Tour de France 2022 route: When the race starts, a guide to each stage, and how to follow live on TV

Hopes of a fully fit line-up at this year's Tour de France are hanging by a thread after an outbreak of Covid-19 cases tore through the Tour de Suisse peloton.

Overall leader Aleksandr Vlasov, three teams and about 30 riders were forced to pull out of the Tour de France warm-up with Vlasov's team Bora-Hansgrohe saying he and team-mate Anton Palzer had tested positive.

The UAE Team Emirates, Alpecin-Fenix and Bahrain Victorious teams also withdrew, one day after the Jumbo-Visma squad left the eight-day race, which finishes Sunday.

"In the interest of the health of all riders and staff at the (Tour de Suisse), leaving the race is considered the most sensible decision by the team management and medical staff," Alpecin-Fenix said.

Four positive tests, including 2012 Olympic road race silver medalist Rigoberto Uran, were detected among the Education First squad in Friday morning tests.

Swiss rider Marc Hirschi and Diego Ulissi also tested positive in the UAE squad, which cited "team safety reasons and the wider cycling community" for leaving the race.

Ineos Grenadiers have also lost Adam Yates and Tom Pidcock who both tested positive for Covid with the former Yates nominally the team leader at the Tour, and Pidcock hoping to make his debut there.

The Swiss race is one of the last events to prepare for the three-week Tour de France, which starts in two weeks.

Why, it's only the 109th edition of the Tour de France, one of the three grand tours, the others being the Giro d'Italia and Vuelta a España.

Regardless of what some believe, this is the biggest and brashest bike race in the world, with an estimated 80 per cent of most WorldTour team's sponsorship income being based around the Tour.

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