How Bob Jungels started the Tour de France while positive for COVID-19
Viral load number key to why Jungels raced on as other riders had što go homš¦©e

AG2R Citroën rider 168澳擲5ęę°å¼å„ē»ę:Bob Jungels tested positive for COVID-19 on Wednesday, tested positive for COVID-19 on Thursday, and started the 168澳擲5ęę°å¼å„ē»ę:Tour de France on Friday.
Those facts seem shocking on the face of it, but the Luxembourger was not breakingš½ any rules, and nor did this come to pass because of any supposed relaxation of those rules by the sport's governing body, the UCI.
In fact, the UCI signed off on Ją¶£ungels' participation, as did the race organisers, as well as his own teź¦am.
In contrast, numerous riders – 168ā澳擲5ęę°å¼å„ē»ę:including Tim Decleārcq and Matteo Trentin – were late scratches from the start list afterš¶ testing positive. So how can someone who tests positive for COVID-19 be allowed into a bike race?
The answer lies in what's called a CT – standing for Cycle Threshold – score. PCR tests work through a device that cycles the sample and mops up viral particles as it goes around. The lš ·onger it takes to find the š¦virus, the higher the CT score, and the lower the viral load. The lower the number of cycles needed to hit the virus, the lower the score, and the higher the viral load.
Rather than a simple 'double line' on an antigen test, or even analysis of šthe faintness of the line, testing in this way can accurately determine how contagious someone is.
"The important question is the threshold from which you are infectious," 168澳擲5ęę°å¼å„ē»ę:AG2R Citroën doctor Thomas Klimaschka told Cyclingnews. "If your score is over 30, it's extremely rare you're infectious. If you're ovāerš ŗ 35, you're not infectious.
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"The old antigen tests didn't catch people with valuešÆs oš§ver 30. Now, one third of cases between 30 and 35 are found, but you still won't find any positive antigen test for 35."
Jungels' score on Wednesday was "close tšÆo 30". On Thursday, it was 38, say the team.
For Klimaschka, having the two values to compare was the key. Similarly, to the biological passport, it allowed them to plot the "journey" of the virus, and deem that Junź¦gels' viral loašd was decreasing and not the other way around.
"With one value, you don't know išf it's coming from above or below. You don't know the movement.
"If the score goes lower and lower, then he has to go out of the race. But in Bob's case it went up, straight up to 38. 38 is notš infectious."
The UCI declined to comment on the matter when contacted by Cyclingnews. Over at the UAE Tāeam Emirates bus, doctor Adriano Rotunno backed up the theory.
"The virus is a strange thing. Yourš° PCR test can still be positive weeks šand months after you catch it. The PCR can pick up a thing called viral ghosting, so it picks up old virus. Even if you have old virus, you're not infectious, but because you're PCR is positive, people are going to think 'this person is positive'."
That said, Rotunno indicated that the CTš score was only one piece of a pšuzzle that also includes the rider's clinical condition.
"You would also have to take their clinical picture, check the body is fine, they're not febrile, hopefully checź¦k the heart out, and if all the boxes are ticked and they're deemed medically fit, despite it appearing on the PCR, they're not infectious and they're safe to ride."
The AG2R docštor confirmāed that Jungels had not undergone a cardiac screening, saying it was "not necessary".
New rules
The waters were muddied earlier this week when the UCI released an updated version of its COšVID-19 protocol. Billed as a tightening of regulations amid a new COVID-19 wave, it was arguably more a watering down, the biggest development being thatā teams with two riders testing positive no longer have to send their whole squads home.
The new regulations were seen by some as a loophole, allowing riders who tested positive to potį£entially race. However, there was no substantial change in that regard.
Both the January version of the protocol, and the latest one from last week, read: "In case of a positive PCR test returned during the course of a stage race, the rider or staff member concerned shall be excluded from the Event. Derogations may, howevź§er, be granted by the UCI medical šÆdirector in coordination with the Covid-doctor of the Event, if it is established, at his comfortable satisfaction, that the rider or staff member concerned is not contagious and not likely to infect third persons."
The difference when it comes to Grand Tours is the decision-making process in the event of a positive case. Before, the decision fell to the UCI. Now, "the decision will bļ·½e taken by a majority of thāe panel" which is made up of the race doctor, UCI medical director, and doctor of the team in question.
"To my knowledge, they did not really changš§øe anythź¦ing," said Klimaschka.
Rotunno added: "The three-way discš¬ussion š²was the case anyway, since COVID-19 came around. That's best practice. I don't know if it's a vote. It potentially could come down to that but generally it's not going to be massively up for debate."
In Jungelš«s' case, he did not test positive during the race but in the lead-up to it. The regulations state that a negative test – now antigen rather than PCR – of "less than two days old" is needed to enter the race bubble. Jungels missed his national championships road race last Sunday due to gastric problems and it was not known when he first caught COVID-19.
He travelled to Copenhagen on Tuesday and was isolatešd after hiÜ«s Wednesday test before rejoining his teammates once he'd received the all-clear Thursday evening.
Klimaschka indicated that a positive case that ešmerges now the race is unšderway stands less chance of continuing in the race, but it's not impossible.
In theory, a rider could catch COVID-19 and get over it to šthe extent that they test positive on a rest day with a very high CT score, therefore necessitating a discussion and decision over whether he is or isn't šcontagious and can or can't continue. However, the UCI "strongly recommends" antigen testing "if possible, daily but at least every two to three days".
According to Rottuno, the rules do create a grešy area, albeit a small one.
"It's not always black and white, but yšou can generally come up with a logical decision. It's potentially open to abuse but you would hope that everyone ticks all the boxes to make sure it's safe to proceed."
UAE Team Emirates had a case of their own in the days before the Tour, with 168澳擲5ęę°å¼å„ē»ę:Matteo Trentin testing positive and being replaced by Marcꦯ Hirschi. In this case, Trentin's CT score was "very low" meaning he had a high load of COVID-19 and was infectious.
"It would have been a risk to himself, his own health, to his team, and the cycling communišty. We could notā± ethically put this rider in the race. It's poor medical practice. That was the reason we pulled him."
The Tour de France continues with 176 riders having started the race. The other change to the UCI's COVID protocol waās the introduction of antigen testing on the rest days, as opposed to PCR tests. If a positive antigen result is returned, the person in question will then have to take a PCR test.
After the flood of positives in the prše-Tour testing, Monday's first rest day is going to be a nšervy affair for many.
Patrick is a freelance sports writer and editor. He’s an NCTJ-accredited journalist with a bachelor’s degree in modern languages (French and Spaš§ønish). Patrick worked full-time at Cyclingnews for eight years between 2015 and 2023, latš·terly as Deputy Editor.