The New Year has brought with it the much-awaited vaccine of hope… and with that comes a sudden unspoken exemption from wearing masks or social distancing, an attitude so abominably negligent that it brought “crowded places” back into fashion, and of course…a mutated virus!
Taking the common factor out of that sentence, let’s focus on the two most important developments – The Vaccine and The Virus (2.0).
THE VACCINE OF HOPE
BNT162b2
Pfizer and BioNTech developed an investigational COVID-19 vaccine (BNT162b2) and on 20 November 2020, they submitted a request to the FDA (Food and Drug Administration agency) for Emergency Use Authorization of this vaccine in the United States. You can find the protocol used by the FDA to grant emergency use authorization here: https://www.fda.gov/media/143890/download
How does it work?
A piece of mRNA coding for the spike glycoprotein (S) antigen found on the coronavirus is packed into lipid nanoparticles and is injected into the body. Fear not! This won’t give you COVID-19, as it doesn’t have all the information required to make the complete viral protein. The same goes with the mRNA vaccine being tested by Moderna.
Next, this mRNA instructs our cells to transcribe the spike protein. Once the spike protein is synthesized, our immune cells immediately recognize its presence as an uninvited guest. The immune cells attack the spike protein and elicit an immune response that is retained in memory B cells to prevent any such infection in the future, thus providing an active immunization to prevent COVID-19.
Basically, the lipid nanoparticles are a cookbook containing only one recipe (here, mRNA) for a delicious dish- the spike protein. Due to food safety reasons, this appetizing dish is disapproved by the Food safety inspectors, who in this case, are our immune cells. The body cells are the chefs and read the mRNA recipe from the cookbook and prepare the yummy dish called spike protein. However, the inspectors i.e., our immune cells, immediately taste this dish and reject it. They ban the spike protein from ever being made and appoint certain officers called memory B cells to remember and prevent this from happening in the future as well. By doing this, the food safety officials are protecting other customers of the restaurant (our body) from infection by the spike protein.
How will it be administered?
The vaccine has been cleared for Emergency Use in the States and will be administered to individuals 16 years and older as an intramuscular shot on the upper arm. The dosing regimen is set to two doses of 30 μg each, spaced 21 days apart.
What are the side effects?
The side effects are normally the same as that produced during any immune response: fever, chills, fatigue and headache. The most common side effect reported was pain, swelling and redness at the injection site, that receded with time. There have been incidences of candidates and medical personnel experiencing severe adverse reactions after receiving the first dose, but such reactions even occurred with candidates who received a saline placebo. Thus, there was no direct evidence that it was caused due to the vaccine itself. However, the FDA warns individuals with severe allergic reactions to check the ingredients of the vaccine before receiving them and advises any candidate who has an allergic reaction to the first dose to avoid following up with a second one.
Will this vaccine change your genes?
One of the most common fears in the minds of the general public is that the mRNA will get integrated into the genome and/or interfere with the genetic make-up of the individual thus posing a risk to the progeny who will inherit it. There were also rumours flying around that mRNA vaccines causes infertility. But that is simply NOT TRUE.
Here’s why-
1) mRNA themselves are extremely fragile molecules and directly injecting them would be futile as the enzymes in our body act like killer whales and degrade them on first sight. This is why they are enveloped in lipid nanoparticles.
2) These encapsulated mRNAs are then released into the cytoplasm of the cell. The nucleus, which stores all the genetic information that makes us who we are, is completely OUT OF BOUNDS for the mRNA, and it simply does not have the machinery required to enter the nucleus.
3) Once the mRNA instructs the formation of the spike protein via translation, it is immediately degraded by an enzyme Ribonuclease (an RNase) and destroyed.
4) The mRNA vaccine for COVID-19 cannot cause infertility as the antibodies produced are completely different and do not interfere with the reproductive process.
Voila! You and your genes are perfectly safe!
All things said, it is not proved that this vaccine has no adverse or long-term effects, simply because it hasn’t been tested for the long term. Due to the global necessity for a vaccine, many many parts of the protocol of developing a vaccine were shortened or neglected even. This makes the vaccine victim to public scepticism and creates room for doubts about how the vaccine will affect our future…something that only time can tell.
THE VIRUS OF DESPAIR
B.1.1.7. Variant of Concern.
While the major part of the world was attending new year parties and rejoicing the end of the dreaded year of 2020, the citizens of the United Kingdom stayed home and prayed for better days to come. A new mutant strain of the coronavirus had been discovered that, all at once, developed at least 17 mutations, which is an unusually large number. The UK is known to have some of the largest genome surveillance systems and was able to track down this virus.
What exactly got mutated?
Out of the 17 mutations, there are 8 specific ones that are a major cause of concern as they affect the genes that encode for the spike protein- the protein used by the virus to enter into human cells. First comes the mutation named N501Y which has been selected multiple times in the population. For the geeks reading this article, this meant that the Asparagine on the 501st position of the viral spike protein was replaced by a Tyrosine and ended up changing the amino acid that binds to the human angiotensin-converting enzyme 2 receptors. In simpler words, the new strain has slightly tweaked the way it binds to its point of entry into the human body. The fact that a mutation was independently selected over and over again indicates that it is in some way, evolutionarily advantageous to the virus….and disadvantageous for us.
3-4 other mutations on the spike protein are of particular concern to scientists who worry about the detection of such mutations in developing countries that do not have the adequate surveillance systems to locate the change. This new lineage is said to be 70% more transmissible in humans.
How did such a large number of mutations come up? Aren’t mutations slow to develop?
Mutations generally take a long time to crop up and get expressed. This is mostly because many mutations are disadvantageous to the organism and are selected against. Very rarely, however, if a mutation is beneficial, it gets selected against the normal gene sequence. It is thought that the same process occurred with the N510Y mutation and it occurred in one single chronically affected patient, in whom the virus stays for long enough to develop a mutation and express it. This new lineage, which was 70% more transmissible, infected everyone who came in contact with this patient. It is highly unlikely for such incidents to occur, but well, it did.
Will these mutations render the new vaccine useless?
So far, no. The CEO of BioNTech Uğur Şahin, the company that has produced the new vaccine, remains optimistic that the vaccine will not lose its efficacy. The U.K variant differs in just 9 out of ~1270 amino acids on the spike protein. The vaccine can still successfully target the remaining ~1260 amino acids that code for the protein and induce an immune response.
So far, so good. With these bittersweet developments coming up, it is necessary now more than ever, to maintain all safety precautions so that any new variants and viral lineages do not get the chance to grow through spread through the population and cause the world to plummet into another global lockdown. We hope 2021 brings with it the hope of better days to come.
Author:
Anushree Krishnamurthy
Co-Founder at The Science Paradox
Illustrator:
Yamini Kathuria
An amateur artist and an avid reader, currently pursuing a bachelor’s degree in Psychology at Delhi University. Intrigued by our experiences, from human consciousness to the complexity of nature, she wishes to work in an interdisciplinary area where cognitive science, psychology & neuroscience meet. Her love for connecting & sharing knowledge with others makes her feel happy & content, a reason to work for ‘The Science Paradox’ magazine.