Just under 250,000 Italians have had confirmed cases of COVID-19, but a new survey released Monday suggests the actual tally is six times the official count.

Almost 1.5 million people (1.48 million), or 2.5% of the population, likely have coronavirus antibodies, according to the survey by Italy's health ministry and statistics agency, Reuters reported. That finding is based on testing of 64,660 people between May 25 and July 15. Of those tested, 27.3% were asymptomatic. Tests were done in partnership with the Italian Red Cross.

In 41.7% of the cases, the source of infection was a relative living in the same home, CNN noted. There were significant regional differences in the results, with the northern region of Lombardy reporting a 7.5% infection rate while the islands of Sicily and Sardinia reported just 0.3%.

"This means that the tough and rigorous measure adopted by the central and regional governments, and the correct behavior of the Italian people, avoided a more massive spread of the virus," health minister Roberto Speranza said at a news conference, per CNN.