2020欧洲杯体育足彩外围app

How does the NHS contact tracing app work? An easy eight-step visual guide

The app is being tested in the Isle of Wight
The app is being tested in the Isle of Wight Credit: PA

The NHS contact tracing app will be trialled in the Isle of Wight this week.

The app, which can identify with whom a person infected with coronavirus2020欧洲杯体育足彩外围app has been in contact, has been billed as a key to easing social distancing measures, helping to pinpoint those who need to be in quarantine.

Here's how it works: 

Download app
2020欧洲杯体育足彩外围app The NHS Covid-19 app is downloaded from Apple or Google app stores and then users enable it to use Bluetooth feature on their smartphone.

Provide postcode
When setting up the app, users will be asked to enter the first half of their postcode. This is so the NHS can use the data to see where hotspots of infection are breaking out. Users are not asked for any more details until they want to report symptoms.

Keep the phone with you
The app will run in the background of the phone, periodically waking up when it sense another phone with the app coming into range. It will then use Bluetooth to measure how far away the other person is every 15 seconds. The app will log the other phone for 28 days if the two devices came into close contact.

Report symptoms
2020欧洲杯体育足彩外围app If a user develops flu-like symptoms, they report these in the app. They will be asked a series of clinical questions. This will be similar to other NHS reporting functions, such as the 111 services.

Data are analysed
The answers will then be analysed by the NHS’s artificial intelligence (AI) programme. If the AI decides the symptoms meet a threshold for Covid-19, that person should self-isolate for 14 days.

Alert sent to previous contacts
The AI will then analyse contacts the symptomatic person has logged in the app to decide the potential risk of infection for each. People deemed to have had ‘high risk’ contact with someone reporting Covid-19 symptoms will then be sent an alert advising that they self-isolate for 14 days.

Sufferer is tested
When a user reports symptoms that are suspected to be Covid-19, they will be directed to where they can arrange an NHS viral swab test. In the Isle of Wight trial starting this week, this will be via a call centre. But NHS developers hope this will be arranged in the app by the time it rolls out to the rest of the country.

Test results
If the test is positive self-isolation advice remains in place for all alerted. A PHE contact-tracing team will follow up with the tested user and find other people they may have infected. If the test comes back negative, the app will send out a second alert to the contacted people telling that they can stop self-isolating.

Read more: Contact tracing: what is the UK's test, track and trace plan?