Professor Philip Nolan:

There is no point in testing where there is not some advance signal that the disease is present. There is both active testing, in other words, people who come forward because they are symptomatic, and proactive testing, that is, tracking down the contacts of those people and being proactive in terms of screening in areas where we think there is a risk of disease or a risk of major consequences if the disease breaks out. Even though it may reassure people, it is pointless and a waste of resources to start using the testing capacity in some broad-brush sense. Testing capacity ramps up as disease ramps up and ramps down, quite frankly, as disease ramps down.