[Spatial structure of natural foci of hantavirus on the territory of Northwestern Caucasus].

For the period from 2001 to 2011 zoological and epizootological studies in more than 100 points of Northwestern Caucasus including territories of Krasnodar Region and Republic of Adygea were carried out. 8723 specimens of small mammals represented by 20 rodent species and 7 insectivorous species were captured and examined. Organs and blood from 5057 specimens of creatures were studied for hantavirus infection. The presence of natural foci of circulation of 2 species of hantavirus--Dobrava/Belgrade and Tula--was established. Sochi viruses and presumably Kurkin with main natural hosts--Caucasian wood and field mice belong to the first species. Tula and Adler viruses with the main host--Microtus genus vole belong to the second species. Quantitative characteristics of infection of small mammals of various species during different seasons and years on the examined territories were obtained, that allowed to create a map of allocation of foci of hantavirus circulation that differ by structure.

[On the taxonomic rank of ciscaucasicus and its relationships with the pygmy wood mouse Sylvaemus uralensis inferred from the mtDNA cytochrome b gene sequence].

To specify the taxonomic rank of form ciscaucasoides (independent species Sylvaemus ciscaucasoides, or intraspecific form of pygmy wood mouse, S. uralensis), a 402-bp the mtDNA cytochrome b gene fragment (402 bp) was examined in S. ciscaucasoides individuals from six geographic localities of the Caucasus and Ciscaucasus, (Krasnodar krai and Adygeya Republic) and 17 S. uralensis individuals from seven localities of the Russian Plai (Saratov oblast, Smolensk oblast, Voronezh oblast, Tula oblast, Moscow oblast, and Tver' oblast). For comparison, the cytochrome b gene was partly sequenced in the samples of yellow necked, S. flavicollis (n = 2, Samara oblast), and Caucasian, S. ponticus (n = 6, Krasnodar krai), wood mice. One Mus musculus specimen from Western Europe, whose nucleotide sequences were deposed in the GenBank, was used as intergeneric outgroup. Phylogenetic trees for the forms examined were constructed based on the mtDNA sequence variation and using the neighbor joining and maximum parsimony methods. The network of the cytochrome b haplotypes was also constructed. The level of genetic divergence was evaluated using Kimura's two-parameter algorithm. Based on the data on the sequence variation in a 402-bp mtDNA cytochrome b gene fragment, the hypothesis on the species status of the ciscaucasicus form was. The mean intergroup distances (d) between the geographic groups of S. uralensis varied from 0.0036 to 0.0152. At the same time, the distances between the pygmy wood mice and the group of S.flavicollis-S. ponticus varies in the range from 0.0860 to 0.0935, and the level of intergeneric genetic differentiation (Sylvaemus-Mus) is higher than the latter index (d = 0.142). Ciscaucasoides should be considered as geographic substitution form of S. uralensis. Furthermore, the Caucasian populations of S. uralensis (= ciscaucasoides) were characterized by a threefold lower value of intergroup genetic divergence (d = 0.0062) than the East European populations (d= 0.0179). This finding pointed to some isolation of Caucasian populations of pygmy wood mouse and depletion of their gene pool. However other molecular genetic data (similarity of nucleotide composition and consistence of the levels of intra- and intergroup distances) suggest the absence of geographic subdivision between Caucasian and East European populations ofS. uralensis relative to the molecular marker examined.

[Epizootology of hemorrhagic fever with renal syndrome in the Central Chernozem Region].

A total of 5149 small mammals belonging to 16 species were collected from the Lipetsk, Voronezh, and Belgorod regions (40 administrative districts) in 2003-2004 and examined by ELISA and IFA to detect hantavirus antigen and antibodies in the lung tissues. Hantavirus circulation was revealed in 13 species, the highest hantavirus activity being detected in field (Apodemus agrarius) and small wood (A. (S) uralensis) mice (Dobrava-Belgrad virus), bank (Clethrionomis glareolus) (Puumala virus) and common (Microtus arvalis) (Tula virus) voles. These species were frequently found to have their untypical hantaviruses, which was most commonly observed in small wood mice. It is suggested that the small wood mouse is likely to take a certain part in maintaining the circulation of Dobrava-Belgrad virus.

[The epizootological and virological characteristics of a natural hantavirus infection focus in the subtropic zone of the Krasnodarsk Territory].

A natural focus of hantavirus infection was detected and examined during the studies conducted in 2000-2002 around the Sochi (the western spurs of the Great Caucasus Ridge, which descended to the Black Sea (the Krasnodar Territory of Russia). At least 4 rodent species, such as Microtus majori, A. (S.) ponticus, A. agrarius, A. (S.) ciscaucasicus, were shown to participate in the circulation of hantaviruses. A comparative analysis of the nucleotide sequences of genomic S- and M-segments of hantaviruses has provided evidence that 13 viral RNA isolates from the A. (S.) ciscaucasicus belong to the Dobrava/Belgrade virus clade; however the RNA isolate from the Microtus majori belong to the Tula virus clade.

[A burrow of a little ground squirrel as a consortium]. / Nora malogo suslika kak konsortsiia.

Structure of consortia as an animal community inhabiting a mammalian burrow with an example of the little souslik Spermophilus pygmaeus Pallas from Western Kazakhstan was studied. Species composition, numbers and distribution of invertebrates in different types of burrows and nests of the little souslik were examined on the background to their food dependencies on the host. The consortia is considered as a system of concenters around the host of burrow (center of community, CC). Recognized concenters are given with ranks based on food relations between invertebrate inhabitants and CC: concenter of I rank includes direct parasites and predators of CC, II rank is represented by consumers of dead bodies of the souslik and its life activity products; III rank includes predators and parasites of souslik's cohabitants, and concenter of IV rank encompasses animals, which use the burrow as a refuge only. Within limits of each concenter, a number of "rondos", groups of animals attributed to certain systematic category, for example ticks, gamasid mites, certain insect orders etc., may be recognized.

[Long-term dynamics and prognosis for tularemia and pseudotuberculosis morbidity in the Iaroslavl region]. / Mnogoletniia dinamika i prognoz zabolevaemosti dlia tuliaremii i psevdotuberkuleza v Iaroslavskoi oblasti.

The trends and main factors influencing the fluctuations of the levels of tularemia and pseudotuberculosis morbidity in the Iaroslavl region were revealed by the methods of mathematical statistics (regress analysis, time-series analysis, etc.). Tularemia morbidity was 0.467 +/- 0.216 cases (1950-1997) and pseudotuberculosis morbidity was 0.979 +/- 0.297 cases (1979-1997) per 100,000 of the population. The multiple regression equations permitting the prognostication of tularemia and pseudotuberculosis morbidity in the Iaroslvl region were derived.

[The antimicrobial activity and acute toxicity of the polymer salts of gentamycin]. / Issledovanie antimikrobnoi aktivnosti i ostroi toksichnosti polimernykh solei gentamitsina.

By neutralization of copolymers of N-(2-hydroxypropyl) methacrylamide with acrylic acid and copolymers of N-vinylpyrrolidone with crotonic and p-crotonoylaminophenoxyacetic acids in the presence of gentamycin, water-soluble polymer salts containing from 10 to 25 mass% of gentamycin were obtained. These salts regardless of gentamycin content completely retain high level of antimicrobial activity of gentamycin against Staphylococcus spp. and Escherichia coli and are characterized by less (by more than one order of magnitude) acute toxicity.

[The chronological structure of the population count of the taiga tick in the Maritime Territory]. / Khronologicheskaia struktura chislennosti taezhnogo kleshcha v Primorskom krae.

A time series analysis of 23-years observations of the Ixodes persulcatus imago dynamics was carried out. The tick were counted in forests of the western Sikhote-Alin' foothills near Ussuriysk. The fluctuations of the ticks number are quasiperiodical. They are formed by near 3-years oscillations, long-term non linear trend and accidental component. The observed process was described by means of a statistic model. This model combines the harmonic regression analysis with linear regression analysis. The determination coefficients are 90.8% and 92.7% for the descriptive and prognostic models respectively. The difference between two groups of environmental factors, which influence on the tick number, is discussed. These factors are: 1) the directly influencing factors (functional factors), 2) the factors influencing by dint of natural rhythms being general for a biocoenosis (synchronizing factors).

IgG avidity assay for estimation of the time after onset of hantavirus infection in colonized and wild bank voles.

An immunoglobulin G avidity assay was used to determine recent and past hantavirus infection in bank voles (Clethrionomys glareolus). Sera of experimentally infected bank voles were studied at different time intervals. The avidity of specific IgG increased over time after infection. This experimental data were used to estimate the time after onset of hantavirus infection in naturally infected bank voles caught in an endemic area. The possibility to discriminate between recently infected animals and animals infected some time ago is important since the proportion of recently infected bank voles represents the intensity of the epizootic which in turn correlates to the risk of humans to contract the disease.

[The location of the infecting tick bite and the severity of the course of tick-borne encephalitis]. / Lokalizatsiia zarazhaiushchego ukusa kleshcha i tiazhest' techeniia kleshchevogo éntsefalita.

Analysis of 846 epidemiological charts of unvaccinated tick-borne encephalitis patients in the period of 1956-1985 established that in 21% cases the disease resulted from multiple bites of the ticks, in 67.3% it occurred from single bites. In 11.7% of the patients, the bite was denied. Single infecting bites were mostly those of the head and neck (39.2% cases), especially frequent among children (84.9%). The upper part of the body and hands were bitten less frequently (16.7 and 12.5%, respectively). Other sites of the bite were reported in 6-10%. The most complicated pattern of tick-borne encephalitis is observed in case of multiple bites: two-fold increase in mortality rates compared to single bites (23.2 vs. 10.7%) and higher percent of focal forms (72.7 vs. 56.5%). In case of the single bites a certain correlation is observed between the site of the bite and the outcome of the disease: fatal outcomes are most frequent in case of the bites in the axilla, arms (14-16%), head and neck (11.2%), and less frequent in case of the bites in the lower limbs (5.9%) and groin (0). The nature of the infecting bite determines, to a great extent, the pathogenesis and outcome of the disease. The prevention of multiple bites would help considerably to reduce mortality rates.

[Correlations of the indices of tick-borne encephalitis morbidity in the Maritime Territory with natural factors]. / Korreliativnye sviazi pokazatelei zabolevaemosti kleshchevym éntsefalitom v Primorskom krae s nekotorymi prirodnymi faktorami.

The comparison of the absolute figures of the tick-borne encephalitis morbidity and mortality rates in the Primorye Territory for 16-22 years with the climatic parameters and the characteristics of the natural focus in the key area has allowed one to reveal close relationship between the two above-mentioned epidemiological characteristics and such factors as the intensity of monsoon rains and the size of the population of large-toothed redback voles in the previous year. Multiple regression equations suitable for the prognosis of the morbidity and mortality levels in the territory for the coming year have been set up.