PARIS-French food safety inspectors failed to detect salmonella contamination at a plant belonging to dairy giant Lactalis, three months before the company carried out a major recall of baby milk, a report said Wednesday.

Lactalis, one of the world’s largest producers of dairy products, discovered the bacteria at its factory in Craon, northwest France, during tests in August and November. It did not however report the find to the authorities. Officials from the food safety department carried out a routine inspection of the site in September and gave it a clean bill of health, the Canard Enchaine investigative weekly reported. It was only three months later, after around 30 infants being fed Lactalis powdered milk fell sick, that the health ministry sounded the alarm. Officials from the national anti-fraud bureau swooped on the site on December 2 and found the assembly line where liquid milk is transformed into formula to be contaminated. Lactalis issued two major recalls covering all production from the site from February 15, blaming the contamination on renovation work.

The plant has been at a standstill since December 8.

Salmonella symptoms include severe diarrhoea, stomach cramps and vomiting. The illness, caused by intestinal bacteria from farm animals, is especially dangerous for the very young and elderly because it can cause severe dehydration. The product recall, which included the Picot and Milumel brands, affected consumers in countries as far afield as China, Pakistan, Bangladesh, Britain and Sudan.