Particularly during pregnancy raw food or food that has not been heated sufficiently should be avoided. Raw vegetables must be washed thoroughly when they are being prepared. Consumption of unpasteurised milk and cheeses prepared from raw milk should also be avoided. In practice this includes Brie, Camembert, feta cheese, Coulommier, Reblochon, Vacherin and blue-veined cheeses. Yoghurt, Gouda-type cheeses and quark are safe in this respect. The quality control of foodstuffs should specifically include tests for Listeria bacteria. Remark : other disease which are "cheese-linked" are brucellosis which often occurs after eating contaminated goat cheese, and bovine tuberculosis, after drinking milk contaminated by Mycobacterium tuberculosis bovis. Q fever can also occur after drinking contaminated milk, but this is exceptional.