A potential disruption has recently emerged in many parts of the world, in the form of a new family of COVID-19 sub variants, being dubbed as the ‘FLiRT’ variant. As per the Centers for Disease Control and Prevention in the US, this Omicron offshoot which is being called FLiRT is based on the technical names for the amino-acid mutations, i.e. amino phenylalanine (F) replaces leucine (L), and arginine (R) is replaced by threonine (T). 

In particular, KP.2 which is one of the several variants being referred to as ‘FLiRT variants’, is dominating the COVID-19 infections lately. While medical experts in the US are not raising much concern over this new development, the government in Singapore has issued a health advisory asking people to wear masks again.

According to news reports in India, infections have recently become dominant in Maharashtra with over 70 per cent of samples tested for genome sequencing found to have KP.2 variant, with the reports having been shared with the central and state health departments for further action.

If we consider this new situation to be a ‘summer wave’ of COVID-19, one does wonder if another shot of vaccine would be required to calm this down. Amidst this uncertainty, another round of news is flashing that multinational pharmaceutical company AstraZeneca is withdrawing sales of its COVID-19 vaccine globally, since there is a surplus of more updated vaccine options that target new variants of the virus.

While the company states that this is a business decision, a response to the declining sales of the older vaccine since other options are more relevant, it comes at a time when the vaccine has come under scrutiny for causing side effects.

Researchers have found that the AstraZeneca vaccine, sold in India under the brand name Covishield by Pune-based Serum Institute of India (SII), is linked to  Vaccine-Induced Immune Thrombocytopenia and Thrombosis (VITT), a blood clotting disorder. According to the scientists from Flinders University in Australia, who recently shared their study in the New England Journal of Medicine, VITT emerged in 2021 during the pandemic, particularly after the use of the Oxford-AstraZeneca vaccine, which is based on adenovirus vectors.

According to media reports, soon after AstraZeneca announced the global withdrawal of its COVID-19 vaccine, SII gave the statement that the firm had stopped the manufacturing and supply of additional doses of Covishield since December 2021. In fact, to shift the focus from these ongoing concerns on the COVID-19 vaccine and its related side effects, AstraZeneca has apparently gone ahead to announce the launch of a new COVID-19 prevention drug.

Covaxin is also under the scanner, based on a recent study by Banaras Hindu University (BHU). Nearly one-third of the individuals who received Bharat Biotech's Covaxin reported 'adverse events of special interest,' or AESI, according to a one-year follow up study conducted by a team of researchers at BHU.

Nearly 50 per cent of 926 participants in the study complained of infections during the follow-up period, predominated by viral upper respiratory tract infections. 

In response to these findings, the Hyderabad-based vaccine manufacturer found this study to be inconsistent, marred by lapses. Bharat Biotech has been asserting that its COVID-19 vaccine has demonstrated ‘excellent safety track record’ in several studies.

After reviewing multiple cases of side effects post vaccination, doctors in India have been urging the government to review the science behind all the COVID-19 vaccines, including Covishield and Covaxin.  

An active surveillance and monitoring mechanism appears to be a ‘need of the hour’ to ensure vaccine adverse events are identified as early as possible, and not ignored.

Dr Manbeena Chawla

Executive Editor

(manbeena.chawla@mmactiv.com)