Cow Manure the Suspected Source of a Wave of Illness Ahead of Giro d’Italia

A wave of illness is sweeping through the peloton just days before the 2026 Giro d’Italia, and the suspected culprit is quite gross: cow dung.

If pro bike racing wasn’t dangerous enough as it is.

Riders are blaming mucky, grimy roads coated in manure at the Famenne Ardenne Classic last weekend in Belgium for a spate of stomach infections that’s zapping riders ahead of Friday’s start at the Giro.

According to Sporza, teams suspect cow manure coating some sections of the rain-soaked roads may be the source of the outbreak.

Wet conditions caused manure-coated muck to spray into the peloton.

Lotto-Intermarché sports director Kurt Van de Wouwer said the team believes the grimy race conditions triggered the bizarre wave of illness.

“There was cow shit on the road here and there on Sunday,” Wouwer said. “Because of the rain they are starting to splash up. So that could be the cause.”

Aches, fever, vomiting

Other teams also reported riders suffering from gastrointestinal symptoms following Sunday’s race in Belgium’s Ardennes region.

Winner Arnaud De Lie also fell ill shortly after his victory, Sporza reported.

Riders across several teams were hit with abdominal pain, vomiting, and fever, forcing last-minute lineup changes for anyone heading to the Italian grand tour, Sporza reported.

De Lie’s Lotto-Intermarché team was hit hardest, with Liam Slock forced to withdraw from what would have been his first Giro after he was unable to travel due to illness.

De Lie skipped Wednesday’s team presentation to recover, though team officials said he’s still on track to start Friday.

Medical staff have doled out antibiotics to impacted riders, but the timing is far from ideal ahead of the season’s first grand tour.

Giro organizers said the opening three stages in Bulgaria are dry and clear, and free of manure.