Seeking to track the progress of the coronavirus across the UK, the Imperial College in London will carry out a major testing program to get a better estimate of the number of people currently infected with the virus.

The number of confirmed cases of COVID-19 in the UK has so far exceeded 165,000, with 26,097 deaths registered. The government has a target of 100,000 tests per day, but it’s so far falling short – with only 52,000 tests performed yesterday.

The program will be led by a group of scientists, researchers, and clinicians at the Imperial College and was commissioned by the Department of Health and Social Care. Testing is essential to eventually lift the lockdown, as it would give authorities a better picture of the number of people with the disease.

“Short of a vaccine, testing is the only way out of lockdown. But the testing landscape is like the Wild West with no rules, no standards and widely varying reliability. Even the most accurate test is useless unless it is usable,” said professor Ara Darzi, sponsor of the program at Imperial.

In the first part of the program, 100,000 randomly selected people from 315 local authorities across the UK will be invited to provide nose and throat swabs, which will be tested for antigens. This kind of test looks for evidence whether someone is currently infected with the coronavirus or not.

Then, in the second part, a number of different antibody tests will be assessed for their accuracy and how easily people can use them at home without assistance from a healthcare professional. Antibody testing is used to assess how far the infection has spread and what proportion of the population has been infected. A group of 300 people will also be given a sample test to self-administer, which requires them to place a finger prick of blood onto a testing kit and read the result. Researchers will then assess its acceptability and whether people understand the guidance on how to use it.

“Community testing is a vital next step in ongoing efforts to mitigate the pandemic, but to be successful this must be based on robust scientific evidence. Through this important program we will gather the critical knowledge base necessary to underpin community testing programs,” said Professor Paul Elliot.

If successful, the test will then be distributed to a larger group of up to 10,000 people. The aim is solely to ensure that people can properly self-administer the test, rather than to provide an accurate assessment of antibody levels.

A further stage will involve up to 5,000 key workers, who will both self-test and have the test administered by a health professional. These results will also be compared with gold-standard laboratory testing on participants’ blood samples. This will provide more information about the accuracy of the tests.

If antibody self-testing is found to work with a high degree of accuracy, acceptability, and usability, it will be rolled out to 100,000 people later this year, to provide an indication of the prevalence of Covid-19 based on natural antibodies in individuals’ blood.

Nevertheless, while the antibody tests could be helpful, their actual usefulness depends on the supposition that those who have had the virus are immune to new infections, an argument that is still an open question.

“As part of this project we will work with public volunteers and patient advisors to see how easy it is for people to do these tests at home, and co-design the information and packaging that will go out with the tests. We have already had an excellent response,” said Professor Helen Ward.