From today, people who are double vaccinated against COVID-19, or are aged under 18, do not have to isolate for 10 days if they have contact with a positive case.

They are instead advised to take a PCR test, wear a face covering in enclosed spaces and limit contact with other people.

People who test positive or show symptoms are still legally required to self-isolate for 10 days.

Those without symptoms are still advised to take a lateral flow test twice a week, even if double-vaccinated, to help prevent the spread of infection.

The change in self-isolation rules in England and Northern Ireland comes as COVID-19 cases in Hertfordshire are on the rise. In the seven days to August 10 a total of 3,513 cases of coronavirus were recorded - a 5.9 per cent increase (195 cases) on the previous week - putting the county's case rate at 293.8 per 100,000 people.

Jim McManus, director of public health at Hertfordshire County Council, said: “I know the changes to the self-isolation rules will be welcomed by many residents and will be a huge relief to businesses that have been struggling with staff having to self-isolate. The virus is still circulating so it still means we have to take precautions like ventilation, being careful in crowds and wearing masks when asked to.

“I hope this will encourage more people who haven’t had their vaccinations yet to book an appointment or drop in to one of our vaccination centres. It’s quick and easy, will protect you and the people around you, and will mean you don’t have to self-isolate if you’ve been in contact with someone with COVID-19, or when you get back from a holiday in an amber list country.

“The most important thing right now is for us all to keep doing the things which stop infection. Get vaccinated if you are 18 or over, give people space, wear face coverings in crowded indoor areas, ventilate your workplaces and social spaces, get tested and self-isolate when required. These measures have kept us safe and will keep us safe still.”

To count as fully vaccinated, you must have both doses of the vaccine and wait for 14 days after your second dose. By law, people who are not fully vaccinated will still have to self-isolate for 10 days when told to by NHS Test and Trace or when returning from an amber list country.

To book a vaccination appointment, or find a walk-in clinic and opening times, visit covid.healthierfuture.org.uk

To find your nearest testing site or get a home test, visit hertfordshire.gov.uk/rapidtest