More than 220 people have come down with the virus since Friday, latest data showed, the vast majority of them in the wealthy regions of Lombardy and Veneto.

Authorities across northern Italy have shut schools, universities, museums and cinemas for at least a week, and banned public gatherings including the famed Venice carnival.

Ten towns in Lombardy close to Italy’s financial capital Milan, with a combined population of nearly 50,000, have been placed under effective quarantine, with similar measures in place for a small town in neighboring Veneto.

“To be honest, nobody thought the spread (of coronavirus) would be so aggressive. The illness is not serious, but it must not be underestimated,” Attilio Fontana, the regional governor of Lombardy, told 102.5 RTL radio.

He added that emergency measures imposed at the weekend would be effective and that “in a matter of days, the spread of the virus will regress”.

Analysts warned that the outbreak, which is centered on the country’s industrial and financial hearlands, could shunt Italy’s fragile economy into its fourth recession in 12 years.

Italian shares were down 4.68% at 1300 GMT, with businesses most at risk from an expected spending slump worst hit. Electronic payments group NEXI lost more than 6.7%, while motorway and airport retail group Autogrill slumped 12.5%

Local authorities announced two new deaths on Monday, both men in their 80s from Lombardy. The three previous fatalities recorded since Friday were also all elderly and most of the dead had serious underlying health problems.

Lombardy remained the worst hit region with some 172 confirmed cases, while neighboring Veneto had 27 infections, including two in Venice which has been packed for the carnival season.

Officials said 23 people were in intensive care, while almost 100 were being taken care of in their own homes, with some of them showing little or no outward symptoms.

Milan, a city of 1.3 million people, was much quieter than normal for a Monday morning. Trials were canceled, some supermarket shelves were empty, and even the city’s imposing Gothic cathedral closed its doors, disappointing tourists.

“We were only meant to spend three days in Milan and then go to Venice for the carnival but everything is shut,” said Russian tourist Violla Belova, 50, wearing a face mask as she took photographs of the shuttered Duomo cathedral.

“I hope we won’t have to cut our trip short,” she said.

With other countries looking to prevent the spread of coronavirus, Mauritius on Monday told passengers from Lombardy and Veneto aboard an Alitalia aircraft that they would either have to go into quarantine or else fly straight back home.

Alitalia said 40 out of the 224 passengers and crew were affected by the ban and decided to leave the Indian Ocean island immediately.

Ireland said its citizens should not travel to parts of Italy affected by the outbreak. Tunisia announced on Monday that it may suspend some flights to Italy to reduce its exposure to the coronavirus.

Austria briefly blocked a train from Italy at its border on Sunday because of concerns over the health of two travelers.

Italy’s tourism industry, which accounts for up to 13% of the gross domestic product, sounded the alarm bell.

“We have been swamped by cancellations in the last few days, in restaurants, hotels, everywhere,” said Patrizio Bertin, the head of the Veneto branch of Italy’s trade lobby Confcommercio.

Marco Michielli, head of Veneto’s hoteliers’ association Federalberghi, said cancellations were “raining down all over the region, like in the rest of Italy,” and criticized the draconian measures adopted by the authorities.

“I think the government has been excessively prudent, to use a euphemism, it’s as though there were an Ebola epidemic.”