The German sprinter struggled through the Tour of Qatar but then withdrew from the Tirreno-Adriatico stage race, where he was set for a much-anticipated showdown with Mark Cavendish.
"It's not good yet," Kittle's race coach, Marc Reef, told Cycling Weekly. "He's just begun on the bike again, so he's re-starting to get better. He's not completely recovered. It's a shame that it happens."
Kittel's highlight of the season so far was the first time that he pined on a race number on January 18, when he won the People's Choice Criterium ahead of the Tour Down Under.
When he flew back from Adelaide, something was not right. He had a blocked nose, coughing and sneezing, which forced him to miss six to seven training days ahead of the Tour of Qatar. He raced in Qatar, but he paid dearly.
"We didn't think it was that serious. He was not up in the sprints in Qatar, but those were hard stages and we thought nothing of it in the beginning. Then in the last stage, it wasn't that hard, but he got dropped... then we thought something was wrong."
Giant and Kittel continued to push ahead towards this week's Tirreno-Adriatico in central Italy, but after some more training and disappointing results, they changed plans. Team doctor Anko Boelens and trainer Adriaan Helmantel decided it would be better to hit reset and let Marcel completely recover.
"We said, stop completely for one and a half weeks and re-start," Reef explained. "He's now easily restarting and getting better.
"He got rid of the virus. The coughing and sneezing went away, but your energy can be down for a longer period,” Doctor Boelens said. “You can never really predict how long it will affect you. We are going to take a couple of steps back before he rebuilds. Maybe a couple of weeks is enough, but sometimes it takes more time. We just have to wait."
Kittel ruled the Tour de France sprints last year by claiming four victories. 2015's early races were meant to be steps towards this year's Tour, as well as a chance to add to his palmarès, but now the situation changes. Instead of aiming to race and win Ghent-Wevelgem on March 29, Kittel is simply training to be able to participate at a decent level. The Scheldeprijs, where he won in 2012, 2013 and 2014, ought to come next.
"You can say it [will affect him for the Tour] or you can say he's now having a period without racing, a more relaxed period,” Reef added. “You see when guys have a break in the spring, they are fresher in July. That could be an advantage. But only when he's on a normal way back can we make a plan for the Tour."
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