Acaricide Treatments Research Articles

Optimizing long-acting acaricide use for integrated tick management of Rhipicephalus australis-infesting cattle in New Caledonia.

The tick Rhipicephalus australis, formerly known as Rhipicephalus microplus, is the most economically important ectoparasite of livestock in New Caledonia, affecting cattle health and production. Decades of control attempts based on the application of chemical acaricides have exerted a strong selective pressure on R. australis populations, some of which have evolved resistance to these treatments. Research to develop integrated tick control programs is now focused on decreasing applications of chemicals. This study reports the implementation of a method of pasture and herd management involving minimal strategic use of long-acting acaricides, here defined as those having substantial efficacy against larvae for several weeks. Diverse parameters concerning the utilization of long-acting acaricides in association with pasture and herd management on 21 New Caledonian farms over a 5-year period were analyzed to optimize their strategic use. Longer larval acaricidal effect was achieved with a commercial pour-on formulation of fluazuron than with a commercial injectable (subcutaneous) formulation containing 3.15% ivermectin. Pasture and herd management allowed an increase in the delay between a long-lasting acaricide application and the subsequent acaricide treatment from 11.0weeks to 17.7weeks. However, if ticks were detected and reported by producers on the day of a long-acting acaricide application, the delay to the following treatment was reduced from 18.5weeks to 11.2weeks. The impact of a long-acting acaricide treatment on larval populations in pastures was greatest with a stocking rate of 5 animals per hectare grazing during 1week. These results provide science-based evidence to cattle producers for adaptive integrated tick management in order to delay the development of acaricide resistance.

Africanized honey bees in Colombia exhibit high prevalence but low level of infestation of Varroa mites and low prevalence of pathogenic viruses.

The global spread of the ectoparasitic mite Varroa destructor has promoted the spread and virulence of highly infectious honey bee viruses. This phenomenon is considered the leading cause for the increased number of colony losses experienced by the mite-susceptible European honey bee populations in the Northern hemisphere. Most of the honey bee populations in Central and South America are Africanized honey bees (AHBs), which are considered more resistant to Varroa compared to European honey bees. However, the relationship between Varroa levels and the spread of honey bee viruses in AHBs remains unknown. In this study, we determined Varroa prevalence and infestation levels as well as the prevalence of seven major honey bee viruses in AHBs from three regions of Colombia. We found that although Varroa exhibited high prevalence (92%), its infestation levels were low (4.5%) considering that these populations never received acaricide treatments. We also detected four viruses in the three regions analyzed, but all colonies were asymptomatic, and virus prevalence was considerably lower than those found in other countries with higher rates of mite-associated colony loss (DWV 19.88%, BQCV 17.39%, SBV 23.4%, ABPV 10.56%). Our findings indicate that AHBs possess a natural resistance to Varroa that does not prevent the spread of this parasite among their population, but restrains mite population growth and suppresses the prevalence and pathogenicity of mite-associated viruses.

First tick and tick damage perception survey among sedentary and transhumant pastoralists in Burkina Faso and Benin.

BackgroundTranshumance, a main ancestral animal production strategy of the West African Countries (WAC), can favour the spread of vectors and vector‐borne diseases within and/or across countries. Transhumance has been implicated in such spread as well as that of related tick‐borne diseases (TBD).Methods and principal findingsUsing a questionnaire survey and statistical modelling, this study explores the perception of herders about ticks and TBD in cattle, their practices in tick control and the social groups involved in cattle farming in eastern Burkina Faso (46 random herds) and in the northern Benin (44 random herds). Results show that most of the herders (79%) are from the Fulani social group. The principal and secondary activities of herders are respectively cattle farming and agriculture. The mean age of pastoralists is between 40 and 50 years depending on the province of origin and 60% of the surveyed herds practice internal or transboundary transhumance. Herders have a clear knowledge of different genus of ticks except the genus Rhipicephalus. Their knowledge of TBD is very limited. These results also reveal that herders in Benin use less acaricides treatment calendar compared with those in Burkina Faso. Transhumant pastoralists (i.e. transhumant cattle farmers) plan more acaricide treatment and have more cows with lost teats (i.e. tick damage) than the sedentary ones. In addition, amitraz appears to be the main acaricide compound used by herders for tick control (68%) but its use is inappropriate and its source is frequently the unregulated market.Conclusions and significanceAll of these findings can induce acaricide resistance especially as the inefficacy of amitraz against Rhipicephalus (Boophilus) microplus has already been reported in previous studies. Such results would help to elaborate suitable strategies of control and prevention of ticks and TBD in Burkina Faso and Benin.

Effect of Anti-acaricide Treatment on Tick Species Present and Performance of Growing Beef Heifers

Abstract The Edwards Plateau region of Texas is largely used for grazing cattle and small ruminants. Tick parasitism in range livestock can occur year-round with direct production losses manifested as body weight or condition. The objective was to assess two acaricide treatments on the active tick burden on livestock within two forage growing seasons (winter through summer). At the Sonora AgriLife Station, 22 Bos taurus crossbred heifers (248 ± 47 kg) were maintained on 97 hectares of rangeland. Tick burden was assessed by individual animal inspection every two wk from 18-Dec-2019 to 11-May-2020 (Season 1) and from 8-Jun-2020 to 3-Aug-2020 (Season 2). Acaricide treatment was applied each date to heifers chosen randomly to serve in the non-treated control (control: 11 heifers) or acaricide-treated (treatment: 11 heifers) groups. Season 1 acaricide treatment was a pour-on synthetic pyrethroid (11 dates) and Season 2 was a diluted synthetic pyrethroid whole-body spray (5 dates). Tick species observed included Amblyomma americanum and Dermacentor albipictus. Tick burden (total counts) and body condition score differences were determined by analysis of variance procedures. For tick burden, there were significant differences (P < 0.0012) between treatment (0.528 ± 0.06) and control (0.819 ± 0.06) heifers in Season 1 (0.673 ± 10.44), and no differences (P > 0.11) between treatment (0.642 ± 0.07) and control (0.799 ± 0.07) heifers in Season 2 (0.721 ± 2.64). For body condition score, there were no differences (P > 0.72) between treatment (5.61 ± 0.04) and control (5.59 ± 0.04) heifers in Season 1 nor Season 2 (5.51 ± 0.005 and 5.80 ± 0.47, respectively). Season 1 acaricide treatment was effective in controlling tick burden (efficacy = 3–4 wk) as compared to Season 2 (efficacy = 1–2 wk). Tick burdens observed under the conditions of this study had no effect on body condition.

Trends in Epidemic Process Development of Tick-Borne Encephalitis in the Russian Federation, Laboratory Diagnosis, Prophylaxis and Forecast for 2021

Tick-borne encephalitis is a natural-focal infection damaging central nervous system, caused by the similarly-named virus transmitted by several species of ixodic ticks. Natural foci of tick-borne encephalitis (TBE) are widely spread in the forest and forest-steppe landscape zones of the temperate climate belt in the vast territory of Eurasia from the Atlantic to the Pacific Ocean. New TBE-endemic territories have been recently identified in Japan, the Netherlands, and in the UK – in 2019. The increasing risk of infection due to the development of tourism and visits to natural foci of TBE became a public health issue of international concern. The aim of the study is to identify modern features of TBE incidence dynamics in the Russian Federation, the state of laboratory diagnostics and prevention and to predict the incidence for 2021. The paper shows that there is a persistent downward trend in TBE-cases in Russia, which is observed through the past few years. The characteristic feature of the epidemic season-2020 was a significant reduction in the incidence of TBE: 989 cases were registered in 33 constituent entities of the Russian Federation (morbidity rate – 0.67 per 100 000 of the population). The sharp decrease of TBE cases in 2020 as compared to 2019 against the background of a decrease in vaccination can be explained, along with natural factors, by the introduction of restrictive measures during the COVID-19 epidemic. The paper also reflects the dynamics of morbidity, seeking the medical services because of tick bites, the infection rate of the carrier, the scope of vaccination, seroprophylaxis, acaricide treatments. The coverage of express-diagnostic tests of ticks for markers of associated pathogens and its availability for the population are presented. It is recognized that the epidemiological situation on TBE in the Russian Federation remains unfavorable. It demands constant attention on the part of healthcare organizations and Federal Service for Surveillance in the Sphere of Consumers Rights Protection and Human Welfare, as well as management decision making aimed at further decrement in TBE incidence through the improvement of prevention measures, specifically in the entities that are characterized by high TBE incidence. The situation requires monitoring of natural foci of infection, enhancement of prophylaxis and treatment of TBE. The paper provides the forecast of TBE incidence for 2021 and values of the 95 % confidence range of the indicator fluctuation, taking into account the presence or absence of trends in its changes in the territory of federal districts and constituent entities of the Russian Federation in 2011–2020.

Method for detection latent natural foci of wild animals babesioses in nature conservation reserves

Babesioses are large group of natural focus transmissive tick-born diseases, which are wide spread and damage many species of domestic and wild animals. Babesia spp. the causative agents of babesiosis in livestock also infect the phylogenetic species of wild animals. Vectors of Babesia spp are hard ticks. In agriculture for control of tick the insectoacaricides are used usually. But this way is impossible for nature conservation reserves because the employment of chemical and biological drugs for acaricidal treatment is prohibited by Federal Low N 33 from 14.03.95. The purpose of the manuscript is providing the methodology for detection of natural foci of animal babesiosis for evaluation of epizootological situation in nature conservation reserves. The Method is based on Babesia lifecycle and observation of Babesia in tissues ang egg of ticks.

Molecular prevalence, characterization and associated risk factors of Anaplasma spp. and Theileria spp. in small ruminants in Northern Pakistan.

This study was conducted in four districts (Malakand, Swat, Bajaur and Shangla) of Northern Pakistan to investigate the prevalence, associated risk factors and phylogenetic analyses of Theileria and Anaplasma species in small ruminants. A total of 800 blood samples, 200 from each district, were collected from apparently healthy animals. PCR assays were performed using generic primers for Anaplasma spp. and Theileria spp. as well as species specific primers for A. ovis and T. ovis. Overall infection prevalence was 361/800 (45.1%). Theileria spp. infection prevalence (187/800, 23.3%) was higher than Anaplasma spp. (174/800, 21.7%). Amplified partial 18S rRNA genes were sequenced and enrolled animals were found to be infected by T. ovis (115/800, 14.3%), and at least two more Theileria species (72/800, 9%) were present (T. lestoquardi and T. annulata). All blood samples that were found to be positive for Anaplasma spp. were also positive for A. ovis. Infection prevalence was higher in sheep (227/361, 28.3%) compared to goats (134/361, 16.6%) (p < 0.005). Univariable analysis of risk factors showed that host, age, grazing system and acaricide treatment were significant determinants (p < 0.05) for both Theileria and Anaplasma infections. Multivariable analysis revealed that host, sex, age, tick infestation and grazing system were significant risk factors (p < 0.005) for both pathogens. Phylogenetic analysis revealed variants among the A. ovis and T. annulata samples analysed, indicating that different genotypes are circulating in the field while T. ovis presented the same genotype for the samples analysed.

Оценка эпидемической ситуации по заболеваемости клещевым риккетсиозом и клещевым энцефалитом населения Алтайского края в 2000-2019 гг.

The article presents the results of a study carried out in relation to the epidemic situation in terms of the incidence of one of the topical representatives of tick-borne natural focal infections among the population of the Altai Territory in the period from 2000 to 2019 – tick-borne rickettsiosis and tick-borne encephalitis. An assessment of the prevalence of these infections among certain age and social groups of the region's population is presented. Using GIS technologies and the method of sigma deviations, the spatial prevalence of current infections in the territory of the region was estimated and regions with high, medium and low, for the Altai Territory, incidence of tick-borne encephalitis and tick-borne rickettsiosis during the study period were identified. The results of the assessment of preventive measures carried out in the region aimed at reducing the incidence of current infections among the local population – vaccine prophylaxis, seroprophylaxis and acaricidal treatments of territories are presented.

Transient Threshold Abundance of Haematobia irritans (Linnaeus, 1758) In Cattle Under Integrated Farming Systems

Haematobia irritans is a hematophagous insect that affects the welfare of cattle reducing weight gain and it is present in most countries. The objective of this work was to determine the prevalence of flies, mainly H. irritans in 36 Red Angus calves under four farming ecosystems in Brazil, and to assess an individual threshold limit to treat for horn fly and to attain better animal welfare and farm sustainability. The animals (n = 9) were allocated in livestock (L), crop-livestock (CL), livestock-forestry (LF) and the full integration of crop-livestock-forestry (CLF) conditions. Adult flies were determined between systems on each animal at weekly intervals and in each environment by counting larvae and pupal stages that emerged from selected dung pads. Individual animals were treated for H. irritans infestation after reaching the transient threshold abundance (TTA) of > 100 flies. The data from 1008 evaluations showed that animals in the CLF had significantly (P < 0.05) more horn flies, than animals from the other systems. The level of infestation by horn flies was strongly influenced by the particular ecosystem (P < 0.002), and by the month of the year (P < 0.001). However, the difference in fly numbers did not influence the weight gain of the animals. We found four other genera of the Diptera order (Brontaea spp., Cyrtoneuropsis spp., Fannia spp. and Morellia spp.) that emerged from dung pads. The data suggests that it may be possible to perform evaluations in one animal at a time to control H. irritans with no impact to the performance of the animals when using a low TTA index of infestation. CLF was considered to be the richest environment, favoring fly populations. In our conditions, cattle and different fly species/genera may coexist using sustainable TTA management protocols at farm level in opposite to the concept of fly eradication or mass acaricidal treatment.

Geographical Distribution and Selection of European Honey Bees Resistant to Varroa destructor.

Simple SummaryThe parasitic mite Varroa destructor is a major challenge to honey bee populations worldwide. Some honey bee populations are resistant to the mite, but most of the commercially used stocks are not and rely on chemical treatment. In this article, we describe known varroa-resistant populations and the mechanisms which have been identified as responsible for survival of colonies without beekeeper intervention to control the mite. We review traits that have potential in breeding programs, discuss the role played by V. destructor as a vector for virus infections, and the changes in mite and virus virulence which could play a role in colony resistance. We also describe results of surveys carried out (mostly within Europe) on the presence of naturally surviving honey bee populations, on the commercial availability of mite resistant stock and on the traits considered in breeding programs. We found that there is a growing interest and awareness among beekeepers, but that there are very few commercially available resistant lines; some from breeding programs and some from naturally selected populations. The most commonly considered traits for assessing varroa resistance are linked to mite reproduction and specific hygienic behavior of the bees. Developing resistance to the varroa mite in honey bees is a major goal for apicultural science and practice, the development of selection strategies and the availability of resistant stock. Here we present an extended literature review and survey of resistant populations and selection programs in the EU and elsewhere, including expert interviews. We illustrate the practical experiences of scientists, beekeepers, and breeders in search of resistant bees. We describe numerous resistant populations surviving without acaricide treatments, most of which developed under natural infestation pressure. Their common characteristics: reduced brood development; limited mite population growth; and low mite reproduction, may cause conflict with the interests of commercial beekeeping. Since environmental factors affect varroa mite resistance, particular honey bee strains must be evaluated under different local conditions and colony management. The resistance traits of grooming, hygienic behavior and mite reproduction, together with simple testing of mite population development and colony survival, are significant in recent selection programs. Advanced breeding techniques and genetic and physiological selection tools will be essential in the future. Despite huge demand, there is no well-established market for resistant stock in Europe. Moreover, reliable experience or experimental evidence regarding the resistance of stocks under different environmental and management conditions is still lacking.

Genetic markers for the resistance of honey bee to Varroa destructor.

In the mid-20th century, the first case of infection of European bees Apis mellifera L. with the ectoparasite mite Varroa destructor was recorded. The original host of this mite is the Asian bee Apis cerana. The mite V. destructor was widespread throughout Europe, North and South America, and Australia remained the only continent free from this parasite. Without acaricide treatment any honeybee colony dies within 1–4 years. The use of synthetic acaricides has not justified itself – they make beekeeping products unsuitable and mites develop resistance to them, which forces the use of even greater concentrations that can be toxic to the bees. Therefore, the only safe measure to combat the mite is the use of biological control methods. One of these methods is the selection of bee colonies with natural mite resistance. In this article we summarize publications devoted to the search for genetic markers associated with resistance to V. destructor. The first part discusses the basic mechanisms of bee resistance (Varroa sensitive hygienic behavior and grooming) and methods for their assessment. The second part focuses on research aimed at searching for loci and candidate genes associated with resistance to varroosis by mapping quantitative traits loci and genome-wide association studies. The third part summarizes studies of the transcriptome profile of Varroa resistant bees. The last part discusses the most likely candidate genes – potential markers for breeding Varroa resistant bees. Resistance to the mite is manifested in a variety of phenotypes and is under polygenic control. The establishing of gene pathways involved in resistance to Varroa will help create a methodological basis for the selection of Varroa resistant honeybee colonies.

Assessment of laying-bird welfare following acaricidal treatment of a commercial flock naturally infested with the poultry red mite (Dermanyssus gallinae).

The poultry red mite (PRM), Dermanyssus gallinae, a potential vector of pathogens to animals and humans, causes impaired bird welfare. A study investigated changes in behavioural variables, physiological biomarkers, and health parameters following acaricidal treatment of PRM infestation of laying hens on a commercial farm. Mite traps determined the challenge to 12,700 hens before and after drinking water administration of the acaricide, fluralaner (Exzolt®, 0.5 mg/kg; Weeks 0 and 1). Weekly daytime direct observations and night-time video recordings monitored bird behaviours from Weeks -6 through +6. Blood samples were collected from randomly-selected birds (Weeks -6, -1, and +6). Following treatment, mite count reductions (>99%) were statistically significant (P < 0.0001), as were night-time reductions in the percent of hens showing activity, preening, head scratching (all P < 0.0001), and head shaking (P = 0.0007). Significant daytime reductions were observed in preening and head scratching (both P < 0.0001), head shaking (P = 0.0389), severe feather pecking (P = 0.0002), and aggressive behaviour (P = 0.0165). Post-treatment, comb wounds were significantly reduced (P = 0.0127), and comb colour was significantly improved (P < 0.0001). Heterophil/lymphocyte ratio was significantly reduced at Weeks 1 and 6 (P = 0.0009 and P < 0.0001, respectively). At Week 6, blood corticosterone (P = 0.0041) and total oxidant status (P < 0.0001) were significantly reduced, and haemoglobin and mean corpuscular haemoglobin significantly increased (P < 0.0001). Farm production records indicated that those post-treatment improvements were accompanied by significant reductions in weekly mortality rate (P = 0.0169), and significant recovery in mean weekly egg weights (P < 0.0001) and laying rate (P < 0.0001). The improvements in behavioural variables, physiological biomarkers, and health parameters that were observed following the elimination of PRM on a commercial farm indicate that infestations can be a cause of reduced hen welfare.

Evaluation of a 'Preventative' Strategy to Manage Spider Mites on Almond.

Simple SummaryThe almond industry in California produces approximately 80% of the world’s supply and currently consists of roughly 0.45 million bearing and non-bearing hectares. Spider mite management is a component of annual arthropod management strategies on almond. Regularly, acaricides containing the active ingredient, abamectin, are applied in spring when mites are not yet present or well below a level which justifies treatment, in other words applied to prevent rather than treat existing populations. Although other acaricides are used, those containing the active ingredient, abamectin, accounted for 68% to 95% of spring (preventative) applications between 2005 and 2017. Although the strategy is widely employed in the almond industry, there are no published studies supporting the practice. Moreover, the strategy runs contrary to sustainable, integrated pest management practices by forgoing monitoring, reliance on spider mite natural enemies, and economic threshold levels. In this study, we conducted large field trials to evaluate the effectiveness of preventative acaricide applications. Results showed that farmers can forego a preventative strategy since spider mite densities typically remain well below damaging levels through the period critical for tree growth and nut yield. Also, results showed that such a heavy reliance on abamectin has led to a low to moderate level of resistance developing in some spider mite populations in the southern and mid San Joaquin Valley.Field experiments were conducted in two commercial almond orchards located in the southern San Joaquin Valley during 2016 and 2017 to evaluate a “preventative” strategy to manage spider mites. Pacific mite, Tetranychus pacificus McGregor, was identified as the only mite species infesting the experimental sites in both years. We monitored mites weekly in 3.6-hectare plots over approximately 21 weeks in 2016 and in 2017 using guidelines developed by the University of California. In late May, prior to the detection of mites, preventative acaricide treatments, abamectin, cyflumetofen, or etoxazole were applied to the experimental plots at a field rate. In 2016 and 2017, mite densities in all the treatments increased at early-July, peaked at mid-August, and were undetectable by late August. Preventative acaricide-treated plots in 2016 tended to have significantly lower mite densities than in the untreated control plots. Although in 2017, densities in the acaricide-treated plots tended to not significantly differ from control plots. Mite feeding injury, measured as mean cumulative mite-days, did not exceed the economic threshold during the experiment. The biological control agent, sixspotted thrips, Scolothrips sexmaculatus (Pergande) likely played a role in controlling mite populations at mid and late August. Our results indicate that a preventative strategy does not play a definitive role in T. pacificus management on almond. Additionally, acaricides with the active ingredient, abamectin, are heavily relied on as preventative treatments. We assessed populations of T. pacificus from the mid and southern San Joaquin Valley and found increased tolerance to a medium level of resistance to the acaricide.

A life stage-targeted acaricide application approach for the control of Haemaphysalis longicornis

Haemaphysalis longicornis Neumann is an invasive tick species that has recently been detected in the eastern United States. We designed field studies to monitor the population dynamics of H. longicornis over a year (2019) in New Jersey, and to assess the efficacy of a pyrethroid acaricide (lambda-cyhalothrin) in controlling this tick using a stage-treatment approach. Nymphs were the most abundant life stage found host-seeking from May through early July, followed by a brief period of high adult activity in mid-July, and a very high larval peak extending from late July through October. Overall, 542 adults, 1910 nymphs, and 69,238 larvae were recorded during the sampling. In the present study, the efficacy of acaricide treatments to suppress host-seeking ticks was assessed by applying lambda-cyhalothrin once during each of the three periods of activity for nymphs (June), adults (July), and larvae (August), or sequentially during all three months. Control plots were left untreated and used for phenology studies. Applications in June and July provided 100 % control of all life stages, including the dominant nymphal and adult stages for 42 and 35 d, respectively. Ticks re-established at normal or reduced levels following applications in June or July, respectively, compared to untreated controls. The application in August provided 100 % control for 49 d, and a high level of suppression (>99 % control) remained through the end of the tick season in October. This study therefore supports that single pyrethroid applications can provide 100 % control of H. longicornis for up to 7 wk, and a single late-summer application towards the end of host-seeking adult activity can provide near complete control of the larval population. An evaluation of single applications over the course of the season revealed that treatments in July or August did not lead to significant reductions in the nymphal population. However, multiple sequential treatments targeting all life stages provided 66 %, 97 %, and >99 % control of adults, nymphs, and larvae, respectively through the season of H. longicornis activity.

Assessing the resistance to acaricides in Varroa destructor from several Spanish locations.

Varroosis is the disease caused by the ectoparasitic mite Varroa destructor, one of the most destructive diseases of honeybees. In Spain, there is great concern because there are many therapeutic failures after acaricide treatments intended to control varroosis outbreaks. In some of these cases it is not clear whether such failures are due to the evolution of resistance. Therefore, it is of high interest the development of methodologies to test the level of resistance in mite populations. In this work, a simple bioassay methodology was used to test whether some reports on low efficacy in different regions of Spain were in fact related to reduced Varroa sensitivity to the most used acaricides. This bioassay proved to be very effective in evaluating the presence of mites that survive after being exposed to acaricides. In the samples tested, the mortality caused by coumaphos ranged from 2 to 89%; for tau-fluvalinate, it ranged from 5 to 96%. On the other hand, amitraz caused 100% mortality in all cases. These results suggest the presence of Varroa resistant to coumaphos and fluvalinate in most of the apiaries sampled, even in those where these active ingredients were not used in the last years. The bioassay technique presented here, either alone or in combination with other molecular tools, could be useful in detecting mite populations with different sensitivity to acaricides, which is of vital interest in selecting the best management and/or acaricide strategy to control the parasite in apiaries.

Differentiation of Transbaikal Territory by Tick-Borne Viral Encephalitis Incidence

Objective of the study was to differentiate the Administrative Districts of theTransbaikalTerritory at the time of Tick-borne viral encephalitis (TBVE) incidence recession by epidemiological risk groups and to characterize them by volume of specific and nonspecific preventive measures.Materials and methods. Retrospective analysis of TBVE epidemiological situation is based on the statistical reporting data “Information on infectious and parasitic diseases” in 2009–2019 and other materials of the Rospotrebnadzor Administration in the Transbaikal Territory. The clustering of areas with various levels of epidemiological risk was conducted by calculation of 95 % confidential interval for long-term annual average of TBVE cases in municipal units of the Territory over a decade and assessment of appurtenance of the deviating values to the aggregate under study.Results and discussion. Twenty four out of 32 districts of the Transbaikal Territory are endemic for TBVE. These areas are divided into five groups: with very high epidemiological risk (2 districts), high (5), medium (8), and low (8) risk respectively, as well as the administrative center of the constituent entity which by the whole complex of indicators (disease manifestation, population density, factors of targeted TBVE decrease, social-and-living and economical conditions) cannot be considered together with the rest of municipalities. Each group of the districts was characterized by the number of cases and TBVE incidence rates, medical aid seeking by persons who suffered from tick bites, vaccination volumes, seroprevention, areas of acaricide treatments. Recommendations are presented for the essential complex and scope of measures to prevent TBVE in the groups of administrative districts that differ by the level of epidemiological risk.

Analysis of the epidemic situation of tick-borne viral encephalitis in the Republic of Altai in 2000-2017

Introduction. The Republic of Altai is one of the regions of the Siberian Federal District endemic for tick-borne encephalitis with high altitude mountain belts with characteristic landscape and climatic conditions. The purpose of this study is to analyze the epidemiological situation of tick-borne encephalitis in the Republic of Altai from 2000 to 2017. Material and methods. In conducting a retrospective epidemiological study, data from sanitary-epidemiological and medical services for 2000-2017 were used. Statistical data processing was carried out with the software “Statistica 12.0”, the construction and analysis of cartograms - with the software ArcGIS. Results. The average long-term incidence rate of this infection in the period from 2000 to 2017 amounted to 21.7 ± 0.76 0/0000, which is 2.2 times higher than the similar indexby for the SFO (10.1 ± 0.23 0/0000). The number of persons affected by tick infestation in the period from 2000 to 2017 increased 3.5 times from 517.7 ± 15.95 0/0000 to 1810.5 ± 28.62 0/0000, respectively (p &lt;0.001). Ranking on the level of the average long-term incidence allowed identifying three groups of the potential risk of infection of the population. Discussion. The factor analysis revealed the presence of an inverse correlation between the incidence of tick-borne encephalitis and the levels of seroprophylaxis (r = -0.93), acaricidal treatments (r = -0.95), vaccination (r = -0.10). The calculated levels of these factors were determined according to the results of the construction of spatial models of their mutual influences, capable of reducing the number of cases in the region to 6 per year. Conclusion. An analysis of the epidemic situation based on factor analysis and spatial modeling of the mutual influence of factors made it possible to determine the necessary volumes of preventive measures to reduce the incidence of the population to a given level. Such a calculation may be applicable in an endemic region to ensure the medical and economic effectiveness of preventive measures.

Analysis of the epidemic situation of tick-borne viral encephalitis in the Republic of Altai in 2000-2017

Introduction. The Republic of Altai is one of the regions of the Siberian Federal District endemic for tick-borne encephalitis with high altitude mountain belts with characteristic landscape and climatic conditions. The purpose of this study is to analyze the epidemiological situation of tick-borne encephalitis in the Republic of Altai from 2000 to 2017. Material and methods. In conducting a retrospective epidemiological study, data from sanitary-epidemiological and medical services for 2000-2017 were used. Statistical data processing was carried out with the software “Statistica 12.0”, the construction and analysis of cartograms - with the software ArcGIS. Results. The average long-term incidence rate of this infection in the period from 2000 to 2017 amounted to 21.7 ± 0.76 0/0000, which is 2.2 times higher than the similar indexby for the SFO (10.1 ± 0.23 0/0000). The number of persons affected by tick infestation in the period from 2000 to 2017 increased 3.5 times from 517.7 ± 15.95 0/0000 to 1810.5 ± 28.62 0/0000, respectively (p &lt;0.001). Ranking on the level of the average long-term incidence allowed identifying three groups of the potential risk of infection of the population. Discussion. The factor analysis revealed the presence of an inverse correlation between the incidence of tick-borne encephalitis and the levels of seroprophylaxis (r = -0.93), acaricidal treatments (r = -0.95), vaccination (r = -0.10). The calculated levels of these factors were determined according to the results of the construction of spatial models of their mutual influences, capable of reducing the number of cases in the region to 6 per year. Conclusion. An analysis of the epidemic situation based on factor analysis and spatial modeling of the mutual influence of factors made it possible to determine the necessary volumes of preventive measures to reduce the incidence of the population to a given level. Such a calculation may be applicable in an endemic region to ensure the medical and economic effectiveness of preventive measures.

Communal cattle farmer’s knowledge, attitudes and practices on ticks (Acari: Ixodidae), tick control and acaricide resistance

The aim of this study was to reveal communal farmer's knowledge, attitudes and practice on ticks and tick-borne diseases affecting cattle, tick control methods used and their knowledge on acaricide resistance. A total of 160 structured questionnaires are prepared and randomly administered to cattle farmers in Sinqu and Elundini communities in the Eastern Cape Province, South Africa. Associations between the area, gender, age, employment, source of income, level of education and farming experience were statistically tested using Chi-square test. Gall sickness (63%) was the most prevailing tick-borne disease in cattle during the summer season (61%). About 59% of the farmers had no knowledge of the effect of tick-borne diseases on cattle production, and 78% of respondents reported that ticks are the major challenge to cattle farming. Pour-on (61%) was the most commonly used acaricidal treatment system with every fortnight (40%) treatment frequency during the summer season and (31%) during the winter season. Pyrethroids (73%) were the most used acaricide compounds to control ticks, and about 65% of respondents perceived to have no knowledge of the use of ethnoveterinary medicines used to control ticks. Inefficacy of acaricide (44%) and undipped animals (42%) were regarded as the major contributing factors to the increased tick population and acaricide resistance. About 85% of respondents perceived that they do not practice acaricide rotation and 88% of the respondents had no knowledge of the acaricide resistance. Within the context of this study, ticks and tick-associated diseases are perceived by these farmers as the most important disease problem their cattle face. Thus, knowledge regarding the epidemiology of ticks and tick-borne diseases is key to control strategies, and farmer training should be encouraged to achieve better control of ticks and the diseases they transmit.

Epidemiological Situation on Tick-Borne Viral Encephalitis in the Russian Federation in 2019 and Forecast for 2020

Tick-borne encephalitis is a transmissible natural-focal disease which occurs in some countries across Europe and Asia. The observation of epidemic process dynamics of TBVE in Russia covers an 80-year long period and it’s the world longest. The existence of extensive records, various data from different geographic and administrative areas opens the way to interpretation of certain ecological and social factors and their role in the regional epidemiological situation. The targeted measures against TBVE are feasible only when the role of basic predictors of decreasing incidence is defined. Objective: analysis of TBVE incidence among the population and preventive measures in the Districts and constituent entities of Russia in 2019, forecast for 2020 based on the data collected in 2010–2019. The article shows a continued downward trend in TBVE incidence, noted in recent years. However, cases of infection were registered in 6 Federal Districts and 46 regions just like in the past. The number of patients amounted to 1559 (the incidence rate is 1.02 per 100000 people), of whom 23 have died. The rate of seeking medical care among those who were bitten by ticks increased. Specific preventive measures against TBVE haven’t significantly changed by volume and focus compared to the previous period. The scope of acaricide treatments has declined. The article also presents the data concerning TBVE carriers’ infection rate, and the laboratory study results in districts and regions across the country. It is recognized that the epidemiological situation on TBVE in Russia is still unfavorable. It requires the constant attention of health facilities and Rospotrebnadzor and management decisions aimed at further decrease in the incidence by improved prevention especially in the regions with high TBVE incidence.