India is grappling with the second wave of the COVID-19 Pandemic. We reported 259,551 new cases on Thursday(21st May), to take the total count of cases to 26,031,991. In the midst of this, the vaccine seems to be the only ray of hope.
Perhaps the most pressing issue right now is if these vaccinations will protect against the latest COVID-19 strains, or whether more booster shots will be needed. Viruses, as we all know, are continually evolving. Occasionally, they mutate to the point that vaccines are made ineffective.
More research is required to determine if a third anti-COVID-19 booster dose would be more effective in combating the country's outbreak of infections, as the recommendation is currently focused on speculation, according to health experts.
What is a Booster Dose?
A booster shot is a second dose of a vaccine that is given to increase immunity. You would be better protected from illness as a result of this. However, with regards to the COVID 19 vaccine, a second dose is a must. A booster shot in this context would be taken a few months after the second jab as an added precaution.
To gain immunity, many routine vaccines need more than one shot. The MMR (measles, mumps, and rubella) vaccine, for example, needs two doses. Because certain people do not develop total immunity to an infection after one dose, the second dose ensures that nearly everyone who has been vaccinated has complete immunity.
Some vaccinations, such as DTaP (diphtheria, tetanus, and pertussis), necessitate a booster shot since the first shot's safety wears off with time. The booster shot aids in re-increasing immunity levels.
The booster shoot can happen at any time. Some vaccinations necessitate a booster shot weeks or months after the initial vaccination. Some booster shots, such as MMR and DTaP, are administered years after the initial vaccination.
What do we know about the COVID Vaccine Booster dose?
People who have received both doses of the Pfizer BioNTech vaccine or Moderna vaccine will likely require a booster shot this year and will need an annual shot thereafter, according to Pfizer and Moderna.
In February, Johnson & Johnson CEO Alex Gorsky told CNBC that people would need to get vaccinated against Covid-19 on an annual basis, similar to how they get the seasonal flu vaccine.
Bharat Biotech, the manufacturer of Covaxin, has started administering a booster vaccine after six months of the second dose. According to PTI, the company was given permission to conduct booster dose trials by the Drugs Controller General of India's (DCGI) subject expert committee (SEC). The panel also requested that Bharat Biotech send specifics of the primary and secondary goals, as well as several tests to be performed on the participants.
People in India who are fit for inoculation are currently given Covaxin and Covishield by the Serum Institute of India. Both vaccines are administered in two doses separated by at least eight weeks(now increased to 6 months).
Why is a booster dose of vaccine required?
The longer the virus is allowed to wreak havoc in India, the more people it will infect and the more likely it will evolve into new mutations.
Scientists say the new Indian "double mutant" strain has characteristics that make it more contagious and less vulnerable to vaccine-induced immunity, and we might see the virus mutate, even more, making the current batch of vaccines even less successful.
As new variants appear, booster shots will likely be needed to retain our current levels of defense or to combat new variants.
How long does protection from a COVID vaccine last?
Another problem is that we do not know how long a COVID-19 vaccine can provide safety. The majority of experts agree that security will last at least six months, but only time will tell, and further study is needed.
According to a study conducted by Pfizer and released on April 1, 2021, the vaccine provided 91.3 percent safety against COVID-19 from seven days to six months after the second dose, based on data collected from 927 individuals.
The organization is also testing the efficacy of a third dose of the vaccine, which acts as a booster and is administered six to 12 months after the second dose. The research is part of Pfizer's drug development plan to see whether a third dose of the same vaccine is successful against emerging variants.
For the Oxford-AstraZeneca vaccine(which is the same as Covishield), there is less information available. When looking at the effectiveness of the vaccine after administering the two doses at various times, studies have shown that for those who had a dosing period of 12 weeks or longer, the vaccine efficacy reached 82.4 percent after a second dose, implying that if the two doses are provided at least three months apart, they provide more than 82 percent protection.
While more data is required, it is fair to believe that the defense will last at least three months after the second dose.
Is a third dose needed?
When it comes to the applicability and efficacy of a third dose, experts say more research is needed to see if it can help combat infections more effectively, particularly in light of the raging second COVID-19 wave.
If companies decide to offer a third booster dose after two doses, according to Samiran Panda, Director of the ICMR National AIDS Research Institute, it should be focused on data on immunological memory.
This means that after two doses, what is the status of antibody concentration and after how long does it fall below a level where the third booster dose is needed, he explained.
"So we don't have enough data and I think the proposal for the third dose is based on a conjecture rather than the time that needs to lapse after which we will have data on how many shots are needed. So the time has not come as yet," Panda told PTI.
How will boosters work?
Immune booster shots act as a wake-up call for your body. Vaccines stimulate the body to produce antibodies capable of recognizing the coronavirus and, if you come into contact with it, killing it and any infected cells, normally before you notice any symptoms.
After that, memory T and B immune cells patrol the body in case there is another encounter. As the number of these memory cells decreases over time, the immune system can “forget” how to effectively recognize the pathogen or germ causing the illness in the future.
Booster shots help the immune system remember how to recognize the pathogen that is causing the disease. It means that after a booster shot, the body is more likely to react quickly and effectively.
Booster shots will be needed, according to Pfizer CEO Albert Bourla. On April 16, while speaking with CVS Health, an American healthcare firm, Bourla said, "There will be likely a need for a third dose somewhere between six and 12 months [following the first two doses] and then from there, there will be an annual revaccination."
Can boosters protect us from new variants?
New coronavirus strains are surfacing all over the world. Only a few are “variants of concern” – those that may carry mutations that enable them to avoid vaccine-induced immune responses. Third vaccine dose can also help the body recognize new coronavirus variants by stimulating the immune system.
Concerning variants include those that have appeared in recent months in South Africa, Brazil, and India (the vaccines appear to be effective against the UK variant). Mutations in the spike protein (the part of the virus that binds to human cells) can make these variants more difficult to recognize by immune cells produced by vaccines.
If these variants become dominant or more common, booster shots to protect us from them would most likely be needed. Manufacturers claim that if vaccines need to be tweaked to be more successful against new variants, they would be simple and take less than three months.
Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, clarified whether the third booster shot for COVID 19 would be required, and it more or less sums everything up. He said, "The bottom line is, we don't know if or when we will need booster shots, but it would be foolish not to prepare for the eventuality that we might need it."