Delta Plus: What does ‘variant of concern’ mean?

According to Centers for Disease Control and Prevention (CDC), a US government interagency group developed a variant classification which includes the following three categories:

*Variant of interest
*Variant of concern
*Variant of high consequence

A ‘variant of concern’ is one for which there is evidence of an increase in transmissibility, more severe diseases that require hospitalisation or death, a significant reduction in neutralisation by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures, mentions CDC.

In the case of the Delta Plus variant, the Health Ministry identified three characteristics — increased transmissibility; stronger binding in receptors of lung cells; and potential reduction in monoclonal antibody response.

‘Variants of concern’ include B.1.1.7 or Alpha first identified in the UK, B.1.351 or Beta first identified in South Africa, and B.1.427 or Epsilon first identified in the US. Earlier, World Health Organisation (WHO) had identified the Delta variant or B.1.617.2, first found in India, as a ‘variant of concern’.

How can a variant of concern be controlled?

They require appropriate health actions like increased testing or “research to determine the effectiveness of vaccines and treatments against the variant”. “Based on the characteristics of the variant, additional considerations may include the development of new diagnostics or the modification of vaccines or treatments,” CDC further reads.