Congrats on your pregnancy. I'm almost 5 weeks myself. In regards to the food thing- avoid anything deli cold meats or salads, cold "leftovers" from the fridge, uncooked egg (yes no runny eggs yolks....boohoo) so this includes homemade mayo/aioli (in NZ and Aus store brought mayo uses pasteurised egg yolks), soft cheeses (hard cheese is fine ie. cheddar, tasty etc.), uncooked parsley, sushi, cakes/buns muffins with custard or cream in it, any raw meat (including fish and seafood so all other meat has to be well done and not rare or partly cooked), and be careful with cooked seafood some can carry listeria even when cooked (I just avoid seafood altogether).
Also be aware that listeria (the bug that you are avoiding) can still grow in the fridge but very slowly so its suggested that you buy milk, cheese, yogurt in small amounts as once the packet is opened listeria can grow on the food. You should make sure you wash all fruit and veg before eating and reheat any cooked food left in the fridge to steaming hot (throw away if not eaten within 2 days). Any canned food taken out of the can and stored in fridge (ie, canned fruit, fish, meats etc) should never be eaten cold (so reheat to steaming hot) and again thrown away with two days.
Hope this helps. Your doctor/Mid wife should be able to give all this info. I have a list of things I can and can't eat on my fridge just to remind me even though this is not my first pregnancy. So should also come into the "due in april" thread as I'm guessing you must be due then. JUst click on "reply" at the bottom of anyones post to add a post to the thread.