Professor Aiden McCormick:

The modelling study in the virus reference laboratory was done on the basis that they took blood samples which had been sent for various studies, but not for hepatitis C, and then tested them on an anonymised basis. So they had thousands of samples to try and figure out who were the undiagnosed proportion in the country, and using that with the people who have actually been reported giving an estimate in a country. Their figure was 20,000. Our internal figure is 20,000. We think 30,000 is an overestimate.