A team of 40 people, armed with just a single bar code and limited test data, spent days using "dogged determination" to track down the mystery person in the UK infected with the Manaus coronavirus variant.
Data analytic experts and laboratory and logistic resources were drafted in to help identify the individual who tested positive for the variant of concern, with the team narrowing in on them among thousands of potential households.
Three cases of the P1 variant, first identified in the Brazilian city of Manaus, were detected in England on 26 February, along with three more in Scotland.
A public appeal was launched for one of those people to come forward after they left no contact details. The P1 variant, which was also detected in