Basso tested positive on Saturday but has not displayed any symptoms.
Gianni Moscon, Filippo Ganna, and Salvatore Puccio all trained with Basso earlier this week and have been withdrawn from Sunday's race as a precaution, as have four staff members. They will all have to self-isolate for two weeks.
In a statement issued on Saturday, Team Ineos explained that Basso had tested negative for COVID-19 on Tuesday but, despite mostly training alone and staying at his home ahead of nationals, returned a positive test on Saturday.
Ganna won the Italian time trial title on Friday afternoon following the morning recon with Basso. They, along with Puccio, were set to support Moscon in Sunday’s road race but will now not be able to race for 14 days.
None of them were in Ineos’ plans for the Tour de France but they will all be unable to race the Settimana Coppi e Bartali in the first week of September. Nevertheless, their period of isolation will end in time for them to line up at Tirreno-Adriatico on September 7.
Basso is the latest in a string of COVID-19 positives over the past couple of days. Larry Warbasse (AG2R La Mondiale) tested positive on Friday, while Inge van der Heijden was pulled from the Dutch national road race on Saturday, with both cases also leading to knock-on withdrawals for riders they’d been in contact with.
The revised 2020 calendar is continuing, and the Tour de France begins next Saturday, with teams set to be expelled from the race if they report two positive cases in their bubble.
"Team Ineos today withdrew its riders from the Italian National Championship as a precautionary measure in line with Covid protocols after Leonardo Basso returned a positive test today. He has been and remains asymptomatic," read the statement.
"Apart from a visit for treatment on his knee at his local medical centre eight days ago, Leonardo has been at home in Asolo with his girlfriend and training alone over the last 10 days.
"He tested negative on Tuesday. He has remained at home and did not join the team at their hotel in recent days. However, he carried out the time trial recon with Filippo Ganna yesterday and went on a training ride with him, Salvatore Puccio and Gianni Moscon this morning. In line with protocols all four riders will now self isolate for 14 days.
"Four staff members will also self isolate as they are considered secondary contacts. Although they have been in contact with the riders wearing masks, observing social distancing and other protocols the team believes this to be a prudent precaution. We will also support Leo with any contact tracing with any friends and family as appropriate over the coming period."
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