EPIDEMIOLOGICAL ZONING OF THE REPUBLIC OF TAJIKISTAN IN ACCORDANCE WITH THE RISK OF HUMAN BRUCELLOSIS

Objective. Until the present time, the Republic of Tajikistan (RT) has lacked scientifically sound data on the risk of human brucellosis (RHB) in some administrative units (AUs) located in different altitude zones of the country that is why the aim of this study was to epidemiologically zone the territory of RT according to the degree of RHB. Materials and methods. To estimate the level of RHB, morbidity rates in the past 16 years were ranked by the method described by A.I. Kologorov and coauthors. Results. Fifty-nine of the 65 RT AUs were established to be involved in the epidemiological process of brucellosis: the latter was registered in 21 AUs during 15 and more years, in 28 AUs during 10 to 14 years and in 10 AUs during less than 10 years; only rare cases were notified in 6 A Us. Despite of the wide scatter of the RHB rates in the A Us, there is an altitude-specific tendency in the distribution of RHB rates in the risk groups. The plain zone is characterized by the highest involvement of AUs in the brucellosis epidemiological process (n = 39) with the wide distribution of AUs in all risk groups with a tendency toward the low (31%) and equal distributions of AUs in both the high, moderate, and intermediate risk groups (23% in each). In the piedmont zone, the epidemiological process involved 12 AUs with the highest representation in the moderate (33%) and intermediate (42%) risk groups with some tendency toward a high risk (25%) and no AU in the low risk group. The peculiarities of the mountainous zone are the least involvement of AUs (n = 8) in the epidemiological process and the equal distribution of AUs in all the high and intermediate risk groups with a tendency toward the low risk group (37.5%). Conclusion. The involvement of 59 of the 65 RT AUs suggests that the country is brucellosis-endemic. The wide scatter of RHB rates in all altitude zones of RT is evidence for the decreased influence of an altitude factor (the location of an AU in the definite altitude zone) on the epizootic and epidemiological manifestations of brucellosis due to the predominance of sparse private households over public ones that had been previously concentrated in the definite areas of RT.

Key worlds: brucellosis, zoning, risk, infection, Tajikistan