The Tour de France sprint star has been struggling for some time
Mark Cavendish is to take an indefinite break from cycling after contracting the Epstein-Barr virus.
The British rider has been told to take a period of total rest and will not return to training with his Dimension Data team until he has fully recovered.
Cavendish said: “This season I’ve not felt physically myself and despite showing good numbers on the bike I have felt that there’s been something not right.
“Given this and on the back of these medical results, I’m glad to now finally have some clarity as to why I haven’t been able to perform at my optimum level during this time.
“Having received expert medical advice as a result of the findings I’ve been advised to take a period of total rest in order to fully recover.
“I’m now looking forward to taking the time necessary in order to get back to 100% fitness before then returning to racing again at peak physical condition.
“I’d like to thank everyone for the incredible support I’ve received and I look forward to seeing you all out on the road again soon.”