Rats are extremely important pests. On the farm they eat and contaminate all kinds of stored products, eat many crops in the field, destroy fowl, eggs, and wildlife, and damage farm buildings. In manufacturing, processing and storage plants they damage merchandise, destroy food, damage furniture and contaminate food products. They often bite sleeping children and even adults. These rodents have caused more human death, misery and economic damage than any other group of vertebrates.

Rats are especially harmful to man and domestic animals as carriers of disease. Plague in its various forms has been spread by rats and infected fleas from rats for thousands of years. Murine typhus is spread by the lice, fleas and mites of rats. Other diseases include, but are not limited to, infectious jaundice (Weil’s disease), rat bite fever, trichinosis, typhoid, dysentery and rabies. All these diseases can be transmitted by other means, but the rat is an important potential carrier.

Rats are very adaptable in their habits and have no set pattern of behavior. As environmental conditions change, they modify their habits accordingly. Sanitation is the backbone of any successful control program. Elimination of shelter, food and water in combination with rat-proofing of the structure will help to discourage rats. Outside harborage areas should be eliminated as well.