.
How is the Omicron subvariant different from the original?
It’s a lot more difficult to sample BA.2 subvariant. The only way is through sequencing. We no
longer have a surrogate that we had with the BA.1, which could be picked up on regular PCR.
Will the new Omicron subvariant BA.2 mean another COVID wave?
If you remember, when we had the delta variant classified as a variant of concern, we also had
several sub-lineages and people were calling them different names at that time, delta plus, and so on.
So, whenever there is a virus that evolves and develops mutations and it is different enough to
form a separate lineage like the Omicron which is a very different lineage. According to the chief scientist of WHO, the viruses continue to keep evolving, so within Omicron, you do see different patterns and from the beginning, we had recognized that the Omicron variant had BA.1, BA.2, and BA.3.
BA.1 was predominant at the beginning and still continues to be globally predominant.
BA.3 is very little, but BA.2 subvariant is increasing in some countries. There are about 30
countries that are reporting increasing rates in particularly India and Denmark, also, the UK, and South Africa. BA.2 actually seems to be actually getting an edge over BA.1 and almost
replacing BA.1. It is different in terms of some of the mutations that it has. It does seem to have
a slight growth advantage because in order to replace something, the new variant needs to have a slight growth advantage and so it has been estimated that it has a 50 or 100 percent growth
advantage over the BA.1.
Is the new Omicron subvariant more dangerous?
So, when we call something more dangerous or less dangerous, let’s try to see what exactly are
we talking about. One aspect is TRANSMISSIBILITY that we are concerned about if something is very transmissible like Omicron, means it spreads very quickly through the population.
The other aspect is CLINICAL SEVERITY. In the case of Omicron analyzing data from many countries now, it appears that Omicron causes less severe disease in the majority of people and it has resulted in fewer hospitalizations, fewer critical care, and fewer deaths.
There is a very extensive analysis in South Africa comparing their Delta wave and Omicron wave, which shows that the case fatality rate of hospitalized patients is about half during the Omicron wave.
Is it able to evade our immune responses that we have through our vaccines?
What we know about BA.2 is that it does seem to have an advantage in terms of improved
transmissibility that’s why it seems to be replacing BA.1 but it does not seem to so far cause
more severe disease or have any other major differences in properties.
The one change is that it does not have that mutation that enabled BA.1 to be picked up on regular PCR, the S gene target failure, it does not have that and therefore, the S gene in target failure can no longer be used as a proxy for the Omicron variant once it’s moved to the BA.2 subvariant.
Can you be infected with the Omicron subvariant after being infected by Omicron?
The doctors and scientists are closely looking at the data on reinfections. So, it’s too early really
to say and it is probably unlikely that that would be happening to a large extent.
Both the subvariants BA.1 and BA.2 have the properties of immune evasion, so they are able to re-infect previously infected or vaccinated people much more than previous variants could.
From past experience, we know that the antibodies that you develop will sustain for a period of
time, in fact, up to a year or so, and the fact that many people have also received vaccines either
before or after they have been infected, so what we call, hybrid immunity is considered to be the strongest type of immunity should be longer-lasting as well. It’s too early to have a lot of data on reinfection.
On long-lasting immunity, there is some data suggesting that for people who recovered
from Omicron, it is able to neutralize previous variants including Delta, but we don’t know
whether the same will be true for future variants. So, we still need to be cautious and continue
surveillance, continue monitoring and continue to be prepared to deal with new variants that are quite likely to come up frankly.
Do the vaccines work against the Omicron sub-variant?
Yes! says most scientists. Scientists say vaccines appear to be just as effective against BA.2 as
they are against other forms of Omicron. Most of the assessments so far are reassuring. It may
not be as deadly, it may not cause severe symptoms, but it is still spreading and certainly
The early studies, which were all lab-based (neutralizing antibody levels), showed that
the Omicron variant was much less able to be neutralized by antibodies compared to the Delta, and Delta was already less compared to the original strain. This created a huge amount of
concern, however, the most important is clinical effectiveness studies.
According to the clinical studies, the vaccines that we are using are still very good at protecting people against getting the severe disease. It is not only antibodies that are important in your immune system, we have a whole other part of the immune system like the T cell response, the cell-mediated immunity, which plays a very important role in preventing you from getting sick. So, the good news is that the vaccines are working very well. Almost all the vaccines that have been approved by WHO continue to work well, but we still need to develop better vaccines more broadly protective looking ahead again to see if we can protect against all coronaviruses. So, there is no need to be concerned about the existing vaccines.
Will there ever be a vaccine that can handle multiple mutations?
Scientifically, it is very plausible and possible to develop a pan coronavirus vaccine, which will
protect you very broadly.
Do the new anti-COVID pills work against the new sub-variant?
Luckily, what we know so far is that the antivirals are all working well against Omicron as
against previous variants. The antibodies are not working so well against Omicron, but the
drugs, yes, are working reasonably well.
Is it likely that COVID will keep mutating?
Yes absolutely, and we have known from the beginning that it will keep mutating. It is a
property of RNA viruses to mutate.
How severe is Omicron BA.2 sub-variant?
It is quite early to say much about it. There is not much data available about this BA.2 subvariant.
At this early juncture, the best estimates are that it is about one and a half times more
infectious or transmissible than Omicron was and remember that, Omicron was quite a bit more transmissible than Delta, which was more transmissible than Alpha.
There does not seem to be evidence that it may be more virulent than it causes any worse disease than the original Omicron strain.
We just have to be careful and keep masking up.
MEDICAL ADVICE DISCLAIMER:
This blog including information, content, references, and opinions is for informational purposes only.
The Author does not provide any medical advice on this platform.
Viewing, accessing, or reading this blog does not establish any doctor-patient relationship.
The information provided in this blog does not replace the services and opinions of a qualified medical professional who examines you and then prescribes medicines.
And if you have any questions of medical nature, please refer to your doctor or the qualified medical personnel for evaluation and management at a clinic/hospital near you.
The content provided in this blog represents the Author’s own interpretation of research articles.