Scientists in India are scrambling to understand the new "delta plus" variant but say it is too early to predict whether it could spark a new coronavirus wave.
More than 40 cases of the delta plus, or AY.1 variant, have been found across seven Indian states.
The variant – a strain of the original delta variant that led to India’s devastating second wave – contains a mutation that was also present in the South African or beta variant. This mutation – K417N – was also present in the South African variant, against which some vaccines were less effective.
While delta plus was classified as a variant of concern on Tuesday by India’s state-run genome sequencing consortium, INSACOG, scientists there said the move was precautionary.
‘No differences in transmission rate’
"As of now, we don’t see any differences in transmission between this and the delta variant. But, since all delta lineages are variants of concern, we have also labelled this one as a variant of concern," said Dr Anurag Agrawal, the director of the Institute of Genomics and Integrative Biology in Delhi.
The new variant has been identified in nine other countries, including the UK, where the first case was detected in April. According to Public Health England, 38 cases have been identified here as of June 16.
How modelled data underestimated the effect of vaccines
Francois Balloux, professor of computational systems biology and director of the Genetics Institute at University College London, said given the low number of cases reported it was impossible to say whether it was more transmissible, more lethal or if it was likely evade vaccines.
But he added: "Given that it has remained at very low frequency everywhere where it has been identified strongly suggests it is not more transmissible than its delta progenitor."
India’s second wave continues to gradually subside, and the country is currently reporting around 50,000 new daily infections. In early May, India saw a peak of over 400,000 new daily cases.
No sudden resurgence in infections in India
Doctors told the Telegraph they were yet to see a sudden resurgence in infections that would indicate the spread of a new, more transmissible variant.
"Cases have been declining and we haven’t seen a recent spike in admissions. But, we have to be vigilant, as we don’t know enough about this new variant yet," said Dr Rommel Tickoo, associate director at Max Healthcare, one of India’s leading private hospital chains.
The Indian government received heavy criticism for not reacting fast enough to warnings about the emergence of the delta variant in the spring, and it is understood the authorities will take an overly cautious approach in the future.
Local containment measures will be implemented in three of the Indian states reporting delta plus infections, including Maharashtra, home to India’s financial capital of Mumbai.
"We need to focus on these districts where the variant has been found and make sure containment measures are implemented immediately, to prevent large gatherings and aggressively test and trace," said Dr Tickoo.
"We don’t know yet as to what extent existing treatments will work against the new strain or whether the vaccine will be effective."
Only 40 samples sequenced so far in India
The Indian ministry of health has said the new delta plus is a variant of concern because it was more transmissible and binds to a receptor on the lung, but with only 40 samples sequenced in India so far, a lot more research is needed.
Scientists say that as new daily infections continue to drop there is no indication of a third wave happening yet. "It is too premature to predict a ‘third wave’ or delta plus to be a possible cause of it," said Dr Shahid Jameel, one of India’s leading virologists. "We should focus on Covid appropriate behaviour and vaccinate as much as we can, as fast as we can."
He added that with fewer than 500 samples of the new variant sequenced globally, not enough was known about it.
He added: "In India we have picked this up quickly and are tracking it efficiently."
Where is the Indian (Delta) variant in the UK?
In the meantime, Indians are being urged to adhere to Covid-19 precautions as many states gradually relax lockdown restrictions following the country’s second wave.
India’s public healthcare system is one of the most under-funded and under-staffed in the world, and another wave in quick succession could overwhelm hospitals and exhausted medical professionals.
On top of this, less than than five per cent of India’s 1.38 billion population have been fully inoculated against Covid-19 due to supply shortages and vaccine hesitancy.
Protect yourself and your family by learning more about Global Health Security