A 63-year-old woman succumbed to the Delta Plus variant of COVID-19 in Maharashtra recently. The woman was diabetic and vaccinated with both doses of the COVID-19 vaccine. This has further raised concerns about the efficacy of vaccines against the various existing and upcoming variants. Experts believe the Delta strain was responsible for the second wave of COVID-19, which infected millions and caused the deaths of thousands.

Experts and health officials have also expressed concerns about the Delta Plus escaping immune response of antibodies against COVID-19, infecting people with the disease.

Dr Ann Mary, Consultant, Dept of Internal Medicine, Amrita Hospital, Kochi shared that antibody response could wane off by the end of six months, this has become a concern for major vaccine producers. There is ongoing research on the need for a third booster dose to enhance the efficacy of the vaccines and provide immunity against all the major variants of concern including the Delta Plus variant.

Addressing the issue of booster doses in the future, Priya Abraham, Director, National Institute of Virology, Pune has mentioned that there are ongoing studies overseas and about seven different vaccines have been tested. She also confirmed that there would be recommendations for a third booster dose in the future. 

Recently Dr Cyrus Poonawalla, Chairman, Serum Institute of India (SII), Pune along with 7000-8000 employees of SII were administered with the third dose of Covishield. Dr Poonawalla has also expressed concerns about the reduced efficacy of vaccines after six months post the second dose. 

As the Delta Plus variant is the most dominant and has spread rapidly across continents, Israel has extended its booster campaign by administering a third dose to curb the spread of this variant. Israel’s Prime Minister Naftali Bennett has also received the third shot of Pfizer/BioNtech’s COVID-19 vaccine.

In recent weeks several countries have decided to offer booster shots to older adults and citizens with weakened immunity, including the US, Germany, and France.

As the second wave has been plateauing in India, lockdown restrictions have been eased, increasing the chances of more infections. Then there are concerns of a third wave which may or may not have the devastating impact of the second wave.

Dr Honey Savla, Internal Medicine, Wockhardt Hospital, Mumbai Central, opines that vaccination is effective to protect against serious illnesses caused by this variant. However, there is a huge difference in the antibody response after vaccination in individuals especially so in the ones with comorbidities.

As further evidence and studies surface on the efficacy of vaccines on more variants of the COVID-19 virus, there may be a need for a third booster dose to help prevent serious illness and mass spread of COVID-19. But whether a third dose will be enough, or more would follow is a question only time can answer.

prabhat.prakash@mmactiv.com