Lazio records 75 new coronavirus cases on 19 August with 23 of them linked to Sardinia.

Italy on 19 August registered the sharpest rise in the daily caseload of covid-19 cases since 23 May, with 642 infections over the previous 24 hours, according to figures released by the Italian health ministry.

This figure was 239 higher than the day before, and represents the biggest daily increase since the 669 cases recorded on 23 May, reports Italian news agency ANSA.

There were 71,000 swab tests made on 19 August, an increase of almost 20,000 from the day before, the ministry said, with an additional seven people dying with the virus, up from four on 18 August.

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The biggest rises in cases were in the northern regions of Lombardy (+91) and Emilia Romagna (+76) while the central Lazio region, which includes Rome, recorded 75 new cases on 19 August, two thirds of which were "imported."

Many of these so-called imported cases are being picked up at Rome's Fiumicino airport where testing on people arriving from 'at risk' countries began earlier this week.

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The health councillor for the Lazio region, Alessio D'Amato, said that the number of imported cases included 23 from Sardinia where a new covid-19 cluster can be traced back to a party held on 8 August at the resort of Porto Rotondo.

Health authorities on the island have isolated 470 people, and, out of the first 300 swab tests taken, 21 people have come back positive.

The news comes days after Italy ordered the closure of nightclubs and tightened rules regarding the wearing of masks at night time.