Decoding booster shots for COVID-19 in India

Dr Ashish Vora, Manager-KnowledgeBase and Senior Biocurator, PierianDx talks about booster shots for COVID-19 in India

As the world continues to fight COVID and its new variants on a united front, everyone’s attention is now turning towards booster shots for vaccines. Just like how booster shots are administered for other diseases like Tuberculosis, Hepatitis, and Chickenpox, we will also require vaccine boosters to put up a fight against Coronavirus. But what are booster Shots and why are they so important?

In India, the government has begun rolling out booster shots, which is a third dose of the first two primarily administered COVID-19 vaccines. Let us briefly cover the 3 main booster shots available in India.

Covaxin

The Covaxin booster dose showed promising results in its booster dose trials¹ with more than 90 per cent of all individuals boosted with Covaxin. The booster dose had efficacy being maintained for a period of 6 months. The boosted subjects showed high neutralizing activity against the Omicron variant.

Covishield

Positive results from a preliminary analysis of an ongoing safety and immunogenicity trial² showed that Vaxzevria (Covishield in India), when given as a third dose booster, increased the immune response to Beta, Delta, Alpha, and Gamma SARS-CoV-2 variants, while a separate analysis of samples from the trial showed an increased antibody response to the Omicron variant.

Sputnik light

Based on the data collected by the Spallanzani Institute and results of the previous studies³, heterologous (“mix and match”) boosting with Sputnik Light is the best solution to increase other vaccines’ efficacy and extend the booster protection period as optimal adenoviral platform configuration provides better protection against Omicron and other variants.

The recently approved Sputnik Light is based on recombinant human adenovirus (medium-sized, nonenveloped) serotype number 26 (the first component of Sputnik V). A one-shot vaccination regimen of Sputnik Light provides for ease of administration, helps to increase the efficacy and duration of other vaccines when used as a booster shot. This will further make an important contribution to the country’s vaccination program.

To provide extra security cover amid the Omicron scare, India has prioritised administering “precautionary doses” of COVID-19 vaccines to frontline workers, healthcare workers, and senior citizens with comorbidities aged 60 and above.

While booster shots have not been made mandatory in India, it is advisable to get your booster doses if you are eligible for a better immune response against COVID-19. Make sure you do not delay your booster dose registration on the CoWIN portal. Nobody is safe until we all have the opportunity to be vaccinated. While that is still in progress, everyone needs to continue to focus on other measures like mask-wearing, handwashing, social distancing, and good ventilation.

References:

1. ^{Covaxin (BBV152) Vaccine Neutralizes SARS-CoV-2 Delta and Omicron variants}
2. ^{New Vaxzevria data further support its use as third dose booster}
3. ^{Sputnik Light booster after Sputnik V vaccination induces robust neutralizing antibody response to B.1.1.529 (Omicron) SARS-CoV-2 variant}