Bengaluru: India on Tuesday declared a new coronavirus variant 'Delta plus' to be of concern, and said nearly 40 cases have been detected in three states.
Around 40 cases of the Delta plus variant, classified as a variant of concern (VOC), have been detected sporadically in Maharashtra, Kerala and Madhya Pradesh, the Union Health Ministry said on Wednesday.
Delta variant as well as all Delta sub-lineages including Delta plus are classified as VOC, it said. The ministry said Delta plus showed increased transmissibility and advised states to increase testing.
"As of now among the samples sequenced (45000+) in India, Delta plus variant -- AY.1 --has been observed sporadically in Maharashtra, Kerala and Madhya Pradesh, with around 40 cases identified so far and no significant increase in prevalence," the ministry said in its statement.
These three states have been advised to strengthen surveillance and take appropriate public health measures.
A Variant of Concern
After the report of AY.1 by the Public Health England (PHE) on June 11, retrospective analysis of samples revealed the first occurrence of this lineage from a sample collected from Maharashtra. The sample was collected on April 5.
As of June 18, 205 sequences of AY.1 lineage was detected worldwide, with the USA and the UK having over half of the known cases, the statement said.
INSACOG had recently identified a viral variant (delta, B.1.617.2). This viral variant has also been seen in nine other countries of the world. INSACOG is an Indian consortium of 28 labs, established by the Government of India to carry out genome sequencing of the virus causing the COVID-19 pandemic.
The World Health Organisation has introduced a classification as VOC (variant of concern) and VOI (variant of interest), with the evolution of several variants around the globe. Delta variant as well as all Delta sub-lineages including Delta Plus are classified as VOC, the statement said.
The Indian SARS-CoV-2 Genomic Consortia (INSACOG)reported the evolution of Delta plus variant (B.1.617.2) + K417N lineage of SARS-CoV2 called as B.1.617.2.1/ AY.1.
The Delta plus variant B.1.617.2.1/ (AY.1) is characterized by the K417N mutation in spike protein, the statement said.
The spike protein aids the virus to gain receptor-mediated entry into human cells. K417N corresponds to the change of amino acid lysine (K) to asparagine (N) at the 417th position of spike protein. There are other Delta plus variants with other mutations.
The AY.1 is the most well-known, but these are not identical. A second clade found in sequences uploaded to GISAID from the USA, is now designated AY.2, but is not seen in India yet, the statement said.
"All Delta sub-lineages are treated as a variant of concern VOC, although properties of AY.1 are still being investigated. Currently, the variant frequency of AY.1 is low in India. Cases with AY.1 have been mostly reported from nine countries of Europe, Asia and America," the ministry statement stated.
The SARS-CoV-2 virus causing COVID-19 disease is mutating continuously with increase in the number of infections both across the world and in India.
Mutations help the virus to become either more transmissible or more virulent or both. With time these mutations known as Variants of Interest (VOI) increase in frequency in the selected population and are considered then as VOC.
Vaccine drive faltering
On Monday, India vaccinated a record 8.6 million people as it began offering free shots to all adults, but experts doubted it could maintain that pace.
"This is clearly not sustainable," Chandrakant Lahariya, an expert in public policy and health systems, told Reuters.
"With such one-day drives, many states have consumed most of their current vaccine stocks, which will affect the vaccination in days to follow."
With the currently projected vaccine supply for the next few months, the maximum daily achievable rate is 4 to 5 million doses, Lahariya added.
The effort has so far covered about 5.5% of the 950 million people eligible, even though India is the world's largest vaccine producer.
A devastating second wave during April and May overwhelmed health services, killing hundreds of thousands. Images of funeral pyres blazing in car parks raised questions over the chaotic vaccine rollout. Since May, vaccinations have averaged fewer than 3 million doses a day, far less than the 10 million health officials say are crucial to protect the millions vulnerable to new surges.
Particularly in the countryside, where two-thirds of a population of 1.4 billion lives and the healthcare system is often overstretched, the drive has faltered, experts say.
Maintaining the pace will prove challenging when it comes to injecting younger people in such areas, Delhi-based epidemiologist Rajib Dasgupta said.
The capital is also facing difficulties. Authorities in New Delhi said more than 8 million residents had yet to receive a first dose and inoculating all adults there would take more than a year at the current pace.
India has been administering AstraZeneca's vaccine, made locally by the Serum Institute of India, and a homegrown shot named Covaxin made by Bharat Biotech.
Last week, Serum Institute had said it planned to increase monthly production to around 100 million doses from July. Bharat now estimates it will make 23 million doses a month.
On Tuesday, television channel CNBC-TV18 reported that phase-3 data for Covaxin showed an efficacy of 77.8%.
India may also soon have a mass rollout of Russia's Sputnik V vaccine, and the government expects to import vaccines this year from major makers such as Pfizer.
Although new infections in India have dropped to their lowest in more than three months, experts say vaccinations should be stepped up because of the transmissibility of new variants.
Over the past 24 hours India reported 42,640 new infections, the lowest since March 23, and 1,167 deaths.
Infections now stand at 29.98 million, with a death toll of 389,302, health ministry data showed.
(With inputs from Reuters and PTI.)