By Natalie_l on Tuesday, January 15, 2008 - 1:32 pm:
My advice (as a scientist with a background in parasitology) is to avoid sushi unless it is prepared fresh (e.g. sushi bar OK, sushi from supermarket not OK). Listeria is a bacteria that is found in the environment, usually soil. It is killed by heating things to at least steaming hot, and unlike most bacteria, it can multiply (grow) even when in the fridge. That is why you are not supposed to eat raw, pre-prepared foods like salads and sushi but if you prepare these yourself, it is OK.
Personally, I avoided these foods in Japan and Australia (except a couple of times when I was tempted!). However I stopped altogether when I found out the possible effects:
"In pregnant women, however, even though the most usual symptom is a mild influenza-like illness without meningitis, infection of the fetus is extremely common and can lead to abortion, stillbirth, or delivery of an acutely ill infant".
Considering these things, I would only eat sushi if absolutely desperate for it, and only then from a very reputable place.
Hope this helps!