Virologists warn about the risks of the new phase of covid-19 in Italy.

Italy could face a second nationwide lockdown at Christmas, according to Padua University virologist and top coronavirus expert Andrea Crisanti.

"I think a lockdown at Christmas is in the scheme of things" - Crisanti said on 14 October - "As cases increase, the capacity for contact tracing and taking swabs decreases and we enter a vicious circle that increases the transmission of the virus."

Crisanti, a professor of microbiology, was speaking on television as a guest of Italian state broadcaster RAI News24.

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Crisanti said a Christmas lockdown in Italy could "lower the transmission of the virus and boost contact tracing."

"The virus must be stopped," said Crisanti, adding: "In 15 days' time I would not like to find myself discussing 10-12 thousand cases a day."

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Crisanti's warning was echoed by virologist and advisor to Italy's health ministry, Walter Ricciardi.

"A few days ago I predicted that if we had not taken measures such as those we are taking now we could have reached November with 16,000 cases" [per day, ed.], Ricciardi said on Tv2000.

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"In reality, the pace of growth is so strong that we could get there even earlier" - said Ricciardi - "So it is necessary to respect the old rules and introduce these new ones."

Italy has introduced fresh restrictions as the number of new covid-19 cases registered on 13 October climbed to 5,901.