I'm 19wks pregnant and have eaten out on several occasions, I have ordered salads (which may or may not have been washed) and didn't really think twice about illnesses like listeriosis, now I have read up on it, I feel a little anxious as apparently there can be no symptoms of this illness. I am now worried about the foods I have consumed in the past. How worried should I be, it is a very common illness? Is it really best to avoid eating out altogether? Does occasional loose stools mean that the food you have eaten has been contaminated?