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Ovine anaplasmosis is causing relevant economic losses in Spain due to icteric carcass condemnation in lambs. Anaplasma ovis infection occurs through grazing sheep that transfer ticks to their offspring. This study compared the efficacy of deltamethrin and cypermethrin pour-on treatments for tick control. A total of 250 PCR A. ovis-positive ewes and their offspring were divided into 5 groups. Group A (50 ewes/50 lambs) was kept as an untreated control group. In groups B (50/50) and C (45/93), the lambs were treated with deltamethrin pour-on and cypermethrin pour-on, respectively, one week after birth. In groups D (50/75) and E (51/68), the ewes were treated with cypermethrin pour-on and deltamethrin pour-on one week before the estimated parturition. External parasite assessment and A. ovis PCR were conducted before treatment and at 21 and 42 days post-treatment. Ewes were checked weekly for tick-detection until weaning. Lamb carcasses were examined at the slaughterhouse. Riphicephalus sanguineus sensu lato ticks were found in ewes throughout the study, with only one tick found in a control group lamb. Three lambs tested positive for A. ovis during the trial, with one condemnation at the abattoir due to jaundice. However, no significant differences were observed between treatment groups. Overall, a significant decrease in infected animals and condemned carcasses was observed compared to previous years, suggesting that deltamethrin and cypermethrin prevent A. ovis transmission from dams to lambs. Further studies are needed to confirm synthetic pyrethroids' effectiveness in controlling tick infestation and averting A. ovis transmission to lambs., (© 2024. The Author(s).)

The number of tick-borne disease cases continues to rise in the United States, with Lyme disease the most frequently reported vector-borne disease nationally. Practical and effective tick control tools and strategies are needed to reduce tick encounters and tick-borne disease risk. Tick management tubes have shown varying efficacy when used as part of a tick management plan. To evaluate factors contributing to the efficacy of tick management tubes, this study assessed changes in tick tube deployment on tick burden on wild-caught Peromyscus mice, a primary reservoir for the bacterium causing Lyme disease, in Pennsylvania from 2021 to 2023. Over 2 years, tick tubes were deployed starting at different times of the year, with cotton removal from the tubes assessed every 2 weeks from April to November and tick burden on wild-caught mice assessed every 2 months from April to October of each year. The effect of distance between tick management tubes was assessed in year 3 of this study, with mouse tick burden assessed pre- and post-treatment with tick tubes at varying intervals in a field setting. There was a significant reduction in mouse tick burden between treated and control transects, and pre- and post-treatment transects. Tick tube distance did not affect cotton removal or tick burden on mice. Still, cotton removal was highest in September-October, and amount removed increased the longer tick tubes were deployed in the field, highlighting the long-term benefits of using tick tubes as part of an integrated tick management plan. Future investigations to evaluate the impact of tick management tubes on tick nymph density and infection would be valuable for assessing the effectiveness of tick management tubes in reducing tick bite risk., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

The mixture of pesticides is widely employed in cattle farming to combat ectoparasite resistance, such as ticks. The commercial formulation COLOSSO FC30, which contains three active ingredients (Cypermethrin, Chlorpyrifos, and Fenthion), stands out due to its efficiency. However, animals exposed to this product may become vectors of potentially toxic molecules, possibly causing contamination in aquatic and terrestrial ecosystems. In light of this, this study evaluated the eco(geno)toxic potential of the commercial formulation COLOSSO FC30, using plants (Allium cepa L., Lactuca sativa L., Raphanus sativus L., Pennisetum glaucum L., and Triticum aestivum L.) and Artemia salina L. as model organisms. In the phytotoxicity test, the species were ranked in order of sensitivity to the commercial formulation as follows: P. glaucum > L. sativa > T. aestivum > R. sativus. The most sensitive parameters were root length (RL) and shoot length (SL) of seedlings. In the cytogenotoxicity test with A. cepa, cell division was decreased at concentrations from 0.351 mL L -1 in the meristematic region and root F1. Chromosomal aberrations and micronucleus were observed at all concentrations. In the test with A. salina, the IC 50 after 24 h of exposure was 0.01207 mL L -1 of the commercial formulation. The results highlight the need for further research and regulations to understand and minimize the potential environmental impacts of COLOSSO FC30., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Relationship between fluazuron (FZN) concentrations in cattle plasma and ticks and its therapeutic efficacy percentage (EP) against Rhipicephalus microplus was analyzed. The extent of FZN uptake by ticks after its topical administration was also evaluated. Heifers, naturally infested with R. microplus, were divided in treated and no treated groups. Blood and tick samples were taken to measure FZN concentrations and female ticks were counted to evaluate the EP of the treatment from day 0 to 45 post-treatment (PT). Ticks exposed (TE) and not exposed (TNE) to topical contact with the drug were collected at 12 and 24 h PT. Artificial feeding (AF) of ticks was also performed with blood from a treated heifer. The EP on days 21, 28, 35, 42 and 45 PT was 99.1, 92.3, 81.2, 74.7 and 76.5 %, respectively. Fluazuron disposition within ticks during the first 2 days post-treatment did not mirror the corresponding FZN levels in the bovine plasma, but a statistically significant positive correlation was evident from day 3. Mean FZN concentrations in TE at 12 h and 24 h PT were significantly higher than in TNE. The FZN concentrations in AF ticks were significantly lower than those in TE but comparable to the levels in TNE. The efficacy and pharmacokinetics analysis suggest that maintaining a threshold FZN plasma concentration above 20-25 ng/mL is crucial to prevent the development of larvae into engorged females. The results also indicate that direct absorption of FZN through the tick's integument occurs in the initial days after treatment., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Currently, the primary strategy for tick control relies on chemical agents. Pyrethrins, which are botanically derived compounds, have demonstrated efficacy in controlling ticks without posing a risk to human or animal health. However, research into pyrethrins' metabolic mechanisms remains sparse. Cystatin, as a reversible binding inhibitor of cysteine protease, may be involved in the initiation of pyrethrin detoxification of Haemaphysalis doenitzi. In this study, two novel cystatins were cloned, HDcyst-3 and HDcyst-4, the relative expression of which was highest in the Malpighian tubules compared with the tick midguts, salivary glands, and ovaries. Prokaryotic expression and in vitro studies revealed that cystatins effectively inhibit the enzymatic activities of cathepsins B and S. RNAi results showed that the reduction of cystatins significantly decreased the engorgement weight, egg mass weight, and egg hatching rate of adult female ticks, and prolonged feeding time by two days. The control rate of rHDcyst-3 and rHDcyst-4 protein vaccination against female adults were 55.9% and 63.2%, respectively. In addition, the tick immersion test showed that cypermethrin and λ-cyhalothrin had significant acaricidal effects against adult unfed H. doenitzi. The qPCR result indicated that compared with the control group, the expression of HDcyst-3 and HDcyst-4 was markedly decreased in the sublethal cypermethrin and λ-cyhalothrin group at LC 50 . Enzyme activity showed that cypermethrin and λ-cyhalothrin could significantly induce the activities of glutathione S-transferase (GST), carboxylesterase (CarE), and acetylcholinesterase (AchE). The aforementioned results provided indirect evidence that cystatin plays an important role in pyrethrin detoxification and provides a theoretical basis for future acaricide experiments and pest management., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier Inc.)

Amblyomma sculptum is widely distributed in Brazil and is the main vector of Rickettsia rickettsii, the causative agent of the Brazilian spotted fever (BSF). Tick gut proteins play an essential role in blood feeding, digestion, and protection of gut epithelium. Therefore, many of these were investigated as potential vaccine targets for tick-control strategies. The present study aimed to select transcripts corresponding to putative immunogenic proteins in the A. sculptum gut epithelial membrane, produce recombinant proteins and evaluate them as antigens against A. sculptum infestations. Three gut proteins - AsMucin, AsAPP, and AsLAMP - and a chimeric protein (rAsChimera) based on 22 peptides containing putative B cell epitopes from seven different gut proteins were evaluated as anti-A. sculptum antigens. Mice immunizations revealed that all recombinant targets elicited humoral response with significantly increased IgG levels compared to controls. For rAsChimera, IgG levels remained significantly higher than controls up to 75 days after the end of the immunization. Challenge trials revealed that vaccination with the chimeric protein was the most effective against A. sculptum, inducing 100 % nymph mortality and reaching 80.8 % efficacy against females. The other three proteins did not induce relevant protection, as AsAPP had only 26.6 % efficacy, whereas AsMucin and AsLAMP induced no protection. These data indicate that targeting gut protein immunogenic regions may be an effective strategy for a vaccine formulation againstA. sculptum., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Ricardo Nascimento Araujo has patent #BR 10 2019 018609 7 pending to INPI- Instituto Nacional de Propriedade Intelectual. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Tick infestation poses an important challenge to livestock in Pakistan. Farm management practices and environmental variables can influence tick infestation prevalence in animals. To this end, a cross-sectional survey of 96 farms in four different geographical districts (24 farms from each district) was conducted in Punjab, Pakistan, between October 2021 and January 2022. An epidemiological questionnaire was designed focusing on farm management practices and their impact on tick infestations at these farms. Data were collected via in-person interviews. Regional and farm-specific variables' associations were evaluated using Pearson's chi-square test and Fischer's exact test, respectively. A multivariable logistic regression model was used to identify significant risk factors. This study identified that using soft bedding materials, e.g., wheat straw, leaf litter or plain soil posed a significant risk of tick infestation. Additionally, the absence of quarantine measures, open sheds and inadequate drainage were found as contributing factors in univariable analysis. Higher tick prevalence in the hotter seasons highlighted the influence of Punjab's extreme weather on tick infestation. Despite regular veterinary visits and the use of acaricidal drugs, the prevalence of tick infestation at these farms suggested potential drug resistance in the ticks. The study recommended establishing quarantine practices, improving farms' drainage systems and bedding and using a combination of chemical and traditional remedies to tackle drug resistance in ticks. Education and awareness programs on tick-borne diseases and control measures are advocated to reduce the tick infestation burden on animals. Further research on longitudinal studies to better understand tick population dynamics and develop effective acaricides is encouraged. This called for collaborative control efforts among farmers, veterinarians and research institutions.

The progressing worldwide increases in tick occurrence and tick-borne diseases calls for the development of new prevention strategies to reduce their impact on human and animal health. Defining the risk of exposure to tick bites is therefore essential. Forestry workers are at high risk of tick bites. We set up an explorative study among forestry workers in the Alsace region in eastern France to measure the different factors affecting the risk of Ixodes ricinus tick bites during their activities in forests. For one year, forestry workers recorded the presence of ticks on their clothes and tick bites every time they were working in teams in different forest ecosystems. Questions about the prevention measures they followed were also noted. Among the 32 participants, we were able to differentiate between groups having a high, neutral, or low risk of being bitten. The median tick bite number per year was 4 (0-8). We tried to identify individual as well as environmental factors affecting the risk of tick bites. Factors influencing the risk were the seasonal peak of tick activity in May and June, the time of exposure, and the forest ecosystems visited during the year. Additional factors potentially affecting the risk were also identified.

Background: Lyme disease continues to expand in Canada and the USA and no single intervention is likely to curb the epidemic., Methods: We propose a platform to quantitatively assess the effectiveness of a subset of Ixodes scapularis tick management approaches. The platform allows us to assess the impact of different control treatments, conducted either individually (single interventions) or in combination (combined efforts), with varying timings and durations. Interventions include three low environmental toxicity measures in differing combinations, namely reductions in white-tailed deer (Odocoileus virginianus) populations, broadcast area-application of the entomopathogenic fungus Metarhizium anisopliae, and fipronil-based rodent-targeted bait boxes. To assess the impact of these control efforts, we calibrated a process-based mathematical model to data collected from residential properties in the town of Redding, southwestern Connecticut, where an integrated tick management program to reduce I.xodes scapularis nymphs was conducted from 2013 through 2016. We estimated parameters mechanistically for each of the three treatments, simulated multiple combinations and timings of interventions, and computed the resulting percent reduction of the nymphal peak and of the area under the phenology curve., Results: Simulation outputs suggest that the three-treatment combination and the bait boxes-deer reduction combination had the overall highest impacts on suppressing I. scapularis nymphs. All (single or combined) interventions were more efficacious when implemented for a higher number of years. When implemented for at least 4 years, most interventions (except the single application of the entomopathogenic fungus) were predicted to strongly reduce the nymphal peak compared with the no intervention scenario. Finally, we determined the optimal period to apply the entomopathogenic fungus in residential yards, depending on the number of applications., Conclusions: Computer simulation is a powerful tool to identify the optimal deployment of individual and combined tick management approaches, which can synergistically contribute to short-to-long-term, costeffective, and sustainable control of tick-borne diseases in integrated tick management (ITM) interventions., (© 2024. The Author(s).)

Rhipicephalus microplus poses a significant economic threat due to its role in transmitting Babesia bigemina, B. bovis and Anaplasma marginale. Chemical control methods, commonly employed, encounter challenges like resistance, high costs, and environmental concerns. Emerging as an alternative, entomopathogenic fungi, particularly Beauveria bassiana, present a promising avenue for biological control. Molecular identification using the internal transcribed spacer (ITS1-5.8-ITS4) region ensures accurate species identification. This study investigated two B. bassiana strains, assessing their molecular characterization, impact on R. microplus mortality, and reproductive effects on adult females. The Reproductive Aptitude Index (RAI) is employed to evaluate tick egg viability post-treatment, providing insights into the potential of these fungi for tick control. Results indicate the BbLn2021-1 strain causes 96% mortality, and BbSf2021-1 induces 100% mortality. The commercial strain exhibited 28% mortality, while the control treatment showed 12%. Statistical analysis reveals a significant difference between treatments (p < 0.01). The Reproductive Efficiency Index (REI) underscores BbSf2021-1is superiority, yielding lower egg weights than other treatments. Regarding the RAI, BbLn2021-1 and BbSf2021-1 show no significant differences but differ significantly from the commercial and control (p < 0.01). These findings suggest that strains isolated and characterized from the natural environment could have potential applications in field trials, serving as a biocontrol alternative for R. microplus ticks., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

One of the most damaging pests of agricultural crops across the globe is the two-spotted spider mite, Tetranychus urticae Koch. A wide variety of arthropods and plant pathogens can be controlled by essential oils, which are secondary metabolites produced by plants. It is possible to enhance the stability as well as the anti-pest efficiency of plant essential oils by encapsulation. Water distillation was used to extract the essential oils from Eucalyptus globulus and Ferula assafoetida. The chitosan nanoparticles were used to load both essential oils into nanoformulations. Studies were conducted on T. urticae life table characteristics under experimental circumstances to determine the sublethal impacts of essential oils and their nanoformulations. Intrinsic growth rate (r) for population exposed to E. globulus, F. assafoetida essential oils, their nanoformulations and the control were 0.1, 0.069, 0.051, 0.018 and 0.21 per day, respectively. F. assafoetida and E. globulus nanoformulations resulted the lowest fecundity compared to the other treatments. According the result of the lethal and sublethal effects of purified essential oils and nanoformulations of F. assafoetida and E. globulus, they would be recommended for controlling the two-spotted spider mites, T. urticae., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Ticks, which are obligate blood-feeding parasites, transmit a wide range of pathogens during their hematophagic process. Certain enzymes and macromolecules play a crucial role in inhibition of several tick physiological processes, including digestion and reproduction. In the present study, genes encoding type 2 cystatin were cloned and characterized from Haemaphysalis doenitzi, and the potential role of cystatin in tick control was further assessed., Results: Two cystatin genes, HDcyst-1 and HDcyst-2, were successfully cloned from the tick H. doenitzi. Their open reading frames are 390 and 426 base pairs, and the number of coding amino acids are 129 and 141, respectively. In the midgut, salivary glands, Malpighian tubules and ovaries of ticks, the relative expression of HDcyst-1 was higher in the midgut and Malpighian tubules, and HDcyst-2 was higher in the salivary glands of H. doenitzi, respectively. Lipopolysaccharide (LPS) injection and low-temperature stress elevated cystatin expression in ticks. Enzyme-linked immunosorbent assay showed that both rHDcyst-1 and rHDcyst-2 protein vaccines increased antibody levels in immunized rabbits. A vaccination trial in rabbits infected with H. doenitzi showed that both recombinant cystatin proteins significantly reduced tick engorgement weights and egg mass weight, in particular, rHDcyst-1 significantly prolonged tick engorgement time by 1 day and reduced egg hatching rates by 16.9%. In total, rHDcyst-1 and rHDcyst-2 protein vaccinations provided 64.1% and 51.8% protection to adult female ticks, respectively., Conclusion: This is the first report on the immunological characterization of the cystatin protein and sequencing of the cystatin gene in H. doenitzi. Cystatin proteins are promising antigens that have the potential to be used as vaccines for infestation of H. doenitzi control. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Background: The vast majority of vector-borne diseases in the USA are associated with mosquitoes or ticks. Mosquito control is often conducted as part of community programs run by publicly-funded entities. By contrast, tick control focuses primarily on individual residential properties and is implemented predominantly by homeowners and the private pest control firms they contract. We surveyed publicly-funded vector control programs (VCPs), presumed to focus mainly on mosquitoes, to determine what tick-related services they currently offer, and their interest in and capacity to expand existing services or provide new ones., Methods: We distributed a survey to VCPs in the Northeast, Upper Midwest and Pacific Coast states of the USA, where humans are at risk for bites by tick vectors (Ixodes scapularis or Ixodes pacificus) of agents causing Lyme disease and other tick-borne diseases. The data we report are based on responses from 118 VCPs engaged in vector control and with at least some activities focused on ticks., Results: Despite our survey targeting geographic regions where ticks and tick-borne diseases are persistent and increasing public health concerns, only 11% (12/114) of VCPs reported they took direct action to suppress ticks questing in the environment. The most common tick-related activities conducted by the VCPs were tick bite prevention education for the public (70%; 75/107 VCPs) and tick surveillance (48%; 56/116). When asked which services they would most likely include as part of a comprehensive tick management program, tick bite prevention education (90%; 96/107), tick surveillance (89%; 95/107) and tick suppression guidance for the public (74%; 79/107) were the most common services selected. Most VCPs were also willing to consider engaging in activities to suppress ticks on public lands (68%; 73/107), but few were willing to consider suppressing ticks on privately owned land such as residential properties (15%; 16/107). Across all potential tick-related services, funding was reported as the biggest obstacle to program expansion or development, followed by personnel., Conclusions: Considering the hesitancy of VCPs to provide tick suppression services on private properties and the high risk for tick bites in peridomestic settings, suppression of ticks on residential properties by private pest control operators will likely play an important role in the tick suppression landscape in the USA for the foreseeable future. Nevertheless, VCPs can assist in this effort by providing locally relevant guidelines to homeowners and private pest control firms regarding best practices for residential tick suppression efforts and associated efficacy evaluations. Publicly-funded VCPs are also well positioned to educate the public on personal tick bite prevention measures and to collect tick surveillance data that provide information on the risk of human encounters with ticks within their jurisdictions., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Based on increases in reported cases of tick-borne illnesses, expanding ranges of native ticks, and repeated documentation of arrivals of nonnative tick species, there is a clear need for their effective management in the United States. Synthetic acaricides have proven efficacious in tick management, but real/perceived negative impacts to the environment and nontarget, beneficial insects must be addressed. We sought to determine whether late fall synthetic acaricide application, when most susceptible beneficial insects are presumably dormant or have migrated, could effectively manage host-seeking spring Ixodes scapularis Say abundances as compared to traditional spring application. We compared results of delivery of Demand CS (lambda-cyhalothrin) via truck-mounted high-pressure spray and powered backpack blower as well as delivery of granular Demand G to experimental control (water) in peridomestic habitats in fall 2021, spring 2022, and combined fall 2021/spring 2022. High-pressure fall delivery of Demand CS and backpack delivery of Demand G significantly reduced host-seeking adult I. scapularis abundances within-season and the following spring combined by 100% and 94%, respectively. No host-seeking nymphal I. scapularis were documented in spring after fall only, spring only, or fall and spring combined delivery of Demand CS via high-pressure or powered backpack blower. No adult I. scapularis were documented at any time posttreatment on locations that received high-pressure delivery of Demand CS. We conclude that high-pressure delivery of Demand CS in late fall successfully eliminated multiple stages of host-seeking I. scapularis through the following spring while likely limiting exposure of beneficial insects to synthetic pyrethroids., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

White-tailed deer, Odocoileus virginianus Zimmermann (Artiodactyla: Cervidae), are the primary wildlife host for adult stages of blacklegged ticks (Acari: Ixodidae: Ixodes scapularis Say) and an important host for lone star ticks (Acari: Ixodidae: Amblyomma americanum Linnaeus), both of which are vectors of numerous tick-borne pathogens. The 4-poster passive deer treatment device is a topical, host-targeted method to control free-living tick populations and has been proven to successfully reduce tick abundance in several states. Aggressive behavior of white-tailed deer at concentrated feeding stations is hypothesized to interfere with the effective use of 4-poster devices and deer contact with acaricide applicators. We analyzed images collected by camera traps at 4-poster feeding stations deployed at 3 sites in Maryland and found a negative relationship between some aggressive interactions and contact with applicators. Our results emphasize the need for further investigation into whether deer social dynamics can impact 4-poster efficacy for tick control. This study serves as a reminder that intraspecific interactions are important to consider when using host-targeted acaricide approaches., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

This study aimed to evaluate the acaricidal potential of the essential oils of Cananga odorata L. (ylang-ylang), Illicium verum (star anise), and Foeniculum vulgare (sweet fennel) in Rhipicephalus microplus engorged females. The essential oils were extracted by hydrodistillation, and the females were immersed in each essential oil at concentrations ranging from 10 μL/mL to 50 μL/mL, using 10% dimethyl sulfoxide as a solvent. Tick mortality was evaluated after seven and 14 days, and the following parameters were determined: female weight before oviposition, preoviposition period, egg mass weight, egg production index, incubation period, hatching rate, fecundity, percentage of reduction in oviposition, percentage of reduction in hatching and product efficacy. Lethal concentration (LC 50 ) values were 34.42 μL/mL (28.34-40.86) for C. odorata and 40.60 μL/mL (32.58-58.21) for F. vulgare. This parameter was not calculated for I. verum because there was insufficient mortality at the concentrations evaluated. The greatest efficacy was observed in the group treated with 40 μL/mL F. vulgare essential oil (97.17%), followed by I. verum (91.35%) and C. odorata (86.19%) at the same concentration. Efficacy results were associated with a greater reduction in egg mass weight and lower hatching rates. Although the essential oils caused a slight acaricidal impact, they showed significant effects on the reproductive performance of R. microplus engorged females. Thus, the results of this study indicate that these essential oils can be used in the development of new acaricidal formulations., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Ticks are parasitic arthropods that cause significant economic losses to livestock production worldwide. Although Rhipicephalus (Boophilus) microplus, the cattle tick, occurs throughout the Brazilian territory, there is no official program to control this tick, which is the vector of tick fever pathogens. We address the situation of R. (B.) microplus resistance to synthetic acaricides in Brazil, including cattle tick management; the status of tick resistance per Brazilian state; the history of resistance occurrence of different acaricides; multiple resistance occurrence; and the main strategies for integrated tick management. Tick control in Brazil is characterized by management errors. Local laboratories affiliated with federal and state research institutions and universities employ the Adult Immersion Test as a primary diagnostic method to assess acaricide resistance to topically applied drugs. Only three states (Acre, Amapá, and Amazonas) have no reports on resistant populations. Misinformation on tick control strategies, misuse of available products for tick control, no adoption of Integrated Parasite Management (IPM) practices, low technical support to producers, and the high-speed emergence of acaricide-resistant tick populations are the main problems. We also propose a list of needs and priorities for cattle tick control regarding communication, research, and policies.

Habitat manipulation such as intercropping can be used as a simple and common cultural practice in pest management. This method is based on the principle of reducing pest populations by increasing the diversity of an ecosystem. This study has been carried out to evaluate the influence of additive series intercropping common bean with some aromatic plants (AP), and 2 acaricides on the different life stages (egg, immature mobile stages, and adult) of Tetranychus urticae Koch (Trombidiformes: Tetranychidae), over 2 yr of experimentation (2020 and 2021). This experiment was conducted following a randomized complete block design with 7 treatments including common bean monoculture, common bean sprayed by spiromesifen or Dayabon, and common bean + companion plants (coriander, ajwain, basil, or dill). Each treatment was replicated 3 replicates. The lowest and highest number of eggs, immature mobile stages, and adults were observed in common bean + spiromesifen and the common bean monoculture, respectively. Additionally, the common bean + Dayabon supported significantly different T. urticae life stage densities compared to common bean monoculture. Also, among intercropped treatments, common bean + basil showed the lowest number of T. urticae (eggs, immature mobile stages, and adults). The highest yield and land equivalent ratio were recorded in common bean + basil and common bean + spiromesifen, respectively. Finally, it can be concluded that additive intercropping with these AP can effectively decrease the T. urticae population density, which is useful for the safe production of common bean., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

In a nature reserve in southern Maine, we removed invasive Japanese barberry (Berberis thunbergii de Candolle) along sections of forested recreational trails that ran through dense barberry infestations. Barberry thickets provide questing substrate and a protective microclimate for blacklegged ticks (Ixodes scapularis Say), and trail users could brush up against encroaching barberry and acquire ticks. Trailside barberry removal will reduce or eliminate encroaching tick questing substrate and could reduce trailside questing tick abundance by creating a microclimate more hostile to ticks. The same-day cut-and-spray treatment comprised mechanical cutting of barberry clumps (individual plants with numerous ramets) followed immediately by targeted herbicide application to the resulting root crowns. The treatment created trail shoulders to a lateral width of 1-2 m on both sides of 100-m trail sections, with initial treatment in the fall of 2013 and one retreatment in the summer of 2014. Our aim was to remove 90% of barberry clumps to achieve a 50% or better reduction in questing tick abundance on trail shoulders. However, by the fall of 2015, there were only 41% fewer barberry clumps on treated vs. untreated trail sections and there was no reduction in either adults or nymphs. We concluded that our barberry treatment protocol was not sufficiently aggressive since the resulting ecotone habitat on trail shoulders proved suitable for questing I. scapularis. In principle, cutting back barberry along trails should reduce trail user contact with questing deer ticks, but we were unable to demonstrate a reduction in trailside tick abundance., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Ticks and tick-borne diseases have gained increasing attention in recent years due to their impact on public health and significant losses in livestock production. The use of synthetic compounds for tick control is becoming problematic, mainly due to the resistance to commercially available products as well as their toxicity. Therefore, new alternative control methods are required. For this purpose, plant-derived extracts may be considered as effective repellents and/or acaricides. The present literature review focuses on studies evaluating the acaricidal and repellent activity of plant-derived extracts and plant secondary metabolites. We also noted recent advances in protein-ligand-docking simulation to examine the possible toxic effect of natural chemical compounds on ticks. In conclusion, plant-derived repellents/acaricides can be effective against ticks, especially in rural areas and livestock farms., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Application of chemical acaricides in the control of ticks has led to the problem of tick-acaricide control failure. To obtain an understanding of the possible risk factors involved in this tick-acaricide control failure, this study investigated tick control practices on communal farms in the north-eastern part of the Eastern Cape Province (ECP) of South Africa. A semi-structured questionnaire designed to document specific farm attributes and acaricide usage practices was administered at 94 communal farms from the Oliver Tambo District municipality of the ECP. Data collected indicated that the main acaricide chemicals used at plunge dips of inland and coastal areas were synthetic pyrethroid formulations. Most (75%) farmers claimed not to have noticed a significant reduction in numbers of actively feeding and growing ticks on cattle after several acaricide treatments. Based on the farmers' perceptions, leading factors that could have led to tick-acaricide control failure included: weak strength of the dip solution (76%); poor structural state of dip tanks (42%); and irregular tick control (21%). The rearing of crossbreeds of local and exotic cattle breeds, perceived weak strength of the dip solution and high frequency of acaricide treatment, were statistically associated with proportions of farms reporting tick-acaricide control failure. Furthermore, approximately 50% of farms reported at least four tick control malpractices, which could have resulted in the emergence and spread of tick-acaricide control failure. Other sub-optimal tick control practices encountered included incorrect acaricide rotation, and failure to treat all cattle in a herd. This data will inform and guide the development of management strategies for tick-acaricide control failure and resistance in communal farming areas., (© 2024. The Author(s).)

The aim of this work was to analyze the R. microplus (Canestrini, 1888) infestation in two bovine herds with different degrees of natural resistance (i.e., Hereford and Braford) to ticks subjected to an identical chemical treatment scheme to ticks at the same farm, to demonstrate the impact on tick control of the incorporation of a more resistant bovine breed. Two groups of ten Hereford and Braford cows each were subjected to eleven chemical treatments between August 2022 and October 2023 (four fluazuron, two fipronil 1%, one ivermectin 3.15% and four immersion in a dipping vat with a combination of cypermethrin 10% and ethion 40%). Tick population was shown to be susceptible to ivermectin, fluazuron and the mix cypermethrin 10%-ethion 40% and resistant to fipronil according to in vitro tests. Tick infestation was significantly greater in the Hereford cows than in the Braford cows. Tick infestation in both Hereford and Braford breeds was similar when treatment with functional drugs was applied, but when a block of the treatments was done with drugs with decreased functionality due to resistance (i.e. fipronil), treatment failure was manifested more strongly in the most susceptible breed. The incorporation of cattle breeds with moderate or high resistance to R. microplus is instrumental to optimize the efficacy and sustainability of chemical control of ticks in a scenario where resistance to one or more chemical groups is almost ubiquitous, because it favors the biological control of this parasite., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Acaricides are the most widely used method to control the cattle tick Rhipicephalus microplus . However, its use increases production costs, contaminates food and the environment, and directly affects animal and human health. The intensive use of chemical control has resulted in the selection of genes associated with resistance to acaricides, and consumers are increasingly less tolerant of food contamination. This scenario has increased the interest of different research groups around the world for anti-tick vaccine development, in order to reduce the environmental impact, the presence of residues in food, and the harmful effects on animal and human health. There is enough evidence that vaccination with tick antigens induces protection against tick infestations, reducing tick populations and acaricide treatments. Despite the need for an anti-tick vaccine in Mexico, vaccination against ticks has been limited to one vaccine that is used in some regions. The aim of this review is to contribute to the discussion on tick control issues and provide a reference for readers interested in the importance of using anti-tick vaccines encouraging concerted action on the part of Mexican animal health authorities, livestock organizations, cattle producers, and academics. Therefore, it is suggested that an anti-tick vaccine should be included as a part of an integrated tick management program in Mexico.

Background: Rhipicephalus (Boophilus) microplus (Canestrini, 1888), the Asian blue tick, is a highly invasive and adaptable ectoparasite. This tick species has successfully established itself in most regions of the world, with movement of cattle being a major driver for its spread. In the recent past, R. microplus ticks have been reported in three districts of Uganda. Information on its spread and distribution are vital in deepening our understanding of the ecological scenarios that lead to tick persistence and in the formulation of control strategies. This is especially important in the cattle-dense districts., Methods: We randomly collected tick specimens from 1,461cattle spread across seven cattle dense districts located in the Central, Karamoja and West Nile regions of Uganda from January to September 2020. The ticks were identified using standard morpho-taxonomic keys and the R. microplus tick species identities were confirmed by sequencing of the ITS2 region, 12S rRNA and 16S rRNA genes and phylogenetic analyses., Results: Adult ticks (n = 13,019) were collected from 1,461 cattle. Seventeen tick species were identified based on morpho-taxonomic keys and the majority (47.4%; n=6184) of these were R. appendiculatus. In total, 257 R. microplus ticks were found infesting cattle in 18 study sites in the districts of Amudat, Kaabong, Napak (Karamoja region) and Arua (West Nile region). The identity of R. microplus was confirmed using molecular technics. No R. microplus tick was recorded in the districts of Lyantonde and Nakaseke (Central region). Arua district accounted for 82.1% (n=211) of the R. microplus ticks recorded followed by Napak district at 16.3% (n=42), while Amudat and Kaabong districts accounted for 1.5% (n=4). Rhipicephalus microplus and R. decoloratus co-existed in 6 of the 13 study sites in Arua district, while in another 6 study sites, no R. decoloratus was recorded. In the Karamoja region districts R. decoloratus co-existed with R.microplus. Of the total 618 ticks belonging to four species of the subgenus Boophilus recorded in this study, R. decoloratus accounted for 50.04% (n=334), followed by R. microplus at 41.58% (n=257), R. geigyi at 2.75% (n=17) and R. annulatus at 1.61% (n=10). In the districts of Amudat, Kaabong and Napak, R. decoloratus was more dominant (76.1%; n=179) of the three Rhipicephalus (Boophilus) tick species recorded, followed by R. microplus (19.5%; n=46) and R. geigyi (4.2%; n=10). Contrariwise, R. microplus was more dominant (84%; n=211) in Arua district followed by R. decoloratus (10.7%; n=27), R. annulatus (3.9%; n=10) and R. geigyi (1.1%; n=3). Phylogenetic analyses of the ITS2 region, 12S rRNA and 16S rRNA genes revealed subgrouping of the obtained sequences with the previously published R. microplus sequences from other parts of the world., Conclusion: Rhipicephalus microplus ticks were found infesting cattle in four districts of Uganda. The inability to find R. decoloratus, an indigenous tick, from six sites in the district of Arua is suggestive of its replacement by R. microplus. Rhipicephalus microplus negatively affects livestock production, and therefore, there is a need to determine its distribution and to deepen the understanding of the ecological factors that lead to its spread and persistence in an area., (© 2024. The Author(s).)

Medically important ixodid ticks often carry multiple pathogens, with individual ticks frequently coinfected and capable of transmitting multiple infections to hosts, including humans. Acquisition of multiple zoonotic pathogens by immature blacklegged ticks ( Ixodes scapularis ) is facilitated when they feed on small mammals, which are the most competent reservoir hosts for Anaplasma phagocytophilum (which causes anaplasmosis in humans), Babesia microti (babesiosis) and Borrelia burgdorferi (Lyme disease). Here, we used data from a large-scale, long-term experiment to ask whether patterns of single and multiple infections in questing nymphal I. scapularis ticks from residential neighbourhoods differed from those predicted by independent assortment of pathogens, and whether patterns of coinfection were affected by residential application of commercial acaricidal products. Quantitative polymerase chain reaction was used for pathogen detection in multiplex reactions. In control neighbourhoods and those treated with a fungus-based biopesticide deployed against host-seeking ticks (Met52), ticks having only single infections of either B. microti or B. burgdorferi were significantly less common than expected, whereas coinfections with these 2 pathogens were significantly more common. However, use of tick control system bait boxes, which kill ticks attempting to feed on small mammals, eliminated the bias towards coinfection. Although aimed at reducing the abundance of host-seeking ticks, control methods directed at ticks attached to small mammals may influence human exposure to coinfected ticks and the probability of exposure to multiple tick-borne infections.

Established tick control strategies often involve methods that can be damaging to existing environmental conditions or natural host ecology. To find more environmentally friendly methods, biological controls, like predators of ticks, have been suggested. There are natural predators of ticks, but most are generalists and not expected to control tick populations. Helmeted guinea fowl (Numida meleagris (L.) (Galliformes: Numididae)) have been suggested to be biological controls of ticks, and therefore, tick-borne pathogens, but their potential role as hosts for ticks complicates the relationship. A study was conducted to assess whether guinea fowl reduces the abundance of lone star ticks, Amblyomma americanum (L.) (Acari: Ixodidae), or whether they are hosts of ticks. Using mark-recapture techniques, painted lone star ticks were placed into 3 different treatments: penned, excluded, and free range. The recapture rates of painted ticks were compared. There was a significant difference between excluded and free-range treatments, but not between excluded and penned or between free range and penned. To investigate the role of guinea fowl as hosts of ticks, coop floors were examined for engorged ticks. Engorged lone star nymphs that had fed on guinea fowl were found. Lastly, ticks collected were tested to identify the potential reduction in risk of tick-borne pathogens. This study found no evidence that guinea fowl are an effective biological control of lone star ticks or tick-borne pathogens, but they are hosts of lone star nymphs. Future studies are needed to assess the complex ecology of a biological control of ticks that is also a host., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Evolutionary Biology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: In 2022, fluralaner was launched on the market for use in the control of the cattle tick Rhipicephalus microplus after showing 100% efficacy in registration trials against the causative agents of cattle tick fever (TFAs). The aim of the present study was to determine whether a strategic control regimen against R. microplus using fluralaner (FLU) in Holstein calves grazing in a tropical region would alter the enzootic stability status of cattle tick fever, triggering outbreaks in these animals up to 22 months age., Methods: In this study, a group of calves treated with FLU was compared with a control group treated with the regimen currently being used on the farm, which consisted of the fipronil + fluazuron formulation (FIFLUA). In the first experiment, the efficacy of the FIFLUA pour-on formulation was evaluated in a field study. In the second experiment, which lasted 550 days, two experimental groups (n = 30/group) of Holstein calves naturally infested with R. microplus were analyzed. Calves aged 4 to 10 months received either a specific treatment regimen with FLU (experimental group) or FIFLUA (control group). During this period, tick counts, animal weight measurement, feces collection (to determine eggs and oocysts per gram of feces), tick fever monitoring, blood smears (to ascertain enzootic stability of the herd), PCR testing for TFAs and serology (indirect enzyme-linked immunosorbent assay [iELISA]) were performed. All calves were evaluated for signs of tick fever between ages 11 and 22 months., Results: FIFLUA showed an acaricidal efficacy of > 90% from post-treatment days 14 to 35. Regarding treatments against the TFAs, the average number of treatments was similar between groups, but animals treated with FLU had a smaller reduction in packed cell volume on some of the evaluation dates of the second and third treatment against TFAs. In calves aged 10 months in the FLU group, B. bovis was not detected by PCR (0/15 samples), 40% of the samples had antibody titers and 33% (10/30) of the samples had positive blood smears. Regarding B. bigemina, > 86% of the samples in both groups tested positive for B. bigemina DNA and antibodies; there was no difference in the antibody titers between the groups. There were no clinical cases of cattle tick fever in calves aged 11 to 22 months., Conclusions: In comparison with the control treatment, the strategic control regimen against R. microplus with FLU that was implemented in the present study did not negatively affect the enzootic stability status of A. marginale and B. bigemina in the herd up to 22 months of age. The enzootic stability status of B. bovis was not reached by either group. These results likely represent a characteristic of the local tick population, so further studies should be performed., (© 2024. The Author(s).)

Background: Glutathione S-transferases (GSTs) are a superfamily of multifunctional enzymes in living organisms with metabolic and detoxification functions, which can detoxify exogenous and endogenous compounds and thereby reduce the damage caused by toxic substances to the body. Ticks are obligate blood-sucking ectoparasites that can transmit various pathogens, and the characterization of tick-derived GSTs may help improve current understanding of the molecular mechanism of tick resistance to insecticides. In this study, a novel GST gene, named HrGSTm1, was identified from Hyalomma rufipes., Methods: Sequence analysis was performed by using bioinformatics techniques. A prokaryotic expression system was used to obtain the recombinant expression protein rHrGSTm1. Detection of spatiotemporal expression patterns of target genes and their response to the toxicity of cyhalothrin on female H. rufipes was performed by using a quantitative PCR platform. The optimal enzymological parameters of rHrGSTm1 using glutathione as substrate were calculated. The antioxidant capacity of the recombinant protein was evaluated by DPPH• (1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl). Knockdown of the HrGSTm1 genes through RNA interference was used to analyze their effects on the physiological parameters of ticks. The changes in HrGSTm1 messenger RNA expression patterns under cypermethrin stress were analyzed., Results: The complementary DNA sequence of HrGSTm1 contained a 672-bp open reading frame, which potentially encoded 223 amino acids. The predicted molecular weight was 25.62 kDa, and the isoelectric point 8.22. HrGSTm1 is a Mu-class GST, belonging to the cytoplasmic GSTs with no signal peptide observed. The V max and K m of rHrGSTm1 were 3.367 ± 0.81 uM and 2.208 ± 0.76 uM, respectively, and its activities were dependent on different temperatures and pH conditions; the scavenging rate of rHrGSTm1 to DPPH• reached 76.4% at 1.25 mg/ml. Variable expressions of HrGSTm1 were observed under various treatment periods and in different tissues, with the highest appearing in eggs (analysis of variance [ANOVA], F (2, 9)  = 279.9, P < 0.0001) and Malpighian tubules (ANOVA, F (3, 12)  = 290.5, P < 0.0001). After knockdown of HrGSTm1, compared with the control group, the mortality in the treatment group was increased by 16.7%, the average oviposition rate decreased by 33.9%, the average engorged body weight decreased by 287.38 mg and egg weight decreased by 127.46 mg, although only the engorged body weight was significantly different (t-test, t (44)  = 2.886, P = 0.006). After exposure to three sublethal concentrations (LC 05 , LC 10 , LC 50 ) of cyhalothrin, the expression level of HrGSTm1 in the midgut, ovary and salivary gland was upregulated, whereas in Malpighian tubules, it showed a trend of upregulation at first and then downregulation, implying different functions during the detoxification in different tissues., Conclusions: In this study, a novel GST of the Mu-class was successfully isolated from H. rufipes and systematically subjected to bioinformatic analysis and recombination identification. The variation trend of HrGSTm1 expression level in different tissues suggests that the gene has different detoxification functions in different tissues. The potential function of this gene was analyzed to provide basic research for further investigation of its detoxification mechanism., (© 2023. The Author(s).)

Context: In the northeastern United States, recommendations to prevent diseases spread by black-legged ticks ( Ixodes scapularis ) and lone star ticks ( Amblyomma americanum ) often rely on individuals to use personal protection or yard-based strategies. The 4-Poster deer treatment stations (4-Posters) suppress tick populations by treating deer hosts with acaricide, potentially offering a community-wide approach for reducing tick-borne diseases in endemic areas. The 4-Poster deployment logistics in mainland community settings are not well documented but are needed for future public health tick control efforts., Program: As part of a public health research effort to design a population-based 4-Poster effectiveness study aimed at reducing tick-borne disease incidence, TickNET researchers partnered with the Town of Ridgefield (Connecticut) to understand the feasibility and operational logistics of deploying 4-Posters on public land within a residential community to inform future public health interventions by municipalities or vector control agencies., Implementation: We deployed three 4-Posters on a municipal property from July to December 2020 and used motion-activated cameras to record wildlife activity nearby. We documented per-device operational details, costs, materials consumed, and animal activity., Evaluation: Operation of 4-Posters was feasible, and device challenges were easily remedied. Deer visitation and heavy nontarget animal use were documented at all devices. Unexpectedly, monthly corn consumption was not correlated with monthly deer-view days. The monthly cost per device was US $1279 or US $305 per hectare with an average 21 minutes of weekly service time., Discussion: Use of 4-Posters by communities, public health agencies, or vector control programs may be a practicable addition to tick management programs in tick-borne disease endemic areas in the Northeast. Such programs should carefully consider local and state regulations, follow manufacturer and pesticide label guidelines, and include wildlife monitoring. High labor costs incurred in this project could be mitigated by training vector control agency or municipality staff to service 4-Posters., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Compliant ectoparasiticide product use is a comprehensive way to control ticks and reduce the risk of tick-borne pathogen transmission to dogs. Because the systemically acting isoxazoline ectoparasiticides require tick attachment for drug delivery, fast speed of kill is essential to minimize tick-borne pathogen transmission risk., Methods: Dogs of satisfactory tick-carrying capacity were randomly allocated to treatment groups and administered, per label instructions, Bravecto ® Chews (minimum 25 mg/kg fluralaner), Simparica TRIO ® (minimum 1.2 mg/kg sarolaner, 24 µg/kg moxidectin, 5 mg/kg pyrantel), or no treatment. Dogs were infested with approximately 50 unfed adult (35 female, 15 male) Ixodes scapularis on Day -2, 21 and 28. Live tick counts were performed at 4, 8, 12 and 24 h post-treatment (Day 0) and post-infestation on Day 21 and 28. Tick control efficacy was determined by comparing live tick means for each product-treated group to the untreated control group and each other at all time points using a linear mixed model. The percent of dogs free of live ticks was analyzed using the Fisher's exact test for treatment group comparison., Results: The untreated control group maintained adequate tick infestations throughout the study. Using geometric means, an existing I. scapularis infestation was controlled by 99.7% and 93.0% 12 h post-treatment and by 100% and 99.5% 24 h post-treatment, for Bravecto ® and Simparica TRIO ® -treated dogs, respectively. Ixodes scapularis infestations were controlled more quickly for Bravecto ® - compared to Simparica TRIO ® -treated dogs on Day 21 at 8 h (efficacy 74.0% vs. 0.0%, p = 0.003) and 12 h (efficacy 99.2% vs. 39.4%, p < 0.001) post-infestation and Day 28 at 8 h (efficacy 92.2% vs. 0.0%, p < 0.001) and 12 h (efficacy 99.6% vs. 27.7%, p < 0.001) post-infestation. On Day 28 post-treatment, the efficacy of Bravecto ® and Simparica TRIO ® to control a new I. scapularis infestation was 100% and 96.6%, respectively, by 24 h post-infestation. Of product-treated dogs, 100% of Bravecto ® -treated dogs were free of live ticks by 24 h post-treatment or post-infestation. No treatment-related adverse reactions occurred during the study., Conclusions: Ixodes scapularis infestations are controlled more quickly 21 and 28 days post-treatment for dogs administered a single dose of Bravecto ® compared to dogs administered a single dose of Simparica TRIO ® ., (© 2023. The Author(s).)

The control of ticks through vaccination offers a sustainable alternative to the use of chemicals that cause contamination and the selection of resistant tick strains. However, only a limited number of anti-tick vaccines have reached commercial realization. In this sense, an antigen effective against different tick species is a desirable target for developing such vaccines. A peptide derived from the tick P0 protein (pP0) conjugated to a carrier protein has been demonstrated to be effective against the Rhipicephalus microplus, Rhipicephalus sanguineus , and Amblyomma mixtum tick species. The aim of this work was to assess the efficacy of this peptide when conjugated to the Bm86 protein against Dermacentor nitens and Ixodes ricinus ticks. An RNAi experiment using P0 dsRNA from I. ricinus showed a dramatic reduction in the feeding of injected female ticks on guinea pigs. In the follow-up vaccination experiments, rabbits were immunized with the pP0-Bm86 conjugate and challenged simultaneously with larvae, nymphs, and the adults of I. ricinus ticks. In the same way, horses were immunized with the pP0-Bm86 conjugate and challenged with D. nitens larva. The pP0-Bm86 conjugate showed efficacies of 63% and 55% against I. ricinus and D. nitens ticks, respectively. These results, combined with previous reports of efficacy for this conjugate, show the promising potential for its development as a broad-spectrum anti-tick vaccine.

Background: Tick control is a worldwide challenge due to its resistance to acaricides. Essential oils (EOs) and isolated compounds (EOCs) are potential alternatives for tick control technologies., Methods: A review with EOs and EOCs, under field and semi-field conditions, was performed based on Scopus, Web of Science and PubMed databases. Thirty-one studies published between 1991 and 2022 were selected. The search was performed using the following keywords: "essential oil" combined with "tick," "Ixodes," "Argas," "Rhipicephalus," "Amblyomma," "Hyalomma," "Dermacentor," "Haemaphysalis" and "Ornithodoros." The words "essential oil" and "tick" were searched in the singular and plural., Results: The number of studies increased over the years. Brazil stands out with the largest number (51.6%) of publications. The most studied tick species were Rhipicephalus microplus (48.4%), Ixodes scapularis (19.4%), Amblyomma americanum and R. sanguineus sensu lato (9.7% each). Cattle (70%) and dogs (13%) were the main target animal species. Regarding the application of EOs/EOCs formulations, 74% of the studies were conducted with topical application (spray, pour-on, foam, drop) and 26% with environmental treatment (spray). Efficacy results are difficult to evaluate because of the lack of information on the methodology and standardization. The nanotechnology and combination with synthetic acaricides were reported as an alternative to enhance the efficacy of EOs/EOCs. No adverse reactions were observed in 86.6% of the studies evaluating EOs/EOCs clinical safety. Studies regarding toxicity in non-target species and residues are scarce., Conclusions: This article provides a comprehensive review on the use of EOs and EOCs to reduce tick infestations, in both the hosts and the environment. As future directions, we recommend the chemical characterization of EOs, methodology standardization, combination of EOs/EOCs with potential synergists, nanotechnology for new formulations and safety studies for target and non-target organisms, also considering the environmental friendliness., (© 2023. The Author(s).)

The objective of this work was to characterize the Argentine Creole cattle breed through the identification of individual phenotypic variations in the levels of infestation with Rhipicephalus (Boophilus) microplus. We evaluated 179 heifers exposed to successive artificial infestations from 2015 to 2018, achieving a total of 663 observations. Tick counts were assessed with the linear mixed model, considering year of evaluation, time of infestation, dam's age and nutritional status during the evaluated period as fixed effects. The average tick count value obtained allowed to classify the breed as highly resistant to the tick charge (99.3%). Although the previous nutritional condition of the animals did not affect the individual charge response, weight gain during the trial showed a significantly negative correlation. We conclude that the Argentine Creole breed is an attractive genetic alternative for cattle breeding in endemic regions, either as a pure breed or a cross-breed., Competing Interests: Declaration of Competing Interest The authors declare no conflicts of interest., (Copyright © 2023 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

The 4-Poster Tick Control Deer Feeder (4-poster) device applies acaricide to white-tailed deer (Odocoileus virginianus) and can reduce populations of the blacklegged tick (Ixodes scapularis), which transmits the agents of Lyme disease, anaplasmosis, babesiosis, and Powassan virus disease in the Northeastern United States. While 4-poster devices have the potential to provide community-wide management of blacklegged ticks in Lyme disease endemic areas, no recent study has assessed their acceptability among residents. We conducted a survey of residents from 16 counties with high annual average Lyme disease incidence (≥ 10 cases per 100,000 persons between 2013 and 2017) in Connecticut and New York to understand perceptions and experiences related to tickborne diseases, support or concerns for placement of 4-poster devices in their community, and opinions on which entities should be responsible for tick control on private properties. Overall, 37% of 1652 respondents (5.5% response rate) would support placement of a 4-poster device on their own property, 71% would support placement on other private land in their community, and 90% would support placement on public land. Respondents who were male, rented their property, resided on larger properties, or were very or extremely concerned about encountering ticks on their property were each more likely to support placement of 4-poster devices on their own property. The primary reason for not supporting placement of a 4-poster device on one's own property was the need for weekly service visits from pest control professionals, whereas the top reason for not supporting placement on other land (private or public) was safety concerns. Most respondents (61%) felt property owners should be responsible for tick control on private properties. Communities considering 4-poster devices as part of a tick management strategy should consider targeting owners of larger properties and placing devices on public lands., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023. Published by Elsevier GmbH.)

Control of complex parasites via vaccination remains challenging, with the current combination of vaccines and small drugs remaining the choice for an integrated control strategy. Studies conducted to date, are providing evidence that multicomponent vaccines will be needed for the development of protective vaccines against endo- and ectoparasites, though multicomponent vaccines require an in-depth understanding of parasite biology which remains insufficient for ticks. With the rapid development and spread of acaricide resistance in ticks, new targets for acaricide development also remains to be identified, along with novel targets that can be exploited for the design of lead compounds. In this study, we analysed the differential gene expression of Rhipicephalus microplus ticks that were fed on cattle vaccinated with a multi-component vaccine (Bm86 and 3 putative Bm86-binding proteins). The data was scrutinised for the identification of vaccine targets, small drug targets and novel pathways that can be evaluated in future studies. Limitations associated with targeting novel proteins for vaccine and/or drug design is also discussed and placed into the context of challenges arising when targeting large protein families and intracellular localised proteins. Lastly, this study provide insight into how Bm86-based vaccines may reduce successful uptake and digestion of the bloodmeal and overall tick fecundity., (© 2023. The Author(s).)

Mites have been a persistent infectious disease affecting both humans and animals since ancient times. In veterinary clinics, the primary approach for treating and managing mite infestations has long been the use of chemical acaricides. However, the widespread use of these chemicals has resulted in significant problems, including drug resistance, drug residues, and environmental pollution, limiting their effectiveness. To address these challenges, researchers have shifted their focus towards natural products that have shown promise both in the laboratory and real-world settings against mite infestations. Natural products have a wide variety of chemical structures and biological activities, including acaricidal properties. This article offers a comprehensive review of the acaricidal capabilities and mechanisms of action of natural products like plant extracts, natural compounds, algae, and microbial metabolites against common animal mites.

We evaluated the relative effectiveness of the natural product acaricide Essentria IC3 and the entomopathogenic fungal acaricide BotaniGard ES to suppress host-seeking Ixodes scapularis Say and Amblyomma americanum (L.) nymphs when applied with low-pressure backpack and high-pressure sprayers. Essentria IC3 applied by backpack sprayer out-performed high-pressure applications, while the opposite was true for treatments with BotaniGard ES. We were unable to demonstrate consistently greater efficacy using high-pressure applications, and neither of the acaricides or application methods provided substantial (>90%) levels of control at 7 days postapplication., (© The Author(s) 2023. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Purpose: Pastoralists regularly come in contact with ticks as they herd their animals and are exposed to pathogens that cause zoonotic diseases. No study has been conducted in Nigeria to evaluate the knowledge, attitudes, and practices (KAP) of these Pastoralists towards ticks, tick bite, and tick control, and thus this research., Methods: A KAP survey of pastoralists (n = 119) was conducted in Plateau State, Nigeria. Data generated were analysed using Statistical Package for Social Sciences (SPSS)., Results: The majority of the pastoralists (99.2%) had knowledge of ticks, with 79% of them being aware that ticks attach and bite humans, whereas only 30.3% believed that ticks transmit diseases to humans. Eighty-four per cent of the pastoralists do not wear protective clothing while herding their animals and 81.5% indicated to having been bitten by ticks, whereas hospital visit after tick bite was low (7.6%). Statistically significant variables were observed when knowledge of the respondents were compared in relation to the ability of ticks to cause diseases (Χ 2  = 9.980, P = 0.007); hospital visit after a bite (Χ 2  = 11.453, P = 0.003); and the use of protective clothing for herding (Χ 2  = 22.596, P = 0). The main tick control measure was hand picking (58.8%)., Conclusions: The pastoralists were unaware of the ability of ticks to transmit zoonotic pathogens. Preventive practices were insufficient to reduce tick bites, and thus were constantly exposed to tick-borne diseases. This study hopes to provide important insights for the development of educational awareness programmes for the pastoralists and serve as a guide for the health workers in designing future preventive programmes against tick-borne zoonoses in Nigeria., (© 2023. The Author(s) under exclusive licence to Witold Stefański Institute of Parasitology, Polish Academy of Sciences.)

Rhipicephalus microplus is the main ectoparasite of cattle and its parasitism can reduce weight gain of hosts, in addition to causing anemia, increasing the risk of myiasis, and resulting in the transmission of Babesia bovis and Anaplasma marginale, among other pathogens. The use of synthetic chemicals plays an important role in controlling these ticks. However, its frequent and indiscriminate use has contributed to the selection of resistant strains, resulting in greater interest in the search for natural-origin products. The shrub Callistemon viminalis (Myrtaceae), also known as weeping bottlebrush, is known for its antibacterial, acaricidal, repellent, and antifungal activities, but there are no reports in the literature about its effects on the internal morphology of ticks. This study aimed to extract and characterize the essential oil obtained from the leaves of C. viminalis. Additionally, its effects on the ovary morphology of engorged R. microplus were assessed through histological, histochemical, and morphometric techniques. Exposure to C. viminalis caused dose-dependent morphological changes, such as cellular alterations in the epithelial layer lining the ovary lumen and the pedicel, irregularity of the chorion and oocyte shape, changes in protein and carbohydrate content, decrease in oocyte size, reduction in the size of the nucleus as well as cytoplasmic and nucleolar vacuolation. Thus, C. viminalis essential oil exhibited a toxic effect on the reproductive system of R. microplus, which may result in the reproductive impairment of this tick species., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Nanoformulations containing zein nanoparticles (ZN) can promote the stability and protection of molecules with acaricidal activity. The present study sought to develop nanoformulations with ZN associated with cypermethrin (CYPE) + chlorpyrifos (CHLO) + a plant compound (citral, menthol or limonene), characterize them, and verify their efficacy against Rhipicephalus microplus ticks. Additionally, we aimed to assess its safety in nontarget nematodes found in soil at a site subjected to contamination by acaricides. The nanoformulations were characterized by dynamic light scattering and nanoparticle tracking analysis. Nanoformulations 1 (ZN+CYPE+CHLO+citral), 2 (ZN+CYPE+CHLO+menthol), and 3 (ZN+CYPE+CHLO+limonene) were measured for diameter, polydispersion, zeta potential, concentration, and encapsulation efficiency. Nanoformulations 1, 2, and 3 were evaluated in a range from 0.004 to 0.466 mg/mL on R. microplus larvae and caused mortality > 80% at concentrations above 0.029 mg/mL. The commercial acaricide Colosso® (CYPE 15 g + CHLO 25 g + citronellal 1 g) was evaluated also from 0.004 to 0.512 mg/mL and resulted in 71.9% larval mortality at 0.064 mg/mL. Formulations 1, 2, and 3 at 0.466 mg/mL showed acaricidal efficacy of 50.2%, 40.5%, and 60.1% on engorged females, respectively, while Colosso® at 0.512 mg/mL obtained only 39.4%. The nanoformulations exhibited long residual period of activity and lower toxicity to nontarget nematodes. ZN was able to protect the active compounds against degradation during the storage period. Thus, ZN can be an alternative for the development of new acaricidal formulations using lower concentrations of active compounds., Competing Interests: Declaration of Competing Interest The authors warrant that there are no any conflicts of interests among authors and between authors and other people, institutions or organizations., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Controlling the abundance of blacklegged ticks is considered the foundation for the prevention of human exposure to pathogens transmitted by these vectors in eastern North America. The use of broadcast or host-targeted acaricides is generally found to be effective at reducing the local abundance of ticks. However, studies that incorporate randomization, placebo controls, and masking, i.e., "blinding", generally find lower efficacy. The few studies that include measurements of human-tick encounters and cases of tickborne disease have not shown impacts of acaricidal treatments. We compile literature on relevant studies from northeastern North America to address possible causes for discrepancies in study outcomes and suggest possible mechanisms that could underlie the diminished efficacy of tick control in reducing cases of tickborne disease in people.

Acaricide resistance is a global problem that has impacts worldwide. Tick populations with broad resistance to all commercially available acaricides have been reported. Since resistance selection in ticks and their role in pathogen transmission to animals and humans result in important economic and public health burden, it is essential to develop new strategies for their control (i.e., novel chemical compounds, vaccines, biological control). The synganglion is the tick central nervous system and it is responsible for synthesizing and releasing signaling molecules with different physiological functions. Synganglion proteins are the targets of the majority of available acaricides. In this review we provide an overview of the mode-of-action and resistance mechanisms against neurotoxic acaricides in ticks, as well as putative target sites in synganglion, as a supporting tool to identify new target proteins and to develop new strategies for tick control., Competing Interests: Declarations of Competing Interest None., (Copyright © 2023 The Author(s). Published by Elsevier GmbH.. All rights reserved.)

In the United States, tick-borne diseases (TBDs) are a major public health concern and a source of significant morbidity. To reduce tick-borne disease incidence, understanding factors associated with increased risk in humans for tick bites is necessary. These risk factors can include TBD knowledge, attitudes about prevention and care, and associated practices of individuals and their communities, including paying for preventive services. Our study focused on Long Island, New York, a region with high endemicity of ticks and TBDs. The purpose of our study was to identify gaps in the knowledge, attitudes, and practices regarding TBDs in residents of this region to inform priorities for TBD interventions. To this end, we performed a knowledge, attitudes, and practices (KAP) survey and collected 803 responses from Long Island residents. Our survey results demonstrated that Long Island residents had a low to moderate level of knowledge regarding ticks and TBDs. Still, residents expressed concern regarding TBDs, with increased levels of concern associated with increased likelihood of paying for tick control and for practicing tick bite prevention strategies. Individuals with pets were more likely to practice these tick bite prevention strategies. Residents with more frequent exposure to ticks, with a history of TBD in their household, and with higher general concern over ticks were also more likely to pay for tick control services. These findings highlight gaps in resident knowledge, differences in attitudes towards tick preventative behavior, and potential factors affecting motivation towards implementing tick control measures, which can inform future public health messaging regarding tick bite prevention., (Copyright © 2023. Published by Elsevier GmbH.)

Ticks can seriously affect human and animal health around the globe, causing significant economic losses each year. Chemical acaricides are widely used to control ticks, which negatively impact the environment and result in the emergence of acaricide-resistant tick populations. A vaccine is considered as one of the best alternative approaches to control ticks and tick-borne diseases, as it is less expensive and more effective than chemical controls. Many antigen-based vaccines have been developed as a result of current advances in transcriptomics, genomics, and proteomic techniques. A few of these (e.g., Gavac ® and TickGARD ® ) are commercially available and are commonly used in different countries. Furthermore, a significant number of novel antigens are being investigated with the perspective of developing new anti-tick vaccines. However, more research is required to develop new and more efficient antigen-based vaccines, including on assessing the efficiency of various epitopes against different tick species to confirm their cross-reactivity and their high immunogenicity. In this review, we discuss the recent advancements in the development of antigen-based vaccines (traditional and RNA-based) and provide a brief overview of recent discoveries of novel antigens, along with their sources, characteristics, and the methods used to test their efficiency.

Anti-tick vaccines development mainly depends on the identification of suitable antigens, which ideally should have different features. These should be key molecules in tick biology, encoded by a single gene, expressed across life stages and tick tissues, capable of inducing B and T cells to promote an immunological response without allergenic, hemolytic, and toxic effects; and should not be homologous to the mammalian host. The discussion regarding this subject and the usefulness of "exposed" and "concealed" antigens was effectively explored in the publication by Nuttall et al. (2006). The present commentary intends to debate the relevance of such study in the field of tick immunological control.

Acaricides are hypothesized to reduce human risk of exposure to tick-borne pathogens by decreasing the abundance and/or infection prevalence of the ticks that serve as vectors for the pathogens. Acaricides targeted at reservoir hosts such as small mammals are expected to reduce infection prevalence in ticks by preventing their acquisition of zoonotic pathogens. By reducing tick abundance, reservoir-targeted or broadcast acaricides could reduce tick infection prevalence by interrupting transmission cycles between ticks and their hosts. Using an acaricide targeted at small-mammal hosts (TCS bait boxes) and one sprayed on low vegetation (Met52 fungal biocide), we tested the hypotheses that infection prevalence of blacklegged ticks with zoonotic pathogens would be more strongly diminished by TCS bait boxes, and that any effects of both acaricidal treatments would increase during the four years of deployment. We used a masked, placebo-controlled design in 24 residential neighborhoods in Dutchess County, New York. Analyzing prevalence of infection with Borrelia burgdorferi , Anaplasma phagocytophilum , and Babesia microti in 5380 nymphal Ixodes scapularis ticks, we found little support for either hypothesis. TCS bait boxes did not reduce infection prevalence with any of the three pathogens compared to placebo controls. Met52 was associated with lower infection prevalence with B. burgdorferi compared to placebo controls but had no effect on prevalence of infection with the other two pathogens. Although significant effects of year on infection prevalence of all three pathogens were detected, hypothesized cumulative reductions in prevalence were observed only for B. burgdorferi . We conclude that reservoir-targeted and broadcast acaricides might not generally disrupt pathogen transmission between reservoir hosts and tick vectors or reduce human risk of exposure to tick-borne pathogens.

Nuisance and medically important ticks can be abundant in a variety of forested landscapes, including recreational parks. Strategies to reduce the abundance of host-seeking ticks in high-use areas within parks are limited. Mowing vegetation is a recommended method to control ticks, but few studies have evaluated the efficacy of this practice. The goal of this study was to determine if a single mowing event could reduce the abundance of host-seeking ticks on recreational trails. Ticks were collected by dragging trails at three recreational parks in northern Minnesota during June and July, 2021. A pre-intervention sample was taken followed by six consecutive weeks of tick sampling. We encountered a total of 3,456 ticks (2,459 Ixodes scapularis Say and 997 Dermacentor variabilis L.) during the 7-week study period. There were no significant differences in the abundance of I. scapularis (adults) or D. variabilis (adults only) between control and mown trail sections. Mowing was a significant predictor of nymphal I. scapularis abundance but trended towards more ticks in mown sections compared to controls. These results suggest that a single mowing intervention during early June is likely to be ineffective as a strategy to reduce the risk of human contacts with ticks on trails., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Dermanyssus gallinae, also known as the poultry red mite (PRM), is one of widespread ectoparasite in the poultry industry worldwide, causing direct and indirect detriments to poultry as well as substantial financial losses. Novel control methods are urgently needed to improve the current acaricide-based control of D. gallinae. The control approach based on arrestment pheromone is environment-friendly but the related research is limited in PRMs. In the present study we found two compounds from the mite feces acting as arrestment pheromones of D. gallinae, which could lead to mite arrestment upon contact. One is guanine, which was also found in unfed female mites' acid-saline extract. The other is hematin. Moreover, it was found that the ferric ion of hematin played a pivotal role in stimulating the arrestment of mites. Finally, it was found the combination of guanine or/and hematin plus cypermethrin led to significantly improved mite-killing performance compared with cypermethrin, showing a promising potential of novel control method based on the arrestment pheromone., Competing Interests: Conflict of Interest The authors declared that they have no conflicts of interest to this work. We declare that none of the contents of this manuscript have been published or are under consideration for publication elsewhere and that no competing interests exist. All authors have contributed to read and approved this submitted manuscript in its current form., (Copyright © 2022 Elsevier B.V. All rights reserved.)

We used a spatially explicit model to simulate the potential effects of exclosures and acaricides targeted at medium-sized mammalian hosts on the local distribution and abundance of lone star ticks ( Amblyomma americanum ) within forestlands of the southeastern United States. Both exclosures and acaricides were successful in markedly reducing the densities of all off-host tick life stages inside the treatment areas. Densities dropped to almost zero immediately inside the edges of the exclosures, with noticeably depressed densities extending outward 30 to 60 m from the exclosures, and the simulated exclosures maintained their effectiveness as their sizes were decreased from 4.5 to 2.25 to 0.8 ha. Densities exhibited a smooth gradient across the edges of the acaricide-treated areas, with depressed densities extending ≈100 m outward from the edges, but with perceptible densities extending ≈60 m inward from the edges; thus, the simulated acaricide areas lost their effectiveness as size was decreased to slightly less than one-half the diameter of the activity range of the targeted host. Our simulation results indicated that off-host nymph densities responded to reductions of medium-sized host densities. These results suggest that targeting acaricides at medium-sized hosts may be an effective, and currently under-utilized, method for tick suppression.

Ticks are able to transmit the highest number of pathogen species of any blood-feeding arthropod and represent a growing threat to public health and agricultural systems worldwide. While there are numerous and varied causes and effects of changes to tick-borne disease (re)emergence, three primary challenges to tick control were identified in this review from a U.S. borders perspective. (1) Climate change is implicated in current and future alterations to geographic ranges and population densities of tick species, pathogens they can transmit, and their host and reservoir species, as highlighted by Ixodes scapularis and its expansion across southern Canada. (2) Modern technological advances have created an increasingly interconnected world, contributing to an increase in invasive tick species introductions through the increased speed and frequency of trade and travel. The introduction of the invasive Haemaphysalis longicornis in the eastern U.S. exemplifies the challenges with control in a highly interconnected world. (3) Lastly, while not a new challenge, differences in disease surveillance, control, and management strategies in bordering countries remains a critical challenge in managing ticks and tick-borne diseases. International inter-agency collaborations along the U.S.-Mexico border have been critical in control and mitigation of cattle fever ticks ( Rhipicephalus spp.) and highlight the need for continued collaboration and research into integrated tick management strategies. These case studies were used to identify challenges and opportunities for tick control and mitigation efforts through a One Health framework.