They crawl around over any surface clean or dirty, they eat things that should not be eaten, they carry diseases, bite people and cause infections that can kill you.

 It is a common misconception held that rats and mice are both dirty and dangerous. This is mainly due to the spread of the plague, or black death, which was actually carried by the fleas that lived on wild rats. Wild mice and rats can carry mites and fleas which are likely to carry disease because of their surroundings, such as the sewers. Also, rats and mice, when wild are scavengers, in cities, as there are a lack of their natural food sources, therefore, they mainly have to survive on waste such as food leftovers in bins. This activity can cause problems with mess such as feaces, and bite damage to objects.

However, tame rats and mice are very clean rodents, and very friendly, if handled from a young age