What is contact tracing and how could it be used to lift the UK's coronavirus lockdown?

With the UK still in lockdown, Matt Hancock has announced plans to introduce contract tracing on a “large scale” as a way of easing coronavirus restrictions.

Speaking to MPs in the House of Commons on Wednesday, the health secretary said the UK had "reached the peak" of its COVID-19 outbreak.

Preparations on how to exit lockdown come as hospital deaths from coronavirus in England increased to 16,786 on Thursday, an increase of 514 on Wednesday’s figures.

What is contact tracing?

Anyone who has tested positive for COVID-19 will be interviewed in an attempt to discover who they have recently come into contact with.

Armed with this information, the interviewers will then speak to those people who may have been exposed to coronavirus, encouraging them to get tested themselves or to self-isolate as a precaution.

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In the UK, an NHS app is currently being developed that could identify people who have been in proximity to a smartphone user who subsequently developed coronavirus symptoms and tell them to self-isolate by using bluetooth technology.

What does it mean for me?

Targeting specific people who may have come into contact with people who have had coronavirus would potentially allow more targeted quarantine measures than the current blanket lockdown.

This could mean that strict lockdown measures could be relaxed as those who are infected, or at a possible risk of having been infected, are in quarantine.

Those who are not infected, or who have not been in contact with anyone who is, would arguably be able to go back to their daily lives. As a result, more shops and business could re-open, while new cases of COVID-19 could remain relatively small until a vaccine is found.

Is it effective?

The World Health Organization (WHO) recommends contact tracing as a strategy in controlling disease outbreaks. They highlight how it has been used to effectively control Ebola virus outbreaks in Africa.

Contact tracing has also been used in South Korea – where deaths from coronavirus have dropped sharply.

The country has a large team of contact tracers – in the region of 1,000 people – that were able to stop the spread of the outbreak, thereby avoiding lockdown measures. South Korea has had 240 deaths from coronavirus out of 10,702 cases, according to Johns Hopkins University. Their levels of new cases have remained low and stable since early March.

Why now?

The UK government abandoned community testing and contact tracing as a strategy to deal with coronavirus in March, after the number of cases and deaths began to rise. Boris Johnson said the the epidemic could no longer be contained by contact tracing and the country went into lockdown not long after.

However, with the UK now over four weeks into lockdown, and with figures showing the outbreak in the UK is one of the worst in Europe, the government has changed course.

Health secretary Matt Hancock told the health select committee that the government was about to start rebuilding contact tracing teams.

Public Health England had 290 contact tracers at its peak but Hancock confirmed that the figure would rise, and would work in conjunction with the app.

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