Mutation of Delta Variant Concerning Global Experts

Variants of the SARS-CoV-2 virus have been of significant concern to public health experts since the start of the pandemic. Initial variants, like the UK and South African strains, have caused additional outbreaks of COVID-19 around the globe.

One of the most recent variants, the Delta variant, is now one that is worrying experts the most.

The strain initially began in India, where it caused one of the worst outbreaks of infections the world has seen to date.

The United States Centers for Disease Control and Prevention (CDC) recently upgraded the Delta mutation to a classification of a "variant of concern”, where it was previously a “variant of interest.”

A “variant of concern” is defined by the CDC as “a variant for which there is evidence of an increase in transmissibility, more severe disease (e.g., increased hospitalizations or deaths), significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures.”

The variant has made its way across the west, with it now becoming the dominant strain in the United Kingdom.

Luckily, COVID-19 vaccines still appear to be effective against it. A recent study conducted by Public Health England demonstrated that the Pfizer vaccine was 88% effective against symptomatic disease from the variant 2 weeks after the second dose, compared to 93% effectiveness against the UK variant.

Likewise, the Astra Zeneca vaccine showed a 60% efficacy against symptomatic disease from the B.1.617.2 variant compared to 66% effectiveness against the B.1.1.7 variant.

However, public health experts have now identified a variant of the Delta strain, which is being called “Delta Plus”.

Cases of the Delta Plus variant have now been identified in multiple countries, including the US, Canada, India, Japan, Nepal, Poland, Portugal, Russia, Switzerland and Turkey.

Three worrying characteristics of the Delta Plus variant have been identified, which include increased transmissibility, stronger binding to receptors of lung cells and the potential reduction in monoclonal antibody response.

“If we go by the currently available evidence, Delta plus is not very different from Delta variant. It is the same Delta variant with one additional mutation,” Chandrakant Lahariya, a physician-epidemiologist and vaccines and health systems expert based in New Delhi said. “The only clinical difference, which we know till now, is that Delta plus has some resistance to monoclonal antibody combination therapy. And that is not a major difference as the therapy itself is investigational and few are eligible for this treatment.”

The World Health Organization (WHO) stated that it is tracking recent reports of the Delta Plus variant. Experts advise the public to remain following COVID-19 restrictions and to get vaccinated as soon as possible if not inoculated already.