From Big Medical Encyclopedia

NOZOAREAL (grech, nosos disease + lat. area area; synonym area of a disease) — set of territories of the globe, on to-rykh there are centers of a certain disease. Because N. of infectious and epidemic diseases are most studied, in literature «nozoareat» a concept use more often only concerning these diseases.

The term «area of a disease» for the first time applied E. N. Pavlovsky (1944, 1954), «nozoareat» — A. A. Shoshin (1962). N — the major concept nozogeografiya (see). The doctrine about N. gained the greatest development in the Soviet Union thanks to works E. N. Pavlovsky, V. N. Beklemishev, A. G. Voronov, A. A. Shoshin and other Soviet scientists.

At N.'s antroponoza matches an area of the activator, at zoonoza the area of a disease of people is, as a rule, more limited, than an area of the activator (especially at zoonoza of wildings) as the disease of the person arises only on that part of an area of a zoonosis, in limits the cut occurs process of interaction between people and a disease-producing factor.

N.'s borders are mobile, depending on natural and social conditions of spread of a disease they extend (the progressing N.) or are narrowed (the regressing N.). In case of bystry change of process of expansion and narrowing of borders speak about the pulsing N. (e.g., an area of the Japanese encephalitis). In a form continuous (e.g., an area of dysentery), broken off (an area of yellow fever in Africa and South America), tape (an area of an opisthorchosis), etc. distinguish N. Many antroponoza (flu, etc.) and a part of zoonoz (e.g., a trichinosis) are widespread everywhere — have global N., others (leyshmanioza, a local craw) do not go beyond a certain zone — zone N., nek-ry (the Japanese schistosomatosis, Kashin's disease — Beck) are dated for limited areas — regional N. If were never carried out to N. corresponding protivoepid, actions, designate it as initial (an area of a toxoplasmosis). The N significantly reduced under the influence of activity of the person designate as residual (e.g., an area of malaria).

The loudspeaker H. it is characterized, as a rule, by expansion to limit borders due to dispersion of causative agents of diseases by the migrating people (animals). The N tends to expansion across the territory, on a cut there are favorable ecological conditions for the causative agent of this infection or an invasion. So, malaria by the beginning of 20 century occupied practically all territory where there were mosquitoes of the sort Anopheles and a necessary minimum of heat for closing of the circuit of development of a malarial plasmodium in a body of a mosquito. Under influence protivoepid, N.'s actions of the majority of infectious diseases are narrowed. However activity of the person can promote also further expansion H. of nek-ry infections and invasions. So, in developing countries construction of water reservoirs and irrigational systems quite often is followed by emergence of the new centers of shistosomatoz and malaria.

N.'s territory is heterogeneous on structure. Usually N.'s territory is subdivided into sites of similar influence of the environment, edges are defined by a structure parasitic system (see), intensity of reproduction of the activator, stability epidemic process (see), seasonality of transfer of contagiums, and also the damage caused by a disease-producing factor to people. So, N. of many parasitic diseases on the level of a prevalence of the population (or on the level of intensity of transfer) subdivide on hypo - meso - and hyper endemic sites. In N. of prirodnoochagovy infections allocate epidemiol. areas, provinces, districts, districts, sites.

The most important condition of studying of N. is completeness of identification and the accounting of diseases of people, emergence to-rykh spread of diseases among animals, knowledge of areas of animals — tanks of contagiums, and also areas of carriers and intermediate owners is connected with stay in this area, and.

For N.'s studying use epidemiological and geographical, in particular cartographic, methods.

See also Geographical pathology , Geography medical .

Bibliography: Geography of prirodnoochagovy diseases of the person in connection with problems of their prevention, under the editorship of P. A. Petrishcheva and N. G. Olsufyev, page 5, M., 1969, bibliogr.; Lysenko A. Ya. Nozoareal and his structure, in book: Medical geography, under the editorship of A. E. Belyaev, etc., century 2, page 18, M., 1967; Prirodnoochagovy diseases of the person, under the editorship of E. N. Pavlovsky, M., 1960; Shoshin A. A. Fundamentals of medical geography, page 93, 109, M. — JI., 1962.

A. Ya. Lysenko.