Coronavirus vaccination: Can a single shot of COVID vaccine protect you against the Delta variant? Experts say 'barely'

The second wave of coronavirus took us all by surprise and gave us no time to prepare for the devastation it caused. It taught us the importance of social distancing, double masking and the role of vaccination in curbing the spread of the virus. Now, with the emergence of new, dangerous variants, COVID-19 vaccination has become the need of the hour and until and unless we're all vaccinated against the deadly virus, there is no way we can dodge a potential third wave.

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Majority of the COVID-19 vaccines in and around the world are administered in two doses. Bharat Biotech's Covaxin and Serum Institute of India's Covishield, the two major COVID vaccines in India, also have to be administered in two doses. While Covishield's second dose can be taken after the gap of 12 weeks, you can get your second dose of Covaxin, between an interval of 4-6 weeks.

In other parts of the world, Moderna, Pfizer's mRNA vaccine is also one of the first commercial COVID-19 vaccines to be approved for use. Similar to all other vaccines, mRNA vaccines are administered to prompt a durable immune response, which is achieved through two doses.

Experts suggest that getting only one dose of COVID vaccines only provides partial immunity, which means you are still at risk of developing severe COVID infections. Given the new emerging variants, it becomes all the more crucial that you take your vaccination process seriously and follow all the guidelines laid down by health officials.

A new study on the Delta variant conducted by French researchers, published in the journal Nature found that the Delta variant or the B.1.617 lineage has mutations that allow it to evade the antibodies produced by vaccines or by past COVID infection.

Scientists believe that a single shot of vaccine "barely" offers any protection against the Delta strain.

However, the study reported that only after administering the two doses of COVID vaccines (Pfizer-BioNTech or AstraZeneca vaccine) can an individual retain significant protection against the variant.

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The team of researchers involved in the study looked at blood samples from 59 people after they had received the first and second doses of the AstraZeneca or Pfizer-BioNTech vaccines. As per reports, blood samples from 10 percent of people who had received their first dose of the vaccine were able to neutralize the Delta and the Beta variant. But it was observed that a second dose augmented the effectiveness of the vaccine against the variants.

According to the study, "A single dose of Pfizer or AZ was either poorly or not at all efficient against Beta and Delta."

Latest reports by the Centre for Disease Control and Prevention also suggest full vaccination offers a much better firewall against infection than partial vaccination.

Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, at a White House coronavirus briefing said, “Please, get vaccinated. It will protect you against the surging of the delta variant."

When it comes to COVID-19, the requirement for a booster shot is still under talks. While the mutating COVID strains only add to the woe of the people and health officials, the efficacy of booster shots and whether we need it at all requires proper investigation and evidence.

As of now, Pfizer BioNTech are looking forward to seeking federal regulatory approval for a booster shot that is said to trigger antibodies 5 to 10 times higher than the two doses of COVID vaccines.

The statement released by the company read, “We continue to believe that it is likely, based on the totality of the data we have to date, that a third dose may be needed within 6 to 12 months after full vaccination."

“While protection against severe disease remained high across the full 6 months, the observed decline in efficacy against symptomatic disease over time and the continued emergence of variants are key factors driving our belief that a booster dose will likely be necessary to maintain highest levels of protection," they added.

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COVID-19 spares no one. Considering the young and the elderly are both equally susceptible to the deadly coronavirus, each and every individual, falling under the eligibility criteria, must get themselves vaccinated. While you may not feel the need to get vaccinated given that you are young or have no pre-existing comorbidities, it is crucial that you protect the most vulnerable in society. Negligence can only lead to regret and can trigger yet another wave of coronavirus.