Video report by ITV News Correspondent David Wood
Targeted Covid testing has been extended to more postcodes in England after variants of the virus were discovered in those areas.
People living in Worcestershire WR3 postcode, the PR9 postcode in Sefton, Merseyside, and within areas in Bristol and South Gloucestershire are being "strongly encouraged" to get tested in a bid to stop the spread of new coronavirus variants.
Last week the health secretary warned tens of thousands of people in a list of areas to take "extra special precaution" in order to avoid spreading the South African coronavirus variant.
A door-to-door testing blitz of 80,000 people promptly got underway in the listed areas.
On Saturday, the Department for Health and Social Care said more areas will now have additional testing made available.
A statement said: "Working in partnership with local authorities, additional surge testing and sequencing is being deployed to targeted areas around Worcestershire WR3, an area in Sefton PR9, and areas in Bristol and South Gloucestershire, where Covid-19 variants have been found."
Check if your postcode is in one of the targeted areas:
Last week the government announced targeted testing in the following areas:
East of England (EN10)
London (W7, N17, CR4)
North West (PR9)
South East (GU21 - testing in ME15, which began on Monday, is now complete)
West Midlands (WS2)
On Saturday, the list of areas was extended to include:
Areas in Bristol and South Gloucestershire
The DHSC said people living in those areas were being "strong encouraged" to get tested, regardless of whether they had symptoms or not.
"Positive cases will be sequenced for genomic data to help understand Covid-19 variants and their spread within these areas," the statement added.
The development comes amid reports the Oxford/AstraZeneca vaccine might not be as effective at preventing mild illness among people who have the South African variant.
The Financial Times reported the findings of a report set to be published on Monday.
David Wood has more on the findings of the preliminary study:
The findings were, however, the result of early studies involving a very small number of people.
AstraZeneca told ITV News: "We do believe our vaccine could protect against severe disease, as neutralising antibody activity is equivalent to that of other Covid-19 vaccines that have demonstrated activity against more severe disease, particularly when the dosing interval is optimised to 8-12 weeks.
"Oxford University and AstraZeneca have started adapting the vaccine against this variant and will advance rapidly through clinical development so that it is ready for Autumn delivery should it be needed."
In a briefing last week, Matt Hancock warned 105 cases of the fast-spreading variant had been identified in the UK - 11 of which have no link to international travel, suggesting the strain had been passed on through community transmission.
There is no evidence to suggest the new variant is more deadly compared to the original strain, but it is believed to be more infectious.
The latest testing blitz comes amid reports pubs and restaurants may be allowed to reopen in April - so long as they do not serve alcohol.
Other options thought to be under consideration by the government include keeping pubs shut until May but allowing them to serve takeaway pints from April.
No official dates have been given over the easing of Covid-19 restrictions, with Boris Johnson previously saying England's lockdown will remain in place until at least March 8 when it is thought schools may be allowed to open.
Other reporters have suggested a longer school day is being considered by the government in a bid to help children catch up from the disruption caused by the pandemic.
The Daily Telegraph said that officials at the Department for Education (DfE) are considering multiple proposals to help children try and recover lost learning due to school closures.
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