The Dimension Data sprinter has not turned a pedal in anger since Milan-San Remo and had already been resting a recurring ankle injury before this latest setback.
The virus is known for inducing fatigue and recovery can take months, even though the team remains confident of an improvement in Cavendish’s condition over the next two weeks.
“Mark has been experiencing some unexplained fatigue during training. Recent blood analysis has revealed him to have infectious mononucleosis caused by the Epstein-Barr Virus,” Dimension Data said in a statement.
“Unfortunately, there is no effective specific treatment against the virus but rest will be required to aid his recovery. His training load and symptoms will be monitored very carefully and he will make a gradual, step-wise return to full training and racing.
“It is difficult to give an accurate estimate of when we can expect him back at full fitness but we are hopeful of a significant improvement of his symptoms over the next two weeks.
Cavendish had a massive season in 2016. With his ultimate focus on the Rio 2016 Olympic Games, he raced and trained on the track and won the world championships Madison with Bradley Wiggins and then silver in the Olympic Omnium.
In between he had arguably his best ever Tour de France campaign, winning four stages and holding the yellow jersey for one before abandoning to prepare for Rio.
The Tour de France, where he has won 30 career stages, again remains his ultimate goal, but if the condition persists he is likely to run out of time to make the 1 July start in Dusseldorf, Germany.
