Milan - San Remo, Tirreno-Adriatico and the Giro d'Italia are all under threat of cancellation following the coronavirus outbreak in Italy, according to race organisers.
So far three people have died and the number of cases of the virus in the country has passed 150, with Italian authorities imposing fines on anyone caught entering or leaving outbreak areas in the north of the country.
Schools and universities have been closed, Milan fashion week is being held behind closed doors and Serie A football games have been postponed. Now, Italian bike races also appear to be in jeopardy.
"We are very worried about the spread of the epidemic because the situation in Italy is really difficult," Mauro Vegni, the director of RCS Sport who organise a number of Italian races including the Giro, told Corriere.
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"Our first concerns are Tirreno-Adriatico and above all the Milan-San Remo, which is in less than a month, so there is no plan B. If the government confirmed the blockade of sport in Milan and in Lombardy we would be forced to cancel it, it makes no sense to move the start by 20-50 kilometres: the race has been the same for 110 years. I hope that the outbreak will be contained."
More worrying, there are just over two months until the first Grand Tour of the season, the Giro d'Italia, and Vegni has warned if the situation deteriorates the three-week stage race could also be at risk.
"At the moment I can't say anything about the Giro d'Italia but it is clear that if the virus is not stopped, the risk that the race cannot take place is there."
The coronavirus has already led to the postponement of a number of Chinese races, with some Chinese teams also pulling out of the recent Tour de Langkawi.
Despite other major sporting events being called off, including the Chinese Grand Prix, organisers of the Tokyo Olympics in the summer have said the cancelled of the 2020 Games is "not being considered".
