Health Secretary Matt Hancock admitted most of the nearly 16,000 people whose results went astray at the end of September had been contacted by the Test and Trace service by 9am yesterday

The Government has admitted its “world-beating” system was not told about up to 16,000 people who had tested positive until as much as a week later.

Experts believe each of those people will have come into close contact with an average of three people who should have been told to self-isolate.

It may now be too late to track down around 48,000 people exposed to the virus who may have already contracted it themselves and potentially infected others.

Health Secretary Matt Hancock admitted to MPs that just 51% of the 15,841 people whose results went astray last week had been contacted by the Test and Trace service by 9am yesterday.