Two thousand households in parts of central and north Swindon will be written to this week urging them not to socialise with others as much as they have been doing.

It came after the town was placed on a government list of areas of particular concern on Friday. More than 50 people have tested positive for coronavirus since then.

Swindon Borough Council’s director of public health Steve Maddern said the bulk of new cases were in the SN1 and SN2 postcode areas, which covers the town centre, Old Town, Rodbourne, Gorse Hill, Ferndale, Pinehurst, Penhill and Upper Stratton.

But the health chief sought to reassure people the town was “nowhere near lockdown measures” and stressed that there was not an outbreak in SN1 and SN2 – just that the majority of the cases were connected to those areas.

The council would be writing to around 2,000 households this week urging them to follow government guidelines around social distancing, handwashing and wearing masks. People would also be asked to limit their social interactions with other households, as health officials fear this could be helping to drive the increase in cases. The letters will be in English only and will not be translated.

Mr Maddern told reporters on Monday evening: “This isn’t local restriction, this is just providing enhanced communication within those communities.”

He added: “I think it’s a cause for concern within those areas because we’re seeing the cases rising.

“But when we’re talking about things like restrictive measures and local lockdown, that is when we are seeing broader community transmission and in this situation we’re still not seeing that more broadly across the borough. It’s very much fixed in the SN1 and SN2 postcodes.

“I still don’t feel a local lockdown is imminent. I think what individuals and residents in those postcodes need to be mindful of – as do all Swindon residents – is it’s not a time for complacency. It’s not a time to be letting your guard down in regard to social distancing, hand washing and mask wearing.”

He said it was out of his hands and up to Whitehall whether a local lockdown was imposed. It was not possible for the council to place particular wards or postcode areas on lockdown.

As of 9am this morning, 1,029 have tested positive for coronavirus in Swindon – an increase of 55 since Friday morning. The majority of those who have recently tested positive have not shown any covid symptoms, including some of those tested following the “mini-outbreak” at XPO Logistics’ Iceland distribution plant.

Mr Maddern said 85 per cent of people suspected of having had contact with someone with coronavirus had been contacted by the NHS’s track and trace system. The council was looking to use dedicated teams of “tracers” – pledged by the government – to help track down the remaining 15 per cent.