Six Italian nationals have tested positive for the coronavirus in the city of Codogno, in the northern Lombardy region, local authorities confirmed on Friday morning.
They are the first known cases of local transmission of the potentially deadly illness within the country.
There are unconfirmed reports in Italian media that up to 14 people in total have tested positive for the virus in Lombardy, and two further cases in the Veneto region, though six cases remain confirmed by authorities at the time of writing.
The first person confrmed to have contracted the virus was a 38-year-old man was confirmed to have contracted the virus after meeting a friend who had recently returned from China, authorities said.
The man, now being cared for in isolation in hospital, is said to be in a “very serious” condition.
Soon after, two more people tested positive for the virus – the initial patient's pregnant wife, and another man he had come into contact with, the Ansa news agency reported.
Three more cases were confirmed on Friday afternoon, as health authorities in the town advised residents of Codogno and nearby Castiglione d'Adda to stay at home as a precaution and avoid all social contact.
Schools, bars, and restaurants have also been closed “until at least Sunday” as a precaution in Codogno, a town of 15,800 people around 60 kilometres south-east of Milan.
Around 250 people are now reportedly being tested for the virus in the area.
The first patient had dinner in early February with a friend who had just come back from China, according to Lombardy welfare councillor Giulio Gallera.
Police have reconstructed the man's movements over the last four days and are trying to find anyone he or his wife may have been in contact with.
The friend with whom he dined, meanwhile, has been taken to Milan's Sacco Hospital, where he is being kept in isolation.
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Authorities are reportedly considering the use of military facilities for quarantine.
Two Chinese tourists, from the virus epicentre of Wuhan, tested positive in central Rome in late January, and one Italian who returned from the Chinese city on a special evacuation flight repatriating 56 Italian nationals also tested positive for the virus a week later.
According to the WHO, more than 80 percent of patients infected with the virus have mild disease and recover, while 14 percent have severe diseases such as pneumonia.