Genetic scientists mapping the spread of Covid-19 say that they have so far found 35 cases that may have led to the outbreak here.
ESR has been analysing virus samples to try to build a comprehensive picture of how it has spread through the country - and how it's mutated along the way.
The scientists' ultimate goal is to genetically map every single case which could provide invaluable insights in the fight against the disease.
RNZ's Matthew Theunissen reports.
