The React study 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.
Boris Johnson will hold a 5pm press conference today (Friday) after admitting he is "anxious" about a fast-spreading Indian variant amid a doubling in United Kingdom cases - up to 1,313 from 520 last week.
Latest figures show there are 1,313 cases of the variant in the United Kingdom, up from the 520 recorded the previous week.
"At the moment there is a very wide range of scientific opinion about what could happen".
Scientists are keeping a close eye on the spread of the variant across the United Kingdom, with a big rise in cases expected to be revealed on Thursday.
As set out in the roadmap, we can not rule out re-imposing economic and social restrictions at a local or regional level if evidence suggests they are necessary to contain or suppress a variant which escapes the vaccine.
"Obviously there's surge testing, there's surge tracing".
Wards with high infection rates are generally in more deprived areas often associated with more cramped living conditions, people in public-facing jobs and individuals with underlying health conditions.
On Thursday, Blackburn with Darwen Council initially said all over-18s would be offered a jab, before later stating only those with underlying conditions could book a vaccination.
The Department of Health and Social Care says "economic or social" restrictions could be imposed in parts of England, if any variant "escapes the vaccine".
"I am glad we are on a one way road to freedom, as the prime minister has stated, and freedom from COVID regulations, as the health secretary has undertaken to MPs in the House of Commons".
Indian COVID strain `variant of concern` but not vaccine resistant
Swaminathan further warned that chances of such unsafe variants emerging is more in the coming days. Over the weekend, Mkhize announced that two more Covid-19 variants had been detected in SA.
"We have always been clear we would be led by the data".
The Prime Minister's official spokesman told a Westminster briefing: "We want to consider all options".
Earlier, Professor Steven Riley, from Imperial College London, said whether the road map for England continued on its planned trajectory was "a Government decision" but suggested the United Kingdom was now in a good place.
They are believed to be largely household clusters linked to people who travelled from India.
On Wednesday, the European Medicines Agency said it was "pretty confident" that vaccines now in use would be effective against the Indian variant - a view echoed by some British scientists.
"We have decided just to pause, wait to see how significant the spread of the Indian variant is... not wanting to put at risk the very good position we are in in Wales today".
She said: "As foreign travel opens up more, we do really need people to follow that advice when they return from foreign countries in terms of the quarantining that they need to do".
Prof Naismith said the variant may spread "way beyond" the local areas where it has been detected, suggesting much wider community transmission of the variant.
Elsewhere, Professor Adam Finn, from the University of Bristol and a member of the Joint Committee on Vaccination and Immunisation (JCVI), suggested there was no firm plan for vaccinating teenagers and younger children.
Steve Baker, the deputy chair of the Covid Recovery Group of Tory backbenchers, said: "Why on Earth would we lock down when the vaccines continue to break the link between cases and hospitalisations and deaths?"
Prof Finn also said he is not "particularly concerned" that younger age groups may shun vaccines.