It starts with coughing and sneezing, is followed by stomach problems, and ends up forcing you out of the race. That's not Covid, but the bug which swept through Paris-Nice, decimating the field, leaving just 59 riders to cross the finish line on Sunday.
To put that in perspective, the 2020 Covid-affected edition saw 17 teams take part after seven WorldTour squads pulled out at the beginning of the pandemic, and two more left left mid-race, but still 61 riders finished.
In fact, the last time fewer riders crossed the finish line in Nice was 1985, one of the seven won by Sean Kelly that decade. The winner of the final stage, Simon Yates, was the only one of his BikeExchange-Jayco team to finish.
The hollowing out of the peloton was exemplified by Bora-Hansgrohe not finishing with a single rider, as Ryan Mullen, Sam Bennett, Aleksandr Vlasov and Danny van Poppel all pulled out on the final stage.
AG2R Citroën Team, B&B Hotels-KTM, Cofidis, EF Education-EasyPost, and Lotto Soudal finished with two riders each, while Astana Qazaqstan Team, BikeExchange-Jayco, Intermarché-Wanty-Gobert, Israel-Premier Tech, and Quick-Step AlphaVinyl only finished with a single rider.
Matthew Holmes of Lotto-Soudal signed on in Nice on Sunday, but shortly after told journalists in the mix zone that he had the cold, "the one that everyone else seems to have", and so might not start the stage. He did not, describing it as "pretty miserable".
Hugo Houle of Israel-Premier Tech was on his own from stage five, telling Cycling Weekly after stage six that he was "super tired" but fine "in the circumstances".
"I'm happy to be here," the Canadian said. "I lost all my friends, but I'm just feeling lucky to be here. Every day is a bonus, today I felt good again. I'm riding well now, so far so good. Always fingers crossed, I didn't know there was a virus around. You go day by day and hang in there."
By the end in Nice, he sounded wearier but defiant: "It's going well. I'm feeling good, really motivated. I don't like the rain but I think these conditions suit me really well. Never give up, anything can happen. I'm just going to go out and give everything I've got." He finished 25th on the final stage and 13th overall.
His DS, Steve Bauer, successfully avoided the virus that had brought down most of his team. He said: "Hugo is riding really strong which has been a battle for our team. We've had gastro problems, sinus problems, lung infections, painful backs. We're really suffering."
Just 11 teams out of the initial 22 were included in the final team rankings, as the competition is calculated on a team's top three finishers overall. Alpecin-Fenix finished 11th, but jumped up eight places on the last day thanks to others dropping out.
Simon Carr of EF Education-EasyPost was another to start the final stage but not finish; he predicted that this might be the norm for races at the start of the season. Weakened immunity has been something blamed, including by his team boss Jonathan Vaughters.
He tweeted last week (opens in new tab): "Our teams in both Tirreno and Paris-Nice are getting chopped to pieces by the good old fashioned flu. Fever, chills, etc, but COVID negative. I think we all forgot about the flu and probably have reduced resistance to it because of isolating ourselves the last few years."
"It's a bit different to what it was like last weekend," Carr said at the start of stage eight, perhaps underselling the change. "It's actually pretty nice, racing aggressively, getting in the breaks. It's a bit more relaxed I guess as well, it's different but it's nice. Especially if you're in the break, and then you come back to the bunch and the bunch is not that much bigger. It's a bit of a strange one, but I think Tirreno is also the same, so maybe a lot of races are going to be like that."
For others, however, this was almost business as usual at Paris-Nice. Ryan Mullen of Bora-Hansgrohe did not manage to finish the final stage, along with all three of his team-mates, but he said it was "just the time of year".
"It's just the time of year, everyone is susceptible," the Irishman said. "It's just a hard race. You start in the cold, and it's the first proper hard race of the year. This race is actually notorious for people dropping out with illness and injuries, it's just the time of year. Last time I did this was 2020 and it was even worse. It is a bit strange, the peloton gets smaller every day but it's just the time of year.
"If you're coming down with something, with the races coming up, you have to make an educated decision and not push your body too hard," Mullen explained. "Because Milan-San Remo is in seven days. If you nip it in the bud two days before the end of the race you'll survive the Classics whereas if you push through you're probably floored for the week. Staying warm, that's the main aim."
Now these riders have been exposed to the bug once, it might be that they are more resilient for the rest of the year. However, as we move towards a post-Covid world, the threat of illness still hangs over the bunch at stage races.
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