Surge testing and mobile vaccine units are being used in Bolton, the UK's hotspot of the Indian variant, ITV News Science Editor Tom Clarke reports
It was declared a "variant of concern" by Public Health England (PHE) last week as clusters of the new strain were be detected in some areas of the UK.
Here's everything you need to know about the Indian variant:
What do we know about the Indian variant?
The variant B16172, also known as VOC-21APR-02, was first detected in India in March.
It is one of three related variants of the virus. The other two variants - called B16171 and B16173 remain classified as "variant under investigation".
Is the variant responsible for the second wave in India?
India is in the midst of a crisis as a second wave of the virus has caused more than a quarter of a million deaths.
However, it remains unclear whether the new coronavirus variants are driving the second wave.
Experts say large gatherings, and lack of preventive measures such as mask-wearing or social distancing, have played a key role in the spread of the virus.
Although India has the world’s biggest vaccine-making capacity, the country has partially or fully immunised fewer than 10% of its 1.35 billion people.
Why has B16172 been designated as a variant of concern?
Scientists believe this variant can spread more quickly and is thought to be at least as transmissible as the variant detected in Kent last year, known as B117, which is the dominant strain in the UK.
Dr Susan Hopkins, Covid-19 strategic response director at PHE, said: "We are monitoring all of these variants extremely closely and have taken the decision to classify this as a variant of concern because the indications are that this VOC-21APR-02 is a more transmissible variant."
Is the strain more dangerous?
PHE said there is currently "insufficient evidence" to indicate that any of the Indian variants cause more severe disease.
However, there is evidence that the variant may infect younger people, according to data collected by India's Union ministry of health.
People under 45 accounted for 60% of all infections in the country but the disease is disproportionately fatal for those who are older.
Deaths in under-45s constituted 12% of deaths while 88% of fatalities in India were in people aged over 45, 55% were over 60.
Deaths in people aged between 18 and 25 years old as well as children under 17 accounted for only 1% of fatalities.
The data also showed that men are a lot more likely to be infected as well as die from the disease, accounting for 63% of all cases and 70% of all deaths.
Will the vaccine protect against it?
At present, there is no evidence this variant is resistant to current vaccines.
Although deemed to be more transmissible, it does not feature the E484K mutation found in the South African variant of the virus, which could help the virus evade a person’s immune system and may affect how well coronavirus vaccines work.
On Wednesday, the European Medicines Agency said it was "pretty confident" that vaccines currently in use will be effective against the Indian variant – a view echoed by some British scientists.
Vaccines could be used 'as a sword' to try and cut Covid transmission, says Tom Clarke
But Professor James Naismith told BBC Radio 4’s Today programme that not enough was known to say for sure whether the variant could frustrate the UK’s vaccination programme.
"The vaccines don’t 100% prevent infection for people," Dr Naismith said. "What they do, is they almost 100% prevent hospitalisation and serious illness."
He added: "We don’t know enough to know yet whether the Indian strain will behave differently than that.
"So even the regular virus can infect people who have been vaccinated and sometimes you do get reinfection. And the very, very large number of cases in India mean things that are rare will be detected."
Watch ITV News Science Editor Tom Clarke explain what we know about the Indian variant:
Where has it been detected in the UK?
According to data by PHE released last Friday, cases of the new variant doubled in the UK up to May 5 with confirmed cases at 520 compared to 202 in the previous week.
The report also showed 261 cases of B16171 and nine cases of B16173.
The cases are spread across England, with the majority in two areas – the North West, mainly in Bolton, and London.
PHE said around half of these cases are related to travel or contact with a traveller.
Surge testing has been under way in parts of Bolton since May 7, after PHE confirmed the town is one of the main locations for cases of the variant in England.
Greater Manchester Mayor Andy Burnham has submitted a request to the Joint Committee on Vaccination and Immunisation (JCVI) that all over-16s in Bolton, along with the rest of the Greater Manchester area, are able to receive a Covid-19 vaccination "to mitigate the risks of spread in those communities where we are seeing more transmission".
Health protection teams are working with local authorities, public health officials and NHS Test and Trace to detect cases and limit onward spread.
But experts warn that the variant will spread widely across the country.
Dr Deepti Gurdasani, a clinical epidemiologist and senior lecturer at Queen Mary University of London, told The Guardian that "at the current doubling rate [it] could easily become dominant in London by the end of May or early June".
Prof Naismith said the variant may spread "way beyond" the areas where it has been detected.
"I think we should view it as a country-wide problem," he said. "It will get everywhere. We keep learning this lesson, but we know that this will be the case."
What other variants of concern have been identified in the UK?
All viruses undergo small genetic changes as they make copies of themselves in the host.
Most of these mutations are harmless but some can make the disease more infectious or threatening, and evade protection gained through infection or vaccination.
Both the South Africa variant (B1351) and the Brazil variant (P1) have been detected in the UK.
Imperial College London’s React programme looked at variants of coronavirus and found that of 115 positive swabs, 24 cases were identified as the Kent variant and two of three cases in London were identified as the Indian variant of concern.
The experts said neither participant had been abroad in the previous two weeks.
Current vaccines have been designed for earlier versions of coronavirus, but scientists believe they should still work, but may be less effective.
But experts are confident existing vaccines can be tweaked to better tackle emerging mutations.
The UK Government has a deal with biopharmaceutical company CureVac to develop vaccines against future variants, and has pre-ordered 50 million doses.
What does this mean for the roadmap out of lockdown?
The Scientific Advisory Group for Emergencies (Sage) is reportedly due to hold an emergency meeting on Thursday to discuss the spread of the Indian variant, amid fears it could have an impact on the Government’s roadmap out of lockdown.
When asked if the India variant could delay the June 21 relaxation of coronavirus restrictions, Foreign Office minister James Cleverly said the decision will be "driven by the data".
Mr Cleverly said: "The Prime Minister said right from the start that the decisions that we make about the roadmap and the timing of changes will be driven by the data and by the scientific evidence.
"It wouldn't be right or appropriate for me to speculate as to what decisions might be made."
He added: "We have always said that whilst we have seen the figures improve very significantly, in a large part because of the vaccine roll-out, we are not out of the woods yet.
"We do all still need to be careful and we will be making decisions based on the analysis of this and other variants in due course."
Health Secretary Matt Hancock has said the emergence of new coronavirus variants represent the “biggest risk” to lockdown easing in England.
Mr Hancock told BBC Breakfast: "There is no doubt that a new variant is the biggest risk. We have this variant that was first seen in India - the so-called Indian variant - we have seen that grow.
"We are putting a lot of resources into tackling it to make sure everybody who gets that particular variant gets extra support and intervention to make sure that it isn’t passed on.
"However, there is also, thankfully, no evidence that the vaccine doesn’t work against it."