A new surge of coronavirus infections have caused devastation in India, triggered largely by a contagious new variant. As it spreads, concerns are mounting about the ramifications for the rest of the world, including New Zealand.
Cases of the so-called "Indian variant" were detected from travellers from India in MIQ facilities in April, which led to Prime Minister Jacinda Ardern putting a travel ban from India into New Zealand.
What is the Indian variant?
There are at least three closely related variants which originated in India: B.1.617, B.1.617.2, and B.1.617.3.
They have been blamed for India's recent catastrophic second surge of infections – the country accounted for 50 per cent of all cases reported worldwide last week and 30 per cent of deaths – although there are almost certainly other factors at play.
According to the World Health Organisation (WHO), B.1.617 and B.1.617.2 appear to be highly contagious; so far they have been detected in 34 and 31 countries respectively. It is thought B.1.617.3 will follow the same trend, but there's not yet enough evidence to confirm suspicions as it emerged more recently.
However, it is B.1.617.2 that is currently on the march, spreading most rapidly in India and across Britain.
What distinguishes the Indian variants from others?
The B.1.617.2 has a mutation on the spike protein – which the coronavirus uses to latch onto human cells – called L452R. This was also detected in a variant spreading in California earlier this year and is thought to explain why the variant spreads more easily.
Unlike the other variants in the B.1.617 family, though, it does not have the E484Q mutation. This mutation resembles another known as "Eek", or E484K, which may help the virus evade some types of antibodies.
The presence of these two mutations, among many others, are why the Indian variant family was dubbed a "double mutant" – an essentially meaningless, but headline-grabbing, term.
Have they arrived in Britain?
Yes, cases of all three have been found in Britain. B.1.617.2 was formally designated a "Variant of Concern" by both the WHO and Public Health England (PHE) – the latter agency did so because there is "strong evidence" that the variant has a transmission advantage.
According to analysis by the Telegraph, it has spread three times faster than previous imported variants of concern, such as that from South Africa.
The two other Indian variants remain "under investigation".
Where in Britain is it?
Across the four nations, England has reported the bulk of cases – 1255 of B.1.617.2, compared to 35 in Scotland, 11 in Wales and 12 in Northern Ireland, as of Thursday 13 May.
The hotspots are predominantly located in the North West and London, but health officials in Bedford have also raised alarm at an apparent spike. In Blackburn and Bolton, the B.1.617.2 variant is thought to have driven a doubling of infections over the past seven days.
Across the UK, 368 cases of B.1.617 and 11 cases of B.1.617.3 have also been detected.
How much more transmissible is it?
B.1.617.2 was formally designated a "Variant of Concern" by Public Health England (PHE) because there is "strong evidence" the variant has a transmission advantage.
On Friday, Prof Chris Whitty, England's Chief Medical Officer, confirmed the Government's Sage advisory group had "confidence" the variant was more transmissible than the Kent variant.
According to papers published by Sage, "it is a realistic possibility that this new variant of concern could be 50 per cent more transmissible".
The paper adds that, if this is the case, "it is a realistic possibility that progressing with all Roadmap steps would lead to a substantial resurgence of hospitalisations".
Do vaccines work against it?
We think so. In India, where most health workers were vaccinated early, there have been very few hospitalisations and deaths among this cohort.
In the UK, too, early signs in Bolton and Blackburn look positive – there are far fewer cases in those over 60 who have been vaccinated compared to those in younger age groups.
Recent studies on the other variants, which are similar, also hold promising signs.
Prof Danny Altmann, an immunologist at Imperial College who was involved in one of the studies, said the Indian variant currently looked like "less of a problem" for immune evasion than the Brazilian or South African variants.
And he stressed the current vaccines continue to provide "good enough" protection against all the existing variants of concern.
Does it cause more severe disease?
In the UK, as the majority of cases are very recent, PHE says there has been "insufficient follow up time to allow an assessment of severity".
There have been four deaths among the 1255 cases detected in England to date, which took place between May 5 and May 12.
But this does not suggest the variant is more deadly: a more contagious strain means more infections and more serious cases, which leads to more Covid-19 deaths.
Can you catch it if you have already had coronavirus?
It's not completely clear, but there are positive signs that the answer is no.
An ongoing study of healthcare workers nationally has suggested there is no signal of an increase in reinfections, according to PHE, and as it stands possible reinfections detected nationally "appear approximately proportionate to the prevalence of this variant".
But a small lab study has suggested B.1.617.2 can more commonly evade antibodies triggered by early Covid strains compared to the Kent variant, or B.1.1.7. It is less likely to cause a reinfection than the South Africa variant, B.1.351.
PHE stresses that this research requires corroboration.
If vaccines work against it why are people worried?
Because more than 40 per cent of the country has not been vaccinated yet and only 30 per cent has had both jabs - although the hope is that the oldest and most vulnerable are protected because they were vaccinated first.
Experts worry if it starts circulating widely it could lead to another big spike in hospitalisations and deaths.
Modelling this week from the University of Warwick, which considered what might happen if a new variant of the virus got a grip, warned: "England remains extremely vulnerable to novel variants.
"A variant that is 30-40 per cent more transmissible than B.1.1.7 [Kent] is projected to generate more total hospital admissions than the first wave. Variants that escape immunity (either from infection or vaccination) could generate outbreaks larger than the second wave."
How fast is the Indian variant spreading?
Recorded cases have more than doubled for the second consecutive week, and if you look at a graph of the variant's growth, it looks scary. But it is rising from a very low base. The absolute number of recorded cases is just 1,313 – there is still time for it to be stopped.
What is the government doing to contain it?
As of Friday, May 14, the Government has announced there will be surge testing in 15 areas. The army, led by Colonel Russel Miller – the commander of the north west region – will be deployed to support local leaders in managing the response to the Indian variant on the ground.
This will include surge testing, mobile testing units and the army will be on the streets handing out tests.
UK's Prime Minister Boris Johnson also said at a Downing Street press conference there would be "targeted new activity" in Bolton and Blackburn to accelerate the vaccine take-up, including longer opening hours at vaccination sites.
But Whitty stressed that vaccinating everyone over 18 early would have implications for vaccine supply for other areas - and warned it also takes a good few weeks for vaccine protection to kick in fully.
How does it impact the UK?
Johnson has ruled out delaying the easing of lockdown on May 17, when people will be able to mingle inside in groups of six or with two households, and pubs, restaurants and museums can reopen indoors.
But Johnson has left the door open to localised restrictions, though these proved problematic when introduced last year, and warned that the fourth stage of reopening may be delayed on June 21.
"I have to level with you, that this new variant could pose a serious disruption to our progress, and could make it more difficult to move to step four, in June," he told a press conference. "I urge everyone to exercise the greatest caution, because the choices we make in the coming days will have a material effect on the road ahead."
How does England's approach compare to Scotland?
Scotland has taken a slightly different strategy. A coronavirus hotspot has been detected Moray and Glasgow, the devolved Government is accelerating the vaccine rollout to residents aged between 18 and 39.
The two areas will also remain under level three coronavirus restrictions while the rest of the mainland moves to level two on Monday, in an attempt to curb the spread of the variant.
Are there other variants of concern?
Yes, PHE has so far identified five. These include the South African variant, B.1.351, and P.1, which was first found in Brazil. Cases caused by these variants in the UK are also growing in number, but at a much slower rate – 81 and 19 new cases, respectively, were reported on Thursday.
The Kent variant, B.1.1.7 – which is now dominant in the UK and much of Europe – is also a variant of concern, as is a variation also in this family, known as B.1.1.7 with E484K.
How concerned should we be about the Indian variant and other variants?
The best-case is that infections stay under control thanks to the UK's speedy vaccine roll-out, and the variant has, ultimately, little impact.
But the more worrying scenario is that the new variant takes hold among the communities with low vaccine uptake, where it could cause a major rise in cases and, subsequently, deaths.
This is a fear globally, too: the nightmare scenario is that the new variant takes hold in countries which have been unable to access vaccinations, driving severe new waves.
What is our best line of defence?
Get vaccinated and encourage everyone you know to do the same.