THE number of people affected by an outbreak of disease caused by tainted McDonald’s salad has now grown to 395, according to the Centers for Disease Control and Prevention in the United States.

Sixteen individuals have been hospitalised, with cases recorded in 15 states across the US. The illness is caused by the Cyclospora parasite, commonly associated with contamination from faeces.

The infection takes at least a week or two to take hold, according to the CDC, and it may be up to six weeks before patients experience symptoms. The most common symptom is watery diarrhoea, although patients might also experience a loss of appetite, weight loss, cramping, nausea and fatigue.

According to the latest information from the CDC, romaine lettuce that tested positive was put into pre-made salad packages by Fresh Express in Streamwood, Illinois. Those packages were shipped to McDonald’s locations, although not to retail consumers.

However, romaine lettuce from the same batch was also packaged in pre-made salads by Caito Food of Indianapolis, Indiana. Those pre-made packages were shipped to locations nationwide.

The pre-made salads and wraps were produced between July 15 and July 18, 2018, and had a “Best By,” “Enjoy by,” “Best if Sold By” or “Sell By” date ranging from July 18 through to July 23, 2018, according to the CDC.

The CDC is advising anyone with an affected pre-made salad not to eat it and instead dispose of it or return it to the retail location. If you ate one of those salads and subsequently develop diarrhoea, the CDC suggests going to a hospital to be tested for Cyclospora.

McDonald’s locations have since been replenished with non-tainted salad, but the bad news is that, with the time lag between infection and onset of symptoms, even if the problem lettuce has been completely withdrawn, new cases may emerge for weeks to come.