[Genetic identification of rickettsiae of the tick-borne spotted fever group, isolated in the foci of tick-borne rickettsiosis]. / Geneticheskaia identifikatsiia rikketsii gruppy kleshchevoi piatnistoi likhoradki, izolirovannykh v ochagakh kleshchevogo rikketsioza.

A total of 25 rickettsial cultures of the tick-borne spotted fever (TBSF) group from the collection of the Research Institute of Infections in Omsk, isolated from different sources in the territory of the Russian Federation (from the Urals to the Far East) during the period of 1954-2001) were studied by the methods of genetic analysis. The fragments of the gene coding the outer-membrane protein of 190 kD (ompA) and synthetase citrate (gltA) of the rickettsiae under the study were sequenced. 23 isolates were identified as R. sibirica, among them 3 isolates obtained from patients, 16 isolates obtained from Dermacentor ticks, 2 isolates from Haemaphysalis concinna and 2--from Ixodes persulcatus. The strain Primorye 32/84, isolated from D. silvarum ticks in the Far East and earlier identified as S. sibirica by the results of the PCR-RFLP analysis proved to be a genovariant Rickettsia spBJ-90, i.e. close to this species. Strain Karpunino 19/69, isolated in the Kurgan region, was identified as R. slovaca. The results obtained extended our notions of the spectrum of rickettsiae group TBSF in Russia as well as their vectors.

[Epidemiology of Ixodes tick-borne borreliosis in the north of the Volga-Viatka region]. / Epidemiologiia iksodovogo kleshchevogo borrelioza na severe Volgo-Viatskogo regiona.

Among the territories of the Volga-Vyatka Region of Russia, the Kirov Region is characterized by the highest incidence of Ixodes tick-borne borreliosis. Its incidence rates ranged from 10.5 to 48.6 per 100,000 inhabitants. The average long-term regional rate was 8 times as high as the federal one. The bulk of cases was notified in the central regional districts referred to as a southern taiga subarea. The infection with the borreliae I. persulcatus and I. ricinus was 21-29%. Urban inhabitants infected for domestic reasons were prevalent among those who had been ill. Patients aged above 40 years accounted for 64.5%. There was an increase in the proportion of patients referring for medical care for the bites being stuck. Cases of mixed infections (Ixodes tick-borne borreliosis and tick-borne encephalitis) came to be more frequently detected; these constituted about a third of all tick-borne infections.

[New evidence for the detection of ehrlichia and anaplasma in ixodes ticks in Russia and Kazakhstan]. / Novye dannye o vyiavlenii érlikhii i anaplazm v iksodovykh kleshchakh v Rossii i Kazakhstane.

Polymerase chain reaction and sequence analysis were used to screen Ehrlichia and Anaplasma DNA in 900 specimens of Ixodes ticks of four genera (Dermacetor, Haemaphysalis, Ixodes, and Hyalomma) collected on 14 administrative territories of Russia and Kazakhstan. Anaplasma phagocytophilia DNA was detected and identified in Ixodes persulcatus ticks gathered in the Altai and Primorye Territories. Ehrlichia muris DNA was genotyped in the I. persulcatus ticks collected in the Tyumen, Omsk, and Novosibirsk Regions and the Altai Territory. Examining the Haemaphysalis concinna collected in the Primorye Territory revealed A. bovis DNA. The I. persulcatus ticks gathered in the Omsk Region were found to have "Ehrlichia-like "Schotti variant" DNA, Studying the ticks of the genera Dermatocentor and Hyalomma gathered in Russia and Kazakhstan failed to detect the representatives of the genera Anaplasma and Ehrlichia. The detection of A. phagocytophilia DNA in the I. persulcatus ticks in the Altai and Primorye territories and the serological verification of cases of human granulocytic anaplasmosis among patients with tick-borne infections in these territories lead to the conclusion that there are natural loci of this disease in West Siberia and the Far East of Russia.

[Detection of Rickettsia hulinii in ticks of the Haemaphysalis concinna species in Russia]. / Obnaruzhenie Rickettsia hulini v kleshchakh Haemaphysalis concinna na territorii Rossii.

The presence of Rickettsia hulinii was detected in ticks of the Haemaphysalis concinna species in the Asiatic part of Russia. It was the first detection of these rickettsiae outside the territory of the Chinese People's Republic. This tick is spread over a broken area and may occur in different regions of Eurasia. At present at least 3 rickettsial species of the tick-borne spotted fever group were found in Ixodes ticks on the territory of Eastern Siberia: R. sibirica, known to be the etiological agent of tick-borne rickettsiosis, R. hulinii with proved pathogenicity for laboratory animals and R.DnS14 with no data available on its pathogenicity.

[Epidemiology of hemorrhagic fever with renal syndrome in the north Volga-Viatka region]. / Epidemiologiia gemorragicheskoi likhoradki s pochechnym sindromom na severe Volgo-Viatskogo regiona.

The results of the ecological and epidemiological study of hemorrhagic fever with the renal syndrome (HFRS) in the Kirov region for the period of 1987-2000 are presented. HFRS morbidity rate varied from 1.3 to 13.7 per 100,000 population, which corresponded to the figures registered in the Volga Vyatka region. Cases of HRFS were mainly (90%) registered in three southern districts of the region. The moderate degree of correlation between morbidity rate and the number of wild mammals (r = 0.55) was established. Periodic morbidity rise occurred every 3 years. In 1998-2000 the contamination of wild mammals with HFRS virus increased and reached 7.6-9.5%. Infection factors connected with everyday human activities somewhat prevailed, industrial and agricultural types of infection constituting 43.8%. Males aged 20-49 years prevailed among the patients. Morbidity rate among urban dwellers exceeded that among town residents.

[Combined focus of tick-borne encephalitis, tick-borne rickettsiosis and tularemia in the habitat of Haemaphysalis concinna in south central Siberia]. / Sochetannyi ochag kleshchevogo éntsefalita, kleshchevogo rikketsioza i tuliaremii v areale kleshchei Haemaphysalis concinna na ioge tsentral'noi Sibiri.

For the first time in the Krasnoyarsk region the population Haemaphysalis concinna ticks were found to be infected with the causative agents of three natural focal tick-borne infections--tick-borne encephalitis, tick-borne rickettsiosis and tularemia. The existence of the combined natural focus of these three infections has been confirmed by epidemiological data. Ticks Dermacentor nuttalli also play a similar role in combined foci of tick-borne encephalitis and tick-borne rickettsiosis in these focal territories.

[Data on the typing of natural foci of tick-borne rickettsiosis in Siberia and the Far East]. / Materialy po tipizatsii prirodnykh ochagov kleshchevogo rikketsioza Sibiri i Dal'nego Vostoka.

The studies of the level of Ixodidae ticks infestation and seroepidemiological parameters made it possible to characterize specific features of the epidemic process in foci with different tick species. A working principle for the typing of the natural foci of tick-borne rickettsiosis has been suggested. According to the number of tick species 3 types of foci have been identified: monovector, divector and polyvector foci.

[New findings concerning the spread of natural foci of infection in the transpolar region of eastern Siberia]. / Novye dannye o rasprostranenii prirodnoochagovykh infektsii v Zapoliar'e Vostochnoi Sibiri

New materials are presented on the presence of the foci of anthropozoonozes in the Extreme North. For the first time there was established the existence in the subarctic tundra of the Taimyr peninsula of the arbovirus foci of the tick-borne encephalitis complex. A virus of the tick-borne encephalitis complex was isolated in 1973 from the gamasida ticks Haemogamasus ambulans Thorel. and Hirstionyssus isabellinus Oudms. and the nests of the Siberian lemming Lemmus lemmus L. This pointed to the existence in the Transpolar region of the foci or arboviruses in the nest-hole biocenoses of the lemmings outside the bird colonies. Cultures of tularemia bacilli (which proved the etiology of the epizootic among the lemmings observed in 1973 and also the presence of the lemming natural foci of tularemia and their combination with the arbovirus foci) were isolated from the lemmings at the same territory. The results of serological examination of the local population and of the animals pointed to the circulation in the Transpolar region of the causative agents of leptospirosis, toxoplasmosis, Q-fever and of the Asian tick-borne rickettsiosis.