The ministry of Health believes more than 90 per cent of those with Covid-19 in Spain have not been recorded. These include people who are not showing symptoms and the real figures could run into millions.
This week the ministry set out details of its controlled testing plan of 62,400 people, which will start next week and last three weeks. The tests will also show to what extent a "collective immunity" to the virus may have built up.
It has acquired five million 15-minute tests and is working on more of the more accurate but slower PCR tests.
It was also suggested that people may have to wear a face mask in the street as the virus stays in the air longer than thought.
Millions of masks are currently being made in Spain.