It is probable that it has an animal source, but whether it spreads from contaminated food or something else in the environment is unknown.

BBC: Threat from novel coronavirus 'remains low'

The bacteria exist everywhere in the environment but are commonly swallowed in contaminated food.

BBC: E.coli nursery gets all clear

The E.coli bacteria exist everywhere in the environment but are commonly ingested by contaminated food.

BBC: Two more in nursery E.coli outbreak

The Environment Agency said no signs of contaminated water from the fire had been found in the nearby River Wye.

BBC: Fire on Rotherwas Industrial Estate

Contaminated water levels at a flooded disused mine in mid Cornwall have improved, the Environment Agency has said.

BBC: An archive picture of Wheal Jane

The Environment Agency had to reintroduce oxygen in the canal to prevent more fish from dying due to the contaminated water.

BBC: Crews still at Stanton-by-Dale recycling plant fire