Officials in Rome said the capital region recorded 215 new coronavirus infections in the same period mainly because of people returning from holiday, the biggest such rise since lockdown in March.
The health ministry said Italy recorded 1,071 new cases of the novel coronavirus in the last day and three deaths, for the first time crossing the threshold of 1,000 infections since May 12.
It marks a relentless uptick in cases in the last few days, from 947 on Friday, 845 on Thursday and 642 on Wednesday.
The figure of 215 for Rome is a record, more than the 208 people were infected in a one-day period on March 28, when Rome had come to a virtual standstill to stop the coronavirus spreading, the capital's health official Alessio D'Amato said.
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“Sixty-one percent (of the cases) are linked to people returning from vacation,” D'Amato said, almost half the cases were returning from the island of Sardinia.
Sardinia had been spared the first wave earlier this year but D'Amato said the movement of tourists and people partying had helped spread the virus.
Francesco Vaia, director of Rome's Spallanzani Hospital specialising in infectious diseases, told Italian media “the solution is to do tests on departing boats, planes and trains. This is the only way to prevent the virus spreading”.
D'Amato said most of those infected were young people who were not showing symptoms and it was urgent to “block the chain of transmission as fast as possible by finding the asymptomatic and averting the spread of the virus among families.
“Be very careful especially with your relatives and the people dearest to you,” he said in an appeal to the young.
He warned them to stay at home and not meet up with people while awaiting test results. “Don't feel invincible,” he urged them.
Italy — particularly the northern Lombardy region, the Venice area and Rome — are seeing a resurgence in the virus over the summer.
The Italian government has taken several steps to block the spread, such as closing nightclubs since August 17 and making mask wearing compulsory in busy public spaces between 6 pm and 6 am.
Since the pandemic erupted, Italy has recorded more than 257,000 cases, including more than 35,000 dead.