His team, Omega Pharma Quick-Step Cycling, said the 29-year-old will not race and will concentrate on getting fit for the Tour de France, which begins in Leeds on Saturday week.
“The current British champion is busy with a bout of bronchitis that began during the last stages of the Tour de Suisse,” said a team statement.
“As a precautionary measure Mark will not participate on Sunday and will continue training in Italy prior to the Tour de France.”
Cavendish was naturally disappointed but was not prepared to take any risks with the Tour de France less than a fortnight away.
“I’m sad because, as current champion, I would really like to defend the title,” he said.
“I would have liked to honour the race and this jersey that I wore for all of 2014 so far, which allowed me to represent my country proudly.
“I think it’s wiser, however, to not take any risks and focus on absolute, 100 per cent recovery, and continue to train in preparation for the Tour de France.
“I talked with the race organisers and they understood my situation perfectly.”