Many tests are being developed in privately-run labs by independent firms. In the short-term, the goal should be for them to develop multiple, independent tests, that can then be mixed and matched to create a gold-standard approach. If a test is imprecise, it could give different results when administered twice in quick succession to a patient. In this case, repeating the same test twice can also improve accuracy.
A quite different smart testing tactic is to pool individual samples. With this approach, 20 blood samples can be taken from different people and a pooled sample is created. If the combined sample is negative, and it is a good test, then everyone is clear. If it returns a positive result, then the group is split repeatedly, using standard optimisation methods, until you find the persons who are positive. This process is already being trialled in hospitals in Germany.
Very helpfully, there is already a global database of test results being collected by FIND (Foundation for Innovative New Diagnostics) in Geneva. This database includes details of the target antibodies and detection process used by each test. By including each test’s accuracy, precision, and the cost of the testing kit, it could be used as a starting point to generate suggestions about which regime could be more effective for different countries.
If Amazon were to sell the tests, it could suggest the purchaser buy a combination of tests as a package to improve test efficacy. Amazon could even collect data on the test results through its platform. This information could then be shared with public health authorities to identify which individuals have been tested, and retested, and have found themselves to be positive.
If this was proved to be effective and successfully rolled out in the UK, we could use this method to contain the virus, providing a safe route out of lockdown and getting our withered economy back on track as quickly as possible. In addition, it could be a game-changer for developing countries which do not have the resources to fund or pay for the highly accurate tests.
Where countries have a severe constraint of a lack of time and a lack of resources, buying multiple, cheaper tests and combining them to increase accuracy, could be the answer to reduce transmissions and offer a more certain route into a post-pandemic future.
Similarly, a pooled approach could help health authorities in developing countries test large numbers of individuals and identify where the positive tests are located without using as many resources as when testing everyone separately.