Prevention of infectious diseases is the leading direction in system of the Russian health care. It is provided with carrying out the broad improving preventive and anti-epidemic actions including and fight against rodents. Rodents are a natural source and a carrier of activators not less than 20 dangerous infectious diseases of the person and pets - plague, a tulyaremiya, leptospirosis, tick-borne encephalitis, a typhus, helminthic diseases, etc.
Typical representatives of rodents are gray and black rats; house, forest and field mice; voles; gophers. Rodents are widespread almost on all globe (excepting the Arctic and Antarctic), live in a natural environment. Rodents are gluttonous, some types are omnivorous (especially rats). At an opportunity use foodstuff of the person and his dwelling; thanks to it considerably expanded the natural area and live almost everywhere, settle in inhabited constructions, in warehouses, storages, railway transport and the ships. Distinguish the rodents living in the natural centers - "wild" and in the inhabited places - "sinantropny". In a warm season the part of sinantropny ("city") population of rodents is settled on open natural sites and the vacant territory around buildings, and with cold weather approach comes back to various constructions again. Rodents are very prolific, some types in the nature can breed during the whole year. Under favorable conditions for wintering and abundance of a forage are possible mass reproduction when the number of rodents reaches the huge sizes. All "city" rats and mice living in rooms breed all the year round. Fight against rodents, in particular with rats, was carried out for several thousand years. However centuries-old extermination of rodents practically did not affect their number and prevalence in the modern world. Today rodents (especially rats) keep great medical value for the person and everywhere cause economic damage to a national economy. "Wild" rodents exterminate agricultural crops and production, but for the person sinantropny rodents have major importance. City rats and mice do huge harm: spoil, eat, pollute food; put out of commission various materials (paper, a cardboard, skin, a tree, other construction materials); damage devices, rooms, constructions. Sinantropny rodents, contacting with "wild" (generally during the summer period), catch zoonozny infections and bring them to rooms, bringing closer a source of diseases to the person.