В мире научных открытий (Jun 2016)
ASSESSMENT OF EPIZOOTIC ACTIVITY AND EPIDEMIC RISK IN HEMORRHAGIC FEVER WITH RENAL SYNDROME FOREST FOCI OF PRIMORSKII KRAI
Abstract
In forest foci of hemorrhagic fever with renal syndrome (HFRS) of Primorsky Krai Amur and Hokkaido hantaviruses are circulated in the natural host populations – Apodemus рeninsulae and Myodes rufocanus. For forecasting of HFRS disease indicators of epizootic activity and theirs threshold values in rodent population dynamics had revealed. Material was obtained during 2001–13. Number of trap-nights was 33890. 2737 of A. peninsulae and 1643 of M. rufocanus were investigated. ELISA, RT-PCR, IFA were used for the detection of hantavirus antigen, RNA, antibodies/avidity. The parameters of epizootic activity on 100 t-n (N – population, ni – infected rodents, nai – individuals with acute infection) were offered. Results showed that the active foci of Amur-viral infection are located on slopes of a Ridge Sikhote-Alin. Epizootic activity in A. peninsulae populations has the expressed cyclicity: phase I is rise, II is high, III is decrease/low. The phases I/II are continued no more than year, the phase III is continued some years, defining period of epizootic cycle. In phase I the number of rodents with an acute infection was increased from summer by a late fall. In phase II the number of rodents with acute infection was considerable in spring/summer, decreased in fall more than in 3 times. On all phases of cycle the threshold indexes were considerable higher for A. peninsulae, than for M. rufocanus, showing the epidemiological role of its in forest ecosystems. HFRS disease in phases I/II of epizootic cycle in A. peninsulae populations had two peaks: during late fall-winter (≥ 37% of cases) and spring-first half of summer (≥ 55% of cases The obtained threshold indicators of active circulation of Amur hantavirus in population dynamics of natural host allows to predicting the periods of the increased risk of infection for people in HFRS forest foci.
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