A new sublineage of the Delta variant of coronavirus, called AY.4.2, has been detected in Madhya Pradesh and Maharashtra in India, according to a report released by the National Centre of Disease Control (NCDC). Additionally, AY.4 has also been detected in 1 percent of samples from Maharashtra.

The sub lineage accounted for approximately 6 per cent of all sequences generated, according to NCDC.

The variant was declared a "variant under investigation" by scientists in the UK last week, which they say is responsible for a growing proportion of COVID-19 cases, and could be more infectious than the original Delta variant.

According to a report by the UK Health Security Agency, released last week, “a Delta sub-lineage newly designated as AY.4.2 is noted to be expanding in England,” The Guardian reported.

The report states that in the week beginning 27 September, AY.4.2 accounted for about 6 percent of sequenced coronavirus cases and is “on an increasing trajectory”.

Here's what you need to know about the variant.

AY.4.2 is an offshoot of the Delta variant, containing two mutations in its spike protein, which allows the virus to penetrate human blood cells.

It was first identified in July 2021, and has been increasing slowly since then, the BBC reported.

Those mutations, known as Y145H and A222V, have been found in other variants since the beginning of the pandemic.

There is no indication so far that the new variant is more transmissible as a result of the changes in the spike protein, but it is something which is still being studied, the BBC reported.

"It's nothing compared with what we saw with Alpha and Delta, which were something like 50 to 60 percent more transmissible. So we are talking about something quite subtle here and that is currently under investigation," he said.

"It is likely to be up to 10 percent more transmissible," he added.

But it cannot be blamed for high UK COVID-19 case numbers, scientists say.

The new variant is also being closely monitored in the US and Israel, according to Business Insider.

There had been some in Denmark but new infections with AY.4.2 have since gone down, the BBC reported.

According to the Centers for Disease Control and Prevention (CDC), AY.4.2 is still "very rare" in the US.

"It is well below 0.05 percent of all our sequenced viruses, with less than 10 reported in our database so far," the CDC was quoted as saying by Business Insider.

Viruses mutate all the time, and it's not surprising to see new variants of COVID-19.

The best way to protect yourself from any COVID-19 variant is by getting vaccinated, continuing to follow safety protocols like wearing a mask and social distancing.

(With inputs from The Guardian, BBC & Business Insider.)