Chaves has looked back to his best at Giro d'Italia after winning stage six to Mount Etna and staying in the top-three overall until stage 10 of the race.
On that day, the first stage after the rest day, the Colombian lost over 25 minutes to the overall leader and his team-mate Simon Yates after he was dropped on the opening climb right at the start of the stage.
Chaves struggled to make an impact from there for the rest of the race, eventually finishing the race well over three hours down on race winner Chris Froome (Team Sky).
Since finishing the Giro, the 28-year-old took an extended period of rest after being diagnosed with the viruses. He has now been given the all-clear to return to training, but Mitchelton-Scott said they would remain cautious over his return to full fitness. Chaves had been scheduled to ride at the Vuelta a España starting on August 25, but won't take to the start line in Malaga, with his team unable to confirm if he'd race again in 2018.
“It’s been a hard period," Chaves said. "Since 2012 I haven’t been off the bike this long, especially because I can’t. It was not fast like you want. In this sport, we are used to answers and results coming fast and this process was slow and the time can make you crazy.
“But, we worked really well with the team and I want to thank you them for their support and patience, from the head with Shayne and Gerry, to the masseurs and mechanics that have been close to me in this process.
“We discovered some sickness, the doctors can always explain better, we had a surgery as well, and after that it was just waiting and having confidence to overcome what was a weird case.
“I’m happy to be back on the bike. It still hurts for sure, but I can already feel some differences; it’s a different suffering than I had before. Now it’s the normal suffering we get when starting again after such a long time off training.
“We are on the right path again and we have to keep patience and confidence like always.”
“After thorough testing, Esteban was diagnosed with Epstein-Barr virus as well as chronic sinusitis process," Mitchelton-Scott doctor Manuel Rodriguez explained.
“Epstein-Barr is not a new virus nor an uncommon one, but Esteban's tests showed that it was gaining strength and attacking when his immune system was down or in times of fatigue, most obviously in races or high intensity training periods. Its strength likely allowed the introduction of other viruses into his body.
“After a period of rest and treatment for the viruses, Esteban was cleared for minor sinus surgery before undertaking a final recovery period.
“We are confident that the treatments have been successful and it is safe for Esteban to return to training but to prevent the reoccurrence of symptoms we will monitor his health without a deadline to return to racing.”
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