False Reassurance?

Politician, Lord Bethell, has stated that tests have "already demonstrated that lateral flow tests (for Covid-19) can be the reliable, highly sensitive technology we need". This is precisely the technology used in the Liverpool mass screening and intended for use in UK universities, before their students return home to their families for Christmas. He completely overstates the confidence we can have in such tests. Professor Sian Taylor-Phillips, provides a useful overview of the test's limitations, especially in relation to their proposed use in the university exercise (https://www.theguardian.com/commentisfree/2020/dec/01/uk-students-tests-coronavirus-testing-university-false-negative-results). She points out that the 30 minute test actually misses infections on between 25-50% of the occasions when it is used. It only records a positive value for patients with a 'good' viral load. This only occurs a few days after infection. As many as 20% of people with a Covid-19 infection are asymptomatic. Although the whole exercise is designed to identify asymptomatic students (who could infect vulnerable people in their home locations), the lateral flow test is specifically not designed, by its manufacturers, to be administered to such people. Taylor-Phillips states that the testing regime proposed for universities (2 tests, given a few days apart, with self-isolation over the entire period), will result in the lowest chance of students carrying the virus but cannot rule out infection. This will be the case, even if the 'rules' (especially the self-isolation phase) are strictly followed. There is a serious danger that many students and their families will assume, on the basis of the tests, that their return home is 'safe'. They will naturally want to meet up with elderly relatives and party with friends. Students need to be a bit more cautious and politicians need to be a bit more careful with their words.