The Government has said it is “crucial” for people to quarantine after being “pinged” by the NHS Covid-19 app.

Its message comes just hours after a minister suggested that people should not automatically self-isolate if they are “pinged” by the app but should instead make an “informed decision”.

Their comments come amid concerns about the so-called “pingdemic” sweeping the country, with business chiefs warning of crippling staff shortages.

– What is this pingdemic then?

With case numbers rising sharply in England as restrictions are lifted, the country has seen what has been dubbed as a “pingdemic”, with hundreds of thousands of people told to stay at home after being deemed to have been in close contact with someone who has tested positive for Covid-19.

Latest figures showed more than 500,000 people in England and Wales were notified by the NHS Covid app to self-isolate – so-called being “pinged” – in the week up to July 1.

It means many small businesses are having to close completely, while even larger companies are affected – pub chain Greene King has shut 33 pubs in the last week, and PureGym said up to 25% of staff are isolating in some areas.

The pingdemic has led to calls from business owners to reform the current self-isolation rules.

– What are the current self-isolation rules?

NHS guidance says that people should self-isolate immediately if they have Covid-19 symptoms, test positive for the virus, live with someone with symptoms or has tested positive, or have been told to isolate by NHS Test and Trace or the NHS Covid-19 app.

People isolating should not go to school, work or public places, use public transport or taxis, go out for food or medicine, have visitors, or go out for exercise.

– So anyone pinged by the app has to isolate?

It is not as simple as that.

While there is a legal duty in England for people to self-isolate if they test positive or are contacted by NHS Test and Trace, this does not extend to the app.

So people who do not isolate after testing positive or being contacted by NHS Test and Trace can face fines of up to £10,000 – this does not apply to people being pinged.

The Government has said this is because users of the official NHS Covid-19 contact tracing app are anonymous and “we cannot force them to self-isolate or identify them if they are not self-isolating”.

Also, Prime Minister Boris Johnson has said that isolation rules will be relaxed for a “small number” of fully-vaccinated critical workers including health and care workers.

Mr Johnson also said it was necessary to keep the isolation rules largely unchanged until August 16, when a testing regime will replace the requirement for fully-vaccinated contacts to isolate.

– What have ministers said about being pinged?

Business minister Paul Scully said self-isolating after being told to by the app was a decision for individuals and employers.

Another minister in the business department, Lord Grimstone of Boscobel, stressed in a letter to one large employer that the app was only an “advisory tool” and that people were not under any “legal duty”, The Times reported.

– Is this official advice?

Apparently not.

Downing Street slapped down Mr Scully and said it was “crucial” to self-isolate when told and businesses should be supporting employees to do so.

Isolation remains the most important action people can take to stop the spread of the virus

A No 10 spokeswoman said: “Isolation remains the most important action people can take to stop the spread of the virus.

“Given the risk of having and spreading the virus when people have been in contact with someone with Covid, it is crucial people isolate when they are told to do so, either by NHS Test and Trace or by the NHS Covid app.”

– How does NHS Test and Trace work?

If you test positive for coronavirus, you will be contacted by contact tracers and asked to provide details of people you have been in close contact with and places you have visited.

In England, if you have come into contact with someone who has tested positive for Covid-19, you will be contacted and told to isolate for 10 days from your last contact with the person with Covid-19, even if you do not have symptoms.

– What about the app?

The app uses Bluetooth from your smartphone to keep a log of others who are also using the app whenever they are in close proximity to you.

To be considered a close contact, it generally means having been within two metres of someone for 15 minutes or more, such as on a bus journey.