If SARS-CoV-2 grabbed the headlines in 2020, 2021 has been about the emerging variants of the ancestral virus, first reported from Wuhan, China, on December 31, 2019. The Delta variant of SARS-CoV-2 had become a household name in India after the ferocious second wave. Then, Delta Plus created a few ripples and some panic before experts clarified that there is no reason to worry additionally about Delta Plus.
Then, over the last few weeks, we have been hearing about Kappa, another variant of SARS-CoV-2 being detected in one of the Indian states, and Lambda, yet another variant designated as a Variant of Interest (VOI) by the World Health Organization. It is natural to get worried after such news. But let us understand what variants are and know more about Kappa and Lambda. And, then decide if we should worry.
WHAT IS A VARIANT?
Viruses keep changing over time and this is applicable for SARS-CoV-2 too. As part of routine replication process in any virus, some changes in the genetic sequence happen, and these changes are known as mutations. Most of these mutations are not relevant and do not alter the characteristics or properties of the virus. However, of the many such mutations, a few may affect the virus’s ability (a) to spread or transmit; (b) to cause severe disease; or (c) its performance against vaccines, therapies, diagnostic tools, and other public health and social measures. If any such mutation happens in SARS-CoV-2 with properties that are under investigation and not yet scientifically proven, they are called Variants of Interest or VOI; and when the properties are proven, they are termed Variants of Concern (VOC).
In late 2020, a few mutations in the SARS-CoV-2 were reported from different countries, which had the ability to change the properties of the ancestral virus. These variants posed some level of increased risk at a global level. Over a period of time, the SARS-CoV-2 variants have been labelled VOIs and VOCs. Globally, the World Health Organization (WHO) classifies the potential VOIs or VOCs and assesses them based on the risk posed to global public health.
There are established scientific nomenclature systems for naming and tracking variants. However, in public discourse, these variants were initially being referred to using the name of the country from where they were first reported. In late May 2021, WHO-led group suggested easy-to-pronounce and non-stigmatizing labels for these variants, using Greek alphabets. (Table 1)
This process of designating a variant VOI or VOC is dynamic and based on continuous risk assessment. A variant can be upgraded or downgraded to different categories based on most recent evidence and risk assessment. At present, there are four VOCs and four VOIs at global level. Three former VOIs have been downgraded to the group ‘Alert for further monitoring’. (Table 1). In addition to WHO, a national government can also designate the variants of local interest/concern, for the country. India, for instance, named Delta Plus a Variant of Concern; however, at the global level, it is not considered a separate variant.
WHAT IS THE KAPPA VARIANT?
Kappa is not a new variant and is already designated a Variant of Interest since April 2021. However, it was back in the news in the second week of July, when two cases were reported from the genomic sequencing data of an Indian state.
Kappa is a sub-lineage of B.1.617 variant, first reported from Maharashtra, India, in October 2020. This variant was subsequently identified as a triple mutant by the Indian government in late March 2021, as it had three mutations of interest.
The sub-lineage B.1.617.1 is now known as Kappa while B.1.617.2 is known as the Delta variant. The Delta variant is responsible for the emergence of the second wave in India; it has been found in nearly 100 countries and is a global VOC. The third sub-lineage, B.1.617.3, has not been identified either a VOI or a VOC.
In simple terms, Kappa is a sibling of Delta. However, as in a family, siblings could be very different from each other, and that exactly is the case with Kappa and Delta. While Delta variant has higher transmissibility, documented immune escape and breakthrough infections, none of these properties have been documented for the Kappa variant, so far. Kappa variant is not a major concern as of now.
WHAT IS THE LAMBDA VARIANT?
Lambda variant (C.37) is in the news because it is the seventh and the latest VOI to get designated by the WHO on June 14, 2021. However, since three erstwhile VOIs have been downgraded, Lambda is among four current Variants of Interest. The variant was first reported from Peru, possibly as early as December 2020. At present, it is the most dominant variant in Peru (around 80 per cent of all cases in the country) and Chile and is widely circulating in South America. By June 2021, it had been reported in around 25 countries, including in the UK, France, Germany, Italy and Australia. However, the number of COVID cases as a result of this variant outside South America remains small. No case of Lambda variant has yet been reported from India or neighboring countries.
WHAT DOES IT ALL MEAN FOR YOU AND I?
The designation of a variant as VOI or VOC is an important part of the global response to the pandemic. However, no matter which variant it is, there is no change in the recommended measures to prevent SARS-CoV-2. Most of the currently licensed vaccines are effective against these variants. Therefore, it is important we get vaccinated. Kappa is not a cause of immediate concern and there has not been any documented change in the properties of virus; therefore, you don’t need to panic. Lambda variant has not been reported from India; however, Indian government should keep an eye out by stepping up genomic sequencing.
Epidemiologically, there is a real possibility of a third wave in India and it is possible that if a new variant emerges, the third wave could arrive early. At the citizen level, we must keep following COVID- appropriate behaviour, which includes wearing face mask, maintaining physical distancing, washing hands and getting vaccinated. That’s how we fight the virus and reduce the impact of any subsequent wave, as and when that happens.