There are many types of pest from the furry kind to the creepy kind and we all tend to have a natural aversion to them. People are scared of mice because for 1000s of years having pests around us is known to be a bad thing. These days the thought of rats in our house is even more awful than perhaps it was 2000 years ago and if we have children it pushes the levels of revulsion up even more! But how do we know we have a problem; does it matter and what do we do?