Ministers today admitted they are still searching for the unidentified sixth case of the Brazilian coronavirus variant in the UK as it emerged the strain has been identified in at least 15 countries not on the travel 'red list'.
Business Secretary Kwasi Kwarteng this morning confirmed the person is yet to be found as he said 'we are still trying to work out exactly what has happened to that potential carrier'.
Mr Kwarteng said the Government is 'still monitoring the situation very closely' as it scrambles to stop the variant from spreading.
The strain, first discovered in the Brazilian city of Manaus, has spooked experts and ministers because it has mutations which are thought to increase transmissibility.
There are also concerns that the variant can re-infect people who have previously had Covid and that it has the ability to lessen the impact of vaccines.
The Government has deployed surge testing in South Gloucestershire after two cases of the variant were identified there
WHAT DO WE KNOW ABOUT THE BRAZIL VARIANT?
Date: Discovered in Tokyo, Japan, in four travellers arriving from Manaus, Brazil, on January 2.
Why should we care? The variant has the same spike protein mutation as the highly transmissible versions found in Kent and South Africa - named N501Y - which makes the spike better able to bind to receptors inside the body.
It has a third, less well-studied mutation called K417T, and the ramifications of this are still being researched.
What do the mutations do?
The N501Y mutation makes the spike protein better at binding to receptors in people's bodies and therefore makes the virus more infectious.
Exactly how much more infectious it is remains to be seen, but scientists estimate the similar-looking variant in the UK is around 56 per cent more transmissible than its predecessor.
Even if the virus doesn't appear to be more dangerous, its ability to spread faster and cause more infections will inevitably lead to a higher death rate.
Another key mutation in the variant, named E484K, is also on the spike protein and is present in the South African variant.
E484K may be associated with an ability to evade parts of the immune system called antibodies, researchers from the Federal University of Rio de Janeiro said in a scientific paper published online.
However, there are multiple immune cells and substances involved in the destruction of coronavirus when it gets into the body so this may not translate to a difference in how people get infected or recover.
Do our vaccines work against it?
There are concerns that vaccines might be less effective against the Brazilian strain, with trials of the Johnson & Johnson jab finding it was slightly less effective in Latin America at preventing mild or moderate cases.
However, the trials found it still prevented hospitalisations and deaths.
No studies have tested the Oxford/AstraZeneca vaccine against the P1 variant, while Moderna and Pfizer say their mRNA coronavirus vaccines should work against variants with the E484K mutation, with early results showing that these vaccines are only slightly less effective against the P1 variant.
The discovery of the six cases in the UK has prompted criticism of the Government's hotel quarantine policy, with Labour arguing it is not strict enough.
Calls for the system to be toughened up are likely to grow after it emerged the concerning strain has been identified in at least 15 countries not on the 'red list'.
The Guardian reported that a list of verified cases compiled by the World Health Organisation includes the US, Canada, France, Germany, Spain and Japan.
The Government's 'red list' policy in England currently bans travel from more than 30 countries which have had variant outbreaks.
UK citizens can still come back from those countries but they must spend 10 days in a quarantine hotel.
Travellers returning from non-'red list' countries must self-isolate for 10 days at home.
Labour has repeatedly called for the policy to be strengthened, arguing the Government's border measures are always 'too little, too late'.
Health Secretary Matt Hancock last night defended the border arrangements as he argued that home quarantine measures were already in place and travel restrictions on Brazil had been imposed before the hotel policy was implemented.
Mr Kwarteng was asked during an appearance on Sky News whether the sixth case had been found.
He replied: 'I think we are still monitoring the situation very closely and you are quite right, I think there was one case of the Brazilian variant, as far as I know there are six cases, but there is one where the person involved didn't fill in the forms correctly and we are still trying to work out exactly what has happened to that potential carrier.
'But we are dealing with this situation and I would like to remind you also that we have the South African variant and we have been dealing with that too.'
The missing person is thought to have been tested on February 12 or 13, possibly via a home postal test or a test collected from a local authority.
In total, Public Health England has identified six UK cases of the concerning so-called P1 variant – three in England and three in Scotland.
Three cases are Scottish residents who flew to Aberdeen from Brazil via Paris and London, who all tested positive while self-isolating.
Other passengers who were on the same flight to Aberdeen are now being traced.
The other two cases in England are from the same household in South Gloucestershire after one person returned from Brazil on February 10 – just days before the Government's hotel quarantine rule came into force.
Two other people in the same household have also tested positive but are not currently included in the UK case total of six, while tests on their type of coronavirus continue.
Officials are searching for passengers who were on the Swiss Air flight LX318 from Sao Paulo to Heathrow, via Zurich, which landed on February 10.
Surge testing will now be carried out in the Bradley Stoke, Patchway and Little Stoke areas of South Gloucestershire to capture any potential spread in cases.
Labour leader Sir Keir Starmer said the discovery of the variant in the UK showed the Government had not 'secured our borders in the way we should have done'.
Vaccines minister Nadhim Zahawi said any community transmission of the variant would be identified 'very, very quickly' through both regular PCR and lateral flow testing.