Professor Mark Ferguson:

The existing tests detect all variants but they do not distinguish between them. The reason for this is that the antibodies are detected at what is called the nucleocapsid of the virus. This is the bit that does not change much. The good news is that the test will tell one whether the virus is present, but it will not tell one if it is a variant. The strategy would be for those who tested positive on an antigen test to take a confirmatory PCR test, from which the virus would be sequenced, allowing us to know what variant, if any, was present. The trick behind the testing is twofold. First, it will allow an awful lot of people to be screened very quickly and cheaply. Second, it will allow those who test positive to be isolated very quickly. That is the most important thing if this system is to substitute for hotel quarantine. One gets the result within approximately 30 minutes. People who test positive should isolate until they get a confirmatory PCR, after which they may need to continue to isolate. Rapid isolation is the trick. That will allow this system to be substituted for quarantine. Of course, compliance will be important. That is why I really believe that we need to do these pilots at scale so we can get the data, see what they look like and see if this could be deployed more widely.