Scientists say they have developed a Bluetooth tracing system which is ready to be deployed into an app in the fight against coronavirus.

A team at UCL (University College London) have been working on the technology with data privacy experts to ease concerns of misuse.

Contact tracing has been widely discussed as a potential solution to help end the Covid-19 lockdown, following in the footsteps of Singapore, where a similar offering has been adopted.

The idea is to use Bluetooth technology to keep a log of those who have been in close proximity to you, and send out an alert if any anonymously declare themselves as tested positive, with advice on further steps to take.

UCL’s system, known as DP-3T, has been devised in such a way that no personal data ever leaves an individual’s device, and is not centralised in a cloud server, meaning it cannot be used for anything other than public health.

They say the system hides all personal information from the server, using anonymous identifiers.

“There are a lot of concerns about Bluetooth tracing being administered centrally by governments, particularly in countries that have weaker privacy laws and concern for human rights,” said Dr Michael Veale, data rights and regulation lecturer at UCL.

“We have developed a practical solution that could help tell someone when they come into contact with someone that has tested positive for Covid-19, while at the same time ensuring that the user’s information never leaves their phone.”

The system is built in such a way that it prevents tracking of non-infected users and will dismantle itself at the end of the pandemic.

Scientists behind the project have released a white paper on its development, for public scrutiny, and have proposed it as one of the ideas for a pan-European mobile app to track the spread.

“Given this is a global problem, it is key such a system works across borders, so they can be re-opened,” Dr Veale continued.

“If one country uses a centralised system, then they all have to, putting citizens of countries with limited respect for human rights or the rule of law at serious risk.

“In our system, it works the other way, citizens around the world would be protected from surveillance and misuse, while epidemiologists get the insights they tell us they need.

“We have developed a decentralised privacy design to ensure individual data remains anonymous, we prevent abuse of data by third parties, and prevent tracking of non-infected individuals.

“There is really no good reason not to adopt such a private system, and if less private alternatives are deployed, it should raise serious questions about future plans.

“We are opposed to data being collected centrally, as this raises questions over future intended purposes of individual information, and will affect the adoption of any such app.

“If it is not adopted by over a majority of the population because users do not trust it to not misuse their data, the research indicates it will not be useful and this could endanger lives.”

NHSX, the national unit tasked with driving forward a digital transformation of the UK’s health and social care, has previously said it is “looking at whether app-based solutions might be helpful in tracking and managing coronavirus” and has “assembled expertise from inside and outside the organisation to do this as rapidly as possible”.