We've all done it: ignore a phone call when you don't recognise the number.

However, Cornwall Council has put out a warning today that in doing so it could be putting your own and other people's health at risk, if it is an NHS Test and Trace call.

The authority is urging people to answer their phone if the number starts 0300, as it could be warning that you've been in contact with someone who has tested positive for Covid-19.

It comes after new figures showed that around 40 per cent of people in Cornwall identified as being in this situation are currently not engaging with the Test and Trace team, potentially putting lives at risk.

The council said: "Increasing the number of people who take part in Test and Trace could reduce the chance of a second wave of Covid-19 in Cornwall significantly, by giving real-time data and the best information possible to stay on top of the situation.

"The council is already working closely with Public Health England to follow up cases identified by NHS Test and Trace, so that they can identify outbreaks as soon as possible."

Read next: Coronavirus in Cornwall round up – Thursday, August 6

The first type of contact by the NHS Test and Trace team will be by email, if possible, asking you to click on a link for further information and instructions.

If the team receives no response to the email, someone will then phone you and provide instructions about what you need to do. The calls will come from an 0300 number.

Anyone with symptoms of Covid-19 can either go online to order a test at www.nhs.uk/coronavirus or call 119, with mobile testing units located across the county.

If they are confirmed as a positive case they will be contacted by the NHS Test and Trace team and asked to give details of people they have been in close contact with over the last few days.

The NHS Test and Trace team then get in touch with those people and inform them they have been in close contact with a positive case and advise them what to do next.

Councillor Sally Hawken, Cornwall Council's portfolio holder for children, wellbeing and public health, said: “This is one of the ways we are all expected to play our part in limiting the spread of the virus.

"By not taking part people are potentially putting lives at risk in their community and increasing the risk of an outbreak of cases that could lead to parts of Cornwall, or even all of Cornwall, experiencing another lockdown.

"We know that there are many reasons people might not engage, but we’re safer together if we all do our part."

Rachel Wigglesworth, Cornwall Council’s interim director of public health, agreed: “Now lockdown is easing it could be that people are more relaxed and think there is less of a threat, or it could be that some people don’t answer their phones to numbers they don’t know, but it’s crucial that we all play our part to help limit the spread of the virus.

“Check your emails regularly, answer the phone and see who is calling. If it is the NHS Test and Trace service, then follow the instructions you are given.

"If you have symptoms then arrange a test as soon as possible and self-isolate.”