Surge testing has begun in five postcode areas near Bristol after two confirmed cases of a new coronavirus variant first found in Brazil.
Public health bosses say the risk is "low" and "contained".
Drive-in surge testing sites are up and running with an extra three drop-off centres for home testing kits set to open on Tuesday 2 March.
The two cases of the Brazilian variant of Covid-19 in South Gloucestershire are from one household.
The cases originate from an individual who travelled back from Brazil on 10 February - five days before the quarantine hotel policy was introduced.
The traveller isolated in South Gloucestershire with the rest of their household under the rules in place at the time. One member was tested after showing Covid symptoms.
South Gloucestershire Council's public health director Sara Blackmore said: "This is a low risk situation, this is a contained situation and the risk to the community is low."
She told ITV News West Country the council is aware it could be more transmissible and less receptive of the vaccine, but there is no clear data on that yet.
She added the issue is "very contained", and said: "That said, we're very keen to respond and ensure we are keeping our community safe by putting in a belt and braces precautionary approach and additional testing in this area."
Watch Sara Blackmore's interview with ITV News West Country
Who should get a test?
Surge testing is being rolled out for people over the age of 16 who do not have symptoms living in five postcode areas on the outskirt of Bristol.
People who need to travel into these areas for work or visit their support bubble are also eligible for testing.
The affected postcodes
Drive-in test centres open now
Stoke Gifford Parkway Park & Ride
The Mall Coach Park at The Mall Cribbs Causeway from 9am
Surge testing sites now open
Patchway Community Centre, Rodway Rd, Patchway, Bristol BS34 5PF
Little Stoke Community Centre, Little Stoke Lane, Little Stoke, BS34 6HR
The Bradley Stoke Jubilee Centre, Savages Wood Road, Bradley Stoke, BS32 8HL (not available on Friday, 5 March).
Baileys Court Activity Centre, Bailey Court Road, Bradley Stoke BS32 8BH
Coniston Community Centre, The Parade, Coniston Rd, Patchway BS34 5LP
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