Studies of ticks of the genus Dermacentor (Acari; Ixodidae) on the natural occurrence of tularemia pathogen in the conditions of the Central Pre-Caucasian region

The purpose of the research is the assessment of the Francisella tularensis occurrence in nature in ticks of the genus Dermacentor; understanding the physiological age in terms of tick infection with tularemia pathogen.Materials and methods. For the period from 2015 to 2019, we examined 8449 specimens of Dermacentor marginatus (916 pools), 8674 specimens of D. reticulatus (705 pools), and 109 specimens of D. niveus (40 pools) for tularemia infection. To assess the dependence of tularemia pathogen found in ticks of different physiological ages, we examined 2440 specimens of D. marginatus (360 pools), and 3349 specimens of D. reticulatus (412 pools) for the period from 2016 to 2019. Studies of ixodid ticks infected with tularemia pathogen were performed by the Natural Focal Infection Laboratory of the Stavropol Anti-Plague Institute. Pools of ixodid ticks were examined for the pathogen DNA of tularemia using reagent kits for identifying Francisella tularensis DNA by polymerase chain reaction with fluorescence hybridization of results recorded in real time.Results and discussion. The infection rate of the tularemia pathogen in ticks in the Central Pre-Caucasian region ranged from 0.044–1.127% in D. marginatus and 0.035–1.455% in D. reticulatus in different years. The greatest number of F. tularensis was isolated from the III physiological age ticks. For D. reticulatus ticks, no statistically significant dependence of the detected tularemia pathogen on physiological age was found.

ON STUDY OF BOVINE PYROPLASMOSIS IN THE LOWLAND AND FOOTHILL ZONES OF ARMENIA

In two landscape zones of the Republic of Armenia, the regularities of the course of one of the most common haemosporidiosis in cattle, piroplasmosis, were studied. Based on our research, a difference was established in the timing of the onset of the disease, the number of outbreaks, and the severity of clinical signs in animals of the lowland and foothill zones. We have proved that 4 outbreaks of the disease took place in the farms of the lowland zone: the first at the end of April after the attack of ticks on the animal. At the same time, the first symptoms of the disease were noted. The second outbreak of the disease and a high degree of ticks were recorded in the second half of July. The third outbreak was in early August and the fourth in autumn starting from the 10th of October. In contrast to the lowland, there were 3 outbreaks of piroplasmosis in the farms of the foothill zone, and they were not very pronounced. This phenomenon can be explained by the difference in the temperature regime of the natural habitat. In the lowland zone, 4 species of ticks were recorded with the dominant species being Boophilus annulatus rarely found in the foothill zone. In the foothill zone, the same species of ticks as in the lowland were identified, along with the species Dermacentor marginatus.

Geographical and Tick-Dependent Distribution of Flavi-Like Alongshan and Yanggou Tick Viruses in Russia

The genus Flavivirus includes related, unclassified segmented flavi-like viruses, two segments of which have homology with flavivirus RNA-dependent RNA polymerase NS5 and RNA helicase-protease NS3. This group includes such viruses as Jingmen tick virus, Alongshan virus, Yanggou tick virus and others. We detected the Yanggou tick virus in Dermacentor nuttalli and Dermacentor marginatus ticks in two neighbouring regions of Russia. The virus prevalence ranged from 0.5% to 8.0%. We detected RNA of the Alongshan virus in 44 individuals or pools of various tick species in eight regions of Russia. The virus prevalence ranged from 0.6% to 7.8%. We demonstrated the successful replication of the Yanggou tick virus and Alongshan virus in IRE/CTVM19 and HAE/CTVM8 tick cell lines without a cytopathic effect. According to the phylogenetic analysis, we divided the Alongshan virus into two groups: an Ixodes persulcatus group and an Ixodes ricinus group. In addition, the I. persulcatus group can be divided into European and Asian subgroups. We found amino acid signatures specific to the I. ricinus and I. persulcatus groups and also distinguished between the European and Asian subgroups of the I. persulcatus group.

Оценка иммуногенности экспериментального образца адсорбированной инактивированной культурально-клеточной вакцины против анаплазмоза овец

Анаплазмоз овец – кровепаразитарная трансмиссивная болезнь, вызываемая эндоглобулярным внутриэритроцитарным паразитом Anaplasma ovis Lestoguard, 1924 (порядок Rickettsiales, семейство Anaplasmataceae). Основные признаки анаплазмоза – анемия, исхудание, потеря продуктивности и нарушение воспроизводительной функции животных. Анаплазмоз наносит овцеводству значительный экономический ущерб. Основная эпизоотическая роль в распространении анаплазмоза овец принадлежит клещу Dermacentor marginatus. Этот вид клеща развивается по треххозяинному типу. Весной, с первых дней выхода животных на пастбище, D. marginatus нападает на них в стадии имаго. Прокормителями юных стадий клеща служат мелкие грызуны: мыши, суслики, хомяки и др. В июне–июле клещ не активен. В третьей декаде августа и до конца октября нападение на скот возобновляется [2]. Поэтому изыскание мер профилактики анаплазмоза овец, а именно создание вакцины, является актуальным.

Genetic Diversity of Hard Ticks (Acari: Ixodidae) in the South and East Regions of Kazakhstan and Northwestern China

To date, there is no report on the genetic diversity of ticks in these regions. A total of 370 representative ticks from the south and east regions of Kazakhstan (SERK) and Xinjiang Uygur Autonomous Region (XUAR) were selected for molecular comparison. A fragment of the mitochondrial cytochrome c oxidase subunit I (cox1) gene, ranging from 631 bp to 889 bp, was used to analyze genetic diversity among these ticks. Phylogenetic analyses indicated 7 tick species including Hyalomma asiaticum, Hyalomma detritum, Hyalomma anatolicum, Dermacentor marginatus, Rhipicephalus sanguineus, Rhipicephalus turanicus and Haemaphysalis erinacei from the SERK clustered together with conspecific ticks from the XUAR. The network diagram of haplotypes showed that i) Hy. asiaticum from Almaty and Kyzylorda Oblasts together with that from Yuli County of XUAR constituted haplogroup H-2, and the lineage from Chimkent City of South Kazakhstan was newly evolved; and ii) the R. turanicus ticks sampled in Israel, Almaty, South Kazakhstan, Usu City, Ulugqat and Baicheng Counties of XUAR were derivated from an old lineage in Alataw City of XUAR. These findings indicate that: i) Hy. asiaticum, R. turanicus and Ha. erinacei shared genetic similarities between the SERK and XUAR; and ii) Hy. marginatum and D. reticulatus show differences in their evolution.

Lumpy skin disease in Kazakhstan

This study describes the registration of the first cases of lumpy skin disease in July 2016 in the Republic of Kazakhstan. In the rural district of Makash, Kurmangazinsky district of Atyrau region, 459 cattle fell ill and 34 died (morbidity 12.9% and mortality 0.96%). To determine the cause of the disease, samples were taken from sick and dead animals, as well as from insects and ticks. LSDV DNA was detected by PCR in all samples from dead animals and ticks (Dermacentor marginatus and Hyalomma asiaticum), in 14.29% of samples from horseflies (Tabanus bromius), and in one of the samples from two Stomoxys calcitrans flies. The reproductive LSD virus was isolated from organs of dead cattle and insects in the culture of LT and MDBK cells. The virus accumulated in cell cultures of LT and MDBK at the level of the third passage with titers in the range of 5.5–5.75 log 10 TCID50/cm3. Sequencing of the GPCR gene allowed us to identify this virus as a lumpy skin disease virus.

Identity and microbial agents related to Dermacentor marginatus Sulzer (Acari: Ixodidae) with a new record of Rickettsia slovaca (Rickettsiales: Rickettsiaceae) in Iran

Dermacentor marginatus is a known vector of Rickettsia slovaca and Anaplasma ovis distributed across Eurasia. A total of 300 D. marginatus adult male ticks were collected, removed from sheep in East Azerbaijan province, northwestern Iran. The DNA of Rickettsia and Anaplasma were found in 10 (two pools) ticks by PCR amplifying parts of ompA and msp4 genes, respectively. Our study describes the first PCR detection of tick-borne pathogens, R. slovaca and A. ovis, show that they are spread in D. marginatus of Iran highlight their risk for human and animal hosts. Different patterns (ornamentation) were observed. The identity of different patterns in this study was evaluated with cytb, 16S rRNA and ITS2 genes. BLAST analysis of the cytb, 16S rRNA, ITS2 nucleotide sequence was showed 99%, 98%–100% and 98% sequence identity to sequences of D. marginatus, respectively. It was found that all different patterns of this study are in fact a polymorphic species, D. marginatus. These data increase our knowledge of tick and tick-borne microbial agents in Iran.

Scalp eschar and neck lymphadenopathy by Rickettsia slovaca after Dermacentor marginatus tick bite case report: multidisciplinary approach to a tick-borne disease

Background Scalp Eschar and Neck LymphAdenopathy after Tick bite is a zoonotic non-pathogen-specific disease most commonly due to Rickettsia slovaca and Rickettsia raoultii. Diagnosis is mostly based only on epidemiological and clinical findings, without serological or molecular corroboration. We presented a clinical case in which diagnosis was supported by entomological identification and by R. slovaca DNA amplifications from the tick vector. Case presentation A 6-year-old child presented with asthenia, scalp eschar and supraclavicular and lateral-cervical lymphadenopathy. Scalp Eschar and Neck LymphAdenopathy After Tick bite syndrome following a Dermacentor marginatus bite was diagnosed. Serological test on serum revealed an IgG titer of 1:1024 against spotted fever group rickettsiae, polymerase chain reaction assays on tick identified Rickettsia slovaca. Patient was successfully treated with doxycycline for 10 days. Conclusions A multidisciplinary approach including epidemiological information, clinical evaluations, entomological identification and molecular investigations on tick, enabled proper diagnosis and therapy.

Etiopathogenetic Assessment of Tick Skin Injuries in Vacationers of Suburban Resorts and Tourists of Ukraine as a Component of a Complex Diagnostic Algorithm of Babesiosis

Aim: The aim of the study is to improve the complex diagnostic algorithm of babesiosis by etiopathogenetic assessment of tick skin lesions in vacationers of suburban resorts and tourists of Ukraine. Material and Methods: In order to objectify the etiopathogenetic assessment of tick skin lesions in vacationers of suburban resorts and tourists of Ukraine, animals affected by attacks of active stages of Ixodes, to determine their role as a component in a comprehensive diagnostic algorithm of babesiosis, we used a set of epidemic, epizootological, clinical and diagnostic measures. Skin lesions were considered acaroidal only in cases when ticks from the superfamily Ixodoidea of the family Ixodidea of the species Ixodes ricinus and Ixodes persulcatus (n=34), Dermacentor marginatus and Dermacentor pictus (n=128) were detected on it or on the clothes of the bitten person. Ticks of the species Ixodes ricinus, Ixodes persulcatus, Dermacentor marginatus and Dermacentor pictus were studied and photographed on an Olympus BX-41 microscope (Japan) using a digital camera. The surveyed 64 people of both sexes, aged 17 to 68, belonged to different categories of vacationers or tourists (organized, semi-organized, «savages»). The morphological material (skin with underlying soft tissues) was collected in cases of attacks of Ixodes on pets (dogs), accompanying the owners on vacation, when it was possible. Microspecimens stained with hematoxylin and eosin, picrofuxin according to van Gizon, according to Mallory were studied using an Olympus BX-41 microscope (Japan) with subsequent processing with the Olympus DP-soft version 3.1 software. Results: Climatotherapy is a popular treatment and prevention measure in the coordinate system «doctor-patient». This treatment method is characterized by both positive health effects and negative consequences, among which are the development of such dangerous parasitic disease as babesiosis. Etiopathogenetic assessment of tick skin lesions in vacationers of suburban resorts and tourists of Ukraine is an important component of a comprehensive diagnostic algorithm for babesiosis. Its objectification is based on the effective application of the data informative potential on the cycle and period of development of one generation of carriers (imago), the specifics of active stages (differentiation into three-host mites), habitat characteristics (shrubs, deciduous trees), seasonality (April-June, August-September), climatic zonation (temperate climate of the forest-steppe), their ability to inoculate babesiosis pathogens into the body of warm-blooded vertebrates. Macroscopic and microscopic features of the skin with underlying soft tissues at the sites of fixation and feeding of mites in susceptible to pathogens babesiosis humans and animals depend on the duration of this damaging factor exposure. Conclusions: Etiopathogenetic assessment of tick skin lesions in vacationers of suburban resorts and tourists of Ukraine is of great importance in the diagnosis of babesiosis.