Prevention Of Tick-borne Diseases Research Articles

Tick-borne pathogens Ehrlichia, Hepatozoon, and Babesia co-infection in owned dogs in Central Thailand.

Tick-borne pathogens are transmitted by a wide range of tick species and affect both human and animal health. Understanding the diversity of these pathogens and their co-infection rates in domesticated animals in urban areas is crucial for effective disease management and prevention. In this study, a total of 565 owned dogs in the central region of Thailand were investigated for the infection rate of three genera of Ehrlichia, Hepatozoon, and Babesia infection using multiplex PCR. The results revealed an overall infection rate of 19.1%, with Ehrlichia having the highest infection rate (12.2%), followed by Babesia (2.5%) and Hepatozoon (1.4%). The rate of co-infection was 3%, with mixed infections involving two or three genera. Male dogs exhibited a slightly higher infection rate compared to females, although not statistically significant. Young adult dogs (1-3 years) showed the highest infection rate of both single infections and co-infections. Monthly infection rate indicated variations throughout the year, with co-infection rate significantly associated with overall infection rate. Clinical manifestations in three genera of infected dogs included thrombocytopenia and eosinopenia. The results of this study are useful to design strategies for the management and prevention of tick-borne diseases in the study area.

In vitro acaricidal activity of essential oils and their binary mixtures against ixodes scapularis (Acari: Ixodidae)

Ixodes scapularis ticks are vectors of infectious agents that cause illness in humans, including Lyme disease. Recent years have seen a surge in tick-borne diseases (TBD) resulting in a high demand for tick management products. Plants offer a valuable source of active compounds for the development of novel, eco-friendly tick control products, reducing potential risks to human and animal health. Essential oils (EOs) have emerged as potential acaricides and repellents against ticks providing an alternative to synthetic chemicals and aiding in the prevention of TBD by lowering the risk of tick bites. We investigated the acaricidal activity of EOs from lemongrass (Cymbopogon citratus), geranium (Pelargonium x asperum), savory thyme (Thymus saturejoides), and white thyme (Thymus zygis) on I. scapularis. The interactions (i.e., synergistic, antagonistic, or additive) of their binary mixtures were also evaluated. EO samples were analyzed via gas chromatography-mass spectrometry to determine their chemical composition. The adult immersion test was used to determine the lethal concentration (LC50) of each EO alone and in mixtures. Quantitative assessment of synergistic, additive, or antagonistic effect of the binary mixtures was performed by calculating the combination index. Strong acaricidal activity was recorded for savory thyme and white thyme EOs, with LC50 values of 28.0 and 11.0 μg/μL, respectively. The LC50 of lemongrass and geranium EOs were 49.0 and 39.7 μg/μL, respectively. Among the tested EOs, savory thyme and white thyme had a strong acaricidal effect on I. scapularis, which might be linked to the presence of carvacrol (26.05 % ± 0.38) and thymol (53.6 % ± 2.31), main components present in savory thyme and white thyme EOs, respectively. The tick killing efficacy of lemongrass and geranium EOs was lower when mixed than when used separately (LC50 of 65.3 µg/µL). The same happened with savory thyme and white thyme EOs, except at 9.75 µg/µL where they had a synergistic effect (LC50 of 58.3 µg/µL). Lemongrass and savory thyme EOs had a synergistic effect at low concentrations, and an antagonistic effect at higher concentrations (LC50 of 95.4 µg/µL). Lemongrass and white thyme EOs had a synergistic effect against ticks from 15 to 120 µg/µL (LC50 of 18.5 µg/µL) similar to white thyme EO. Geranium and savory thyme EOs had an antagonistic effect at all concentrations, with an LC50 of 66.8 µg/µL. Geranium and white thyme EOs also had an antagonistic effect, except at 12.7 µg/µL where they had a synergistic effect (LC50 of 66.8 µg/µL). The interaction observed when combining selected essential oils suggests promising potential for developing acaricidal formulations aimed at controlling ticks and curbing the transmission of tick-borne disease agents.

Assessing the Influence of Climate Change and Environmental Factors on the Top Tick-Borne Diseases in the United States: A Systematic Review.

In the United States (US), tick-borne diseases (TBDs) have more than doubled in the past fifteen years and are a major contributor to the overall burden of vector-borne diseases. The most common TBDs in the US-Lyme disease, rickettsioses (including Rocky Mountain spotted fever), and anaplasmosis-have gradually shifted in recent years, resulting in increased morbidity and mortality. In this systematic review, we examined climate change and other environmental factors that have influenced the epidemiology of these TBDs in the US while highlighting the opportunities for a One Health approach to mitigating their impact. We searched Medline Plus, PUBMED, and Google Scholar for studies focused on these three TBDs in the US from January 2018 to August 2023. Data selection and extraction were completed using Covidence, and the risk of bias was assessed with the ROBINS-I tool. The review included 84 papers covering multiple states across the US. We found that climate, seasonality and temporality, and land use are important environmental factors that impact the epidemiology and patterns of TBDs. The emerging trends, influenced by environmental factors, emphasize the need for region-specific research to aid in the prediction and prevention of TBDs.

An assessment of equine veterinarian knowledge and perceptions of ticks and tick‐borne diseases in the United States to inform continuing education needs

SummaryBackgroundTicks can harm horses and transmit diseases, making them a growing concern for owners and veterinarians. Veterinarians play a crucial role in providing advice on tick prevention and control. Yet, no research has examined their perspectives on equine ticks and tick‐borne disease (TBD).ObjectivesThe objective was to assess equine veterinarians' experiences, knowledge and practices related to fundamental aspects of tick biology and identification, tick bite prevention and TBD in the United States.Study designThis project surveyed equine veterinarians in the United States about their knowledge of ticks and TBD affecting horses using nonprobability convenience sampling. The survey questions were grouped into six categories: respondent demographics, knowledge of ticks and TBDs, tick control option availability, tick and TBD frequency in horses and veterinary education and information availability.MethodsData were analysed using descriptive statistics, chi‐square analysis and t‐tests. The sample was divided into Northeast and United States veterinarians, and a significance level of p < 0.05 was set. The study aimed to inform continuing education development for veterinarians by assessing their knowledge, practices and perceptions of ticks and TBDs.ResultsThe results indicate that while equine veterinarians know the importance of TBDs in equine health, knowledge on ticks and TBDs varies significantly.Main limitationsLimitations for the current study include potential response bias and a limited sample from many states.ConclusionsThere is a need for increased tick control and prevention options and more animal‐specific resources for tick and TBD prevention. Veterinarians and horse owners require greater education and comprehensive information to prevent tick‐borne illnesses in horses. Collaborations between academia, industry and the human medicine community are suggested to build capacity for training veterinarians.

Experimental infection and co-infection with Chinese strains of Ehrlichia canis and Babesia vogeli in intact and splenectomized dogs: Insights on clinical, hematologic and treatment responses

Animal infection models are crucial for studying various aspects of Ehrlichia canis infections. To understand the pathogenesis of the first Chinese isolate of E. canis and simulate the natural progression of canine ehrlichiosis, we developed a model with 18 Beagle dogs that consisted of E. canis initial infection (days 0–17), treatment with doxycycline or rifampicin (days 18–32), recovery (days 33–66), E. canis reinfection (days 67–91), and Babesia vogeli superinfection (days 92–116). We measured body weight and rectal temperature every other day, drew blood every 4 days for routine hematology and biochemistry tests, and for quantification of E. canis and B. vogeli by quantitative PCRs. In this study, the first isolate of E. canis from China was used to experimentally infect dogs, and the infected dogs exhibited clinical signs of acute severe ehrlichiosis, including high fever, loss of appetite, dehydration, and body weight loss, confirming the similar pathogenicity of E. canis in China as compared to isolates from other regions. Infection with E. canis and B. vogeli led to reduced body weight and fever in dogs. Doxycycline treatment led to absence of E. canis DNA in infected dogs, while rifampicin treatment lowered the blood E. canis copy number up to 1.5 folds. E. canis-free infected dogs after doxycycline treatment were successfully re-infected with E. canis, indicating dogs with antibodies are still at risk of re-infection. Super-infection with B. vogeli resulted in higher fever, more severe anemia, and a reduced number of platelets. Splenectomized dogs showed significantly higher E. canis numbers during recovery and re-infection than intact dogs. The histological changes were observed in brain, lung, kidney, liver and spleen of the infected dogs. The findings in this study provide insights into clinical and hematologic responses, as well as effective treatment options, for dogs infected with the first Chinese isolate of E. canis, and may contribute to our understanding of the diagnosis and prevention of tick-borne diseases in dogs, including canine monocytic ehrlichiosis.

Identifying Trusted Sources of Lyme Disease Prevention Information Among Internet Users Connected to Academic Public Health Resources: Internet-Based Survey Study.

Misinformation about Lyme disease and other tick-transmitted pathogens circulates frequently on the internet and can compete with, or even overshadow, science-based guidance on tick-borne disease (TBD) prevention. We surveyed internet users connected to academic tick-related resources to identify trusted sources of Lyme disease prevention information, explore confidence in tick bite prevention information, and examine associations of these responses with answers to commonly disputed issues. The survey was conducted through social media and website pages for Western Connecticut State University Tickborne Disease Prevention Laboratory and the University of Rhode Island TickEncounter Resource Center. Respondents (N=1190) were predominantly female (903/1190, 76.3%), middle-aged (574/1182, 48.6%), and resided in New England states (663/1190, 55.7%). In total 984 of 1186 (83%) respondents identified conventional experts (eg, the Centers for Disease Control [CDC] or other government health agencies, physicians who follow Infectious Diseases Society of America guidelines for Lyme disease treatment guidelines, and academics) as trustworthy TBD prevention resources. However, nearly one-fourth of respondents would first consult personal contacts and web-based communities regarding prevention information before consulting conventional expert sources. The opinions of public health experts and physicians were rated among the top motivators underlying personal prevention decisions; yet, more than 50% of participants revealed distrustful attitudes toward, or were uncertain about, CDC-supported statements related to time to transmission of Lyme disease (708/1190, 59.5%), the safety of diethyltoluamide-based repellents for children (604/1183, 51.1%), and recommended use of antibiotic prophylaxis (773/1181, 65.4%). Multimodal regression models revealed that participants from high-Lyme-disease-incidence states were more likely to first seek TBD prevention information from personal networks and nontraditional sources before approaching conventional sources of TBD prevention information. We found that those reporting high rates of social media usage were more than twice as likely to first seek traditional expert sources of prevention information but were overall more likely to reject CDC-promoted Lyme disease information, in particular the established time to transmission of Lyme disease bacteria. Models also predicted that those participants who disagreed with the conventional scientific view on the antibiotic prophylaxis prevention statement were less likely to be confident in their ability to protect themselves from a tick bite. Overall, uncertainty in one's ability to protect oneself against tick bites was strongly associated with uncertainty about beliefs in CDC-promoted TBD prevention information. Self-reported trust in experts and frequency of social media use suggest that these platforms may provide opportunities to engage directly with the public about TBD prevention practices. Using strategies to improve public trust and provide information where the public engages on social media may improve prevention communication and adoption of best practices.

Development and field evaluation of PCR assays based on minimum length Bm86 cDNA fragments required for Rhipicephalus and Hyalomma tick species delineation.

Hyalomma and Rhipicephalus ticks are important genera that can transmit diseases to both animals and humans, including Crimean-Congo hemorrhagic fever, tick-borne encephalitis, and several types of spotted fever. The accurate identification of tick species is essential for the effective control and prevention of tick-borne diseases. However, traditional identification methods based on morphology can be challenging and subjective, leading to errors. The development of DNA markers has provided more precise and efficient methods for tick species identification, but the currently available markers have limitations in their discriminatory power and sensitivity. To address this need for more sensitive and specific markers, this study aimed to identify two minimum sequence fragments required for tick Hyalomma and Rhipicephalus species identification using the Bm86 cDNA marker, which has previously been shown to be in perfect agreement with the current taxonomy of hard ticks based on its complete sequence. Based on our in silico determination that a minimum sequence of 398 bp for Rhipicephalus spp. (from 1487 to 1884) and 559 bp for Hyalomma species (from 539 to 1097) was necessary for species delineation, two distinct PCR assays were developed to apply these sequences in practice. Discrimination between species within each genus was achieved through sequence homology and phylogenetic analysis following the sequencing of the two PCR products. Subsequently, their performance was evaluated by testing them on the field-collected ticks of the Hyalomma and Rhipicephalus genera obtained from various host animals in different geographic regions of Tunisia. The use of shorter partial sequences specific to the tick genera Rhipicephalus and Hyalomma, which target the tick's RNA banks, could represent a significant advance in the field of tick species identification, providing a sensitive and discriminatory tool for interspecific and intraspecific diversity analysis.

Knowledge, Attitudes and Behaviors regarding Tick-Borne Encephalitis Vaccination and Prevention of Tick-Borne Diseases among Primary Care Physicians in Bavaria and Baden-Wuerttemberg, Germany, May-September 2022.

In 2020, a record number of tick-borne encephalitis (TBE) cases was reported in major endemic areas in Germany, i.e., the southern federal states of Baden-Wuerttemberg and Bavaria. Most cases were unvaccinated. Other tick-borne diseases (TBDs), including Lyme borreliosis and tularemia, are rising, too. Thus, strategies are needed to increase TBE vaccination uptake in risk areas and promote education on TBD prevention. Primary care physicians are key providers of both vaccinations and TBD education. The TBD-Prevention (TBD-Prev) study aimed to investigate the knowledge, attitudes and behaviors of primary care physicians in Baden-Wuerttemberg and Bavaria with regard to TBE vaccination and prevention of TBDs and to derive strategies for increasing vaccination rates and improving knowledge about TBE and other TBDs in the population and among primary care physicians. We invited all primary care physicians (N = 14,046) in both states to participate by mail. Using standardized, self-administered questionnaires, available both on paper and online, we asked physicians anonymously about their knowledge, attitudes and behaviors with respect to TBE vaccination and TBD prevention and their need for further information/educational materials. A total of 2321 physicians participated between May and September 2022 (response rate 17%), of whom 1222 (53%) worked in Baden-Wuerttemberg and 1067 (46%) in Bavaria. Among the participating physicians, 56% were male, 71% were >50 years and 51% worked in an individual practice. Furthermore, 91% were aware of the German national vaccination guidelines, and 98% perceived their knowledge of the risks and benefits of vaccination as adequate. A total of 97% offer TBE vaccinations, 67% provide vaccination counselling during initial consultations with new patients and 64% actively remind patients about due vaccinations. In addition, 24% expressed a need for further information materials, mainly traditional, analogue media such as flyers (82%) and posters (50%), and named timeliness, quality assurance, easy comprehensibility and independence from the pharmaceutical industry as the most important characteristics of such materials. Almost all participating physicians reported offering TBE vaccinations and feeling well-informed about TBE vaccination and TBDs. However, active offering of vaccinations and education could be further improved, and additional, low-threshold information materials are needed. Based on these results, we will develop and provide various materials on TBE vaccination and TBDs, in particular flyers and posters, for use by physicians during consultations.

Evaluation of a community-based One Health intervention to reduce the risk of Lyme disease in a high-incidence municipality

Abstract Integrated interventions coherent with the One Health approach are required to maximize the effectiveness of tick-borne disease prevention. The objective of this study was to evaluate the feasibility of a community-based One Health preventive intervention in a municipality reporting a high incidence of Lyme disease (LD) in the province of Quebec, Canada. The intervention integrated several activities to promote the adoption of preventive behaviours in the community (community component), with the reduction of infected ticks in the environment (environmental component). To evaluate short-term effects of the community component, quantitative data on knowledge, attitudes, and practices (KAP) of citizens were collected using online questionnaires at the beginning of the intervention and 1 year later. To evaluate the implementation of the intervention, a qualitative approach was principally used, and individual interviews (n=37) were conducted with key informants. Results showed that having a high level of participation in the community activities included in the intervention was associated with a higher adoption of preventive measures at the end of the intervention, although participation was not significantly associated with changes in KAP over the intervention period. Interviews revealed that the community mobilization approach was perceived as an effective and sustainable way to empower citizens and researchers with regard to LD prevention. This study suggests that community-based interventions of this type offer a promising approach to the prevention of tick-borne diseases.

Human palpebral infestation by mysterious laying eggs: A case report

AbstractPurpose: Tick infestation of ocular tissues is a rare occurrence. Ticks are ectoparasites which feed with animal blood. They are vectors of several diseases, as Lyme borreliosis, Crimean‐Congo hemorrhagic fever, typhus, Q fever,... We present the case of a tick infestation of the eyelid of a child.Methods: A 7‐year‐old girl presented for itchy eyelid, pain, and sensation of moving worms in the left superior eyelid. Her mother reported they just came back from vacation in Thailand, 3 days before. Examination of the left upper lid revealed one large moving ectoparasite with a group of eggs, laid below the upper eyelid. Some eggs had hatched, and small ticks were moving on and under the upper eyelid. Given the age of the girl and the nature of the infestation, it was impossible to remove the parasite and eggs at slit lamp. An appointment was settled the next day to remove them in operating room. The following day, the parasite detached itself from the eyelid. The sample was sent to a specialized center in tropical species. Careful examination revealed a slightly swollen palpebral conjunctiva towards the area where the tick was. Physical examination did not reveal other ectoparasite and treatment with Tobramycine was initiated as a precaution. The girl was sent to infectious diseases specialist to perform serologic tests.Results: The ectoparasite was identified as amblyomma sp tick. A shell insect infestation on the eyelid is not common at all. The cases found in literature describe cases of ticks feeding on the eyelid, but none of them reports the presence of eggs around the large ectoparasite (1). We supposed that the parasite stayed long enough to lay its eggs.Conclusions: Ophthalmologists are rarely confronted with ectoparasites and should be aware that removing the whole tick from the affected tissue is of important in the prevention of tickborne diseases and possible local complications (2). Serologic tests for tick‐borne diseases should be done and the patient monitored with clinical observation and follow‐up.

A One Health Evaluation of the Surveillance Systems on Tick-Borne Diseases in the Netherlands, Spain and Italy.

Simple SummaryIxodid ticks and tick-borne diseases are expanding their geographical range, but surveillance activities vary among countries. We analysed the surveillance systems in place in the Netherlands, Spain and Italy, to identify ideal elements to monitor tick-borne diseases, by using a One Health evaluation protocol. We identified differences among the three surveillance systems, with the Dutch initiative showing a high level of transdisciplinary collaboration, good identification of the actors and engagement of the public in research and education. Measurable outcomes have been generated, such as the reduction in tick bites and the discovery of new pathogens and tick species. In Italy and Spain, surveillance systems are based on compulsory notification to health authorities; legislation seems relevant but law enforcement alongside the availability of economic resources is rather fragmented and limited to the most severe diseases. The non-scientific community is marginally considered and collaborations are limited to local initiatives. Research activities in both countries have mostly contributed to gaining knowledge on the distribution of tick species and the discovery of new pathogens. Although all TBD surveillance plans comply with the EU regulations, the initiatives characterised by trans-disciplinary collaboration may be more effective for the surveillance and prevention of tick-transmitted diseases.To identify ideal elements for the monitoring and prevention of tick-borne diseases (TBD), we analysed the surveillance systems in place in the Netherlands, Spain and Italy. We applied a semi-quantitative evaluation to identify outcomes and assess the degree of One Health implementation. Differences emerged in the surveillance initiatives, as well as the One Health scores. The Dutch surveillance is dominated by a high level of transdisciplinary and trans-sectoral collaboration, enabling communication and data sharing among actors. Different project-based monitoring, research and educational activities are centrally coordinated and the non-scientific community is actively involved. All this yielded measurable health outcomes. In Italy and Spain, TBD surveillance and reporting systems are based on compulsory notification. Law enforcement, alongside dedicated time and availability of economic resources, is fragmented and limited to the most severe health issues. Veterinary and human medicine are the most involved disciplines, with the first prevailing in some contexts. Stakeholders are marginally considered and collaborations limited to local initiatives. Research activities have mostly contributed to gaining knowledge on the distribution of tick vectors and discovery of new pathogens. Although all TBD surveillance plans comply with EU regulations, initiatives characterised by transdisciplinary collaboration may be more effective for the surveillance and prevention of TBD.

Prevalence of Ehrlichia-, Babesia-, and Hepatozoon-infected brown dog ticks in Khon Kaen Province, Northeast Thailand.

Background and Aim:The brown dog tick, Rhipicephalus sanguineus sensu lato, is the most common tick found on domestic dogs in Southeast Asia, including Thailand. Canine tick-borne pathogens are a public health concern worldwide. Tick-borne diseases are diagnosed by identifying pathogens based on the morphological or molecular analyses of dog blood samples. However, the collection of ticks, a non-invasive procedure, is easier than drawing blood. This study aimed to demonstrate the usefulness of collecting brown dog ticks for the diagnosis of tick-borne diseases and for estimating the prevalence of tick-borne pathogens among companion dogs in Khon Kaen, Northeast Thailand.Materials and Methods:Seventy brown dog ticks from 70 companion dogs in Khon Kaen Province, Thailand, were evaluated for molecular evidence of tick-borne pathogens, including Babesia spp., Ehrlichia canis, and Hepatozoon canis. Ticks were collected from dogs at a private animal hospital based on the presence of at least one of the three inclusion criteria: fever, anorexia, or lethargy. Molecular diagnosis was performed using conventional polymerase chain reaction for the detection of pathogens.Results:Of the 70 ticks collected from 70 sick dogs, 55 (78.57%) were positive for tick-borne pathogens. The most common infection was a single infection with H. canis (65.71%) followed by Babesia spp. (31.43%) and E. canis (30.00%). Coinfection was observed in 14 ticks (20.00%), and coinfection with Babesia spp. and E. canis was the most prevalent double infection (n = 6). The prevalence of coinfection was identical for H. canis mixed with Babesia spp. and H. canis mixed with E. canis (n = 4).Conclusion:The present study showed that tick-borne pathogens are highly prevalent among companion dogs in Khon Kaen Province. Therefore, we encourage an increase in tick control or the reduction and prevention of tick-borne diseases in this region. Furthermore, this study revealed that ticks are valuable samples for the molecular detection of tick-borne pathogens.

One Health Approach to Tick and Tick-Borne Disease Surveillance in the United Kingdom.

Where ticks are found, tick-borne diseases can present a threat to human and animal health. The aetiology of many of these important diseases, including Lyme disease, bovine babesiosis, tick-borne fever and louping ill, have been known for decades whilst others have only recently been documented in the United Kingdom (UK). Further threats such as the importation of exotic ticks through human activity or bird migration, combined with changes to either the habitat or climate could increase the risk of tick-borne disease persistence and transmission. Prevention of tick-borne diseases for the human population and animals (both livestock and companion) is dependent on a thorough understanding of where and when pathogen transmission occurs. This information can only be gained through surveillance that seeks to identify where tick populations are distributed, which pathogens are present within those populations, and the periods of the year when ticks are active. To achieve this, a variety of approaches can be applied to enhance knowledge utilising a diverse range of stakeholders (public health professionals and veterinarians through to citizen scientists). Without this information, the application of mitigation strategies to reduce pathogen transmission and impact is compromised and the ability to monitor the effects of climate change or landscape modification on the risk of tick-borne disease is more challenging. However, as with many public and animal health interventions, there needs to be a cost-benefit assessment on the most appropriate intervention applied. This review will assess the challenges of tick-borne diseases in the UK and argue for a cross-disciplinary approach to their surveillance and control.

Prevention of tick-borne diseases: challenge to recent medicine.

Ticks represent important vectors and reservoirs of pathogens, causing a number of diseases in humans and animals, and significant damage to livestock every year. Modern research into protection against ticks and tick-borne diseases focuses mainly on the feeding stage, i.e. the period when ticks take their blood meal from their hosts during which pathogens are transmitted. Physiological functions in ticks, such as food intake, saliva production, reproduction, development, and others are under control of neuropeptides and peptide hormones which may be involved in pathogen transmission that cause Lyme borreliosis or tick-borne encephalitis. According to current knowledge, ticks are not reservoirs or vectors for the spread of COVID-19 disease. The search for new vaccination methods to protect against ticks and their transmissible pathogens is a challenge for current science in view of global changes, including the increasing migration of the human population.Highlights• Tick-borne diseases have an increasing incidence due to climate change and increased human migration• To date, there is no evidence of transmission of coronavirus COVID-19 by tick as a vector• To date, there are only a few modern, effective, and actively- used vaccines against ticks or tick-borne diseases• Neuropeptides and their receptors expressed in ticks may be potentially used for vaccine design

Exploring the effects of pathogen infection on tick behaviour from individuals to populations

Ticks vector a greater variety of pathogens than any other arthropod group, making them a significant threat to the public, companion animals and wildlife. Surveying wildlife habitats and areas commonly used for recreation for the presence of ticks and the pathogens that they carry is essential to the prevention of tick-borne diseases. Tick behaviour also plays an active role in transmission dynamics. We set out to study the host-seeking behaviour of Amblyomma americanum , the lone star tick, at the population level and at the individual level by collecting ticks in public parks in Gainesville, Florida, U.S.A., and by conducting behavioural assays on host-seeking behaviour (questing). We assayed a subset of the collected ticks for 3 consecutive days to determine whether ticks displayed repeatable, individual level differences in questing behaviour. Afterward, we screened ticks for two human pathogens, Rickettsia spp. and Ehrlichia spp. While we did not find differences in pathogen prevalence among the populations, we found that nymphal ticks infected with Rickettsia amblyommatis spent less time questing than uninfected nymphs. However, across all populations, we found a greater prevalence of R. amblyommatis in adult ticks. Additionally, nymphs were more likely to engage in questing behaviours than adults. Lastly, we found significant repeatability in the average height that a tick quests and the questing likelihood of a tick. These findings could fill a gap in the knowledge about trends in disease dynamics. • Ticks displayed repeatability in average heights quested and the likelihood to quest. • Infected nymphal ticks spent less time questing than uninfected nymphs. • Nymphs were more likely to engage in questing behaviours than adult ticks. • Ticks from rural sites quested higher on average compared to ticks from city parks.

Knowledge, attitudes, and behaviors regarding tick-borne disease prevention in Lyme disease-endemic areas of the Upper Midwest, United States

Lyme disease and other tick-borne diseases are a major public health threat in the Upper Midwestern United States, including Michigan, Minnesota, and Wisconsin. To prevent tick bites and tick-borne diseases, public health officials commonly recommend personal protective measures and property management techniques. Adoption of tick-borne disease prevention behaviors and practices by individuals are, however, highly variable. We aimed to characterize current tick-borne disease knowledge, attitudes, and prevention behaviors (KAB) practiced by the public in these states, as well as their willingness to use specific tick control methods. We conducted a population-based survey in summer 2019 in 48 high-risk counties (those having a five-year average (2013–2017) Lyme disease incidence of ≥ 10 cases per 100,000 persons per year), in Michigan, Minnesota, and Wisconsin. A total of 2713 surveys were analyzed; survey weights were used to account for household selection probability and post-stratified to match county-level joint age and sex population distributions in population-level inference. An estimated 98% of the population had heard of Lyme disease, with most perceiving it as very or extremely serious (91%); however, only an estimated 25% perceived tick-borne diseases as very or extremely common in their community. Among those who spent time in places with ticks from April through October, an estimated 68% check themselves thoroughly for ticks most of the time or always and 43% use bug repellent on skin or clothing most of the time or always. An estimated 13% of the population had ever treated their property with a pesticide to kill ticks, and 3% had ever used devices that apply pesticide to rodents to kill ticks on their property. Willingness to practice tick bite prevention behaviors, however, was estimated to be much higher; with 82% being willing to perform tick checks at least once a day, and more than 60% willing to use bug repellent, tick control products on pets, or to bathe within two hours of being outdoors. We found that residents would likely be willing to support a county-wide tick control program to reduce the risk of tick-borne disease in their community (81%) or to apply tick control products to their property to reduce the risk of tick-borne disease in their household (79%). Tick checks were more likely to be practiced among participants who perceived tick-borne diseases to be highly prevalent in their community, if they or a household member had been previously diagnosed with a tick-borne disease?, or if they perceived tick exposure to be likely around their home, cabin, or vacation home. In addition, property-based tick control methods were associated with perceived risk of encountering ticks around the home, cabin, or vacation home. Participants who had seen information from state health departments were also more likely to practice preventive measures. The most common reported barriers to using any of these methods were forgetfulness, safety concerns, and lack of awareness. Our survey findings shed light on how residents from these Upper Midwest states may adopt tick control and tick bite prevention measures and how public health outreach may be most effective for this population.

1198. Lyme Disease Post-Exposure Prophylaxis by Single-Dose Doxycycline in Three Healthcare Systems

BackgroundLyme disease, the most common tickborne disease in the United States, may be prevented by taking a single 200-mg dose of oral doxycycline after a high-risk bite from a blacklegged tick. Currently, it is not known how Lyme disease post-exposure prophylaxis (PEP) might vary by region and healthcare system. We identified single-dose doxycycline medication orders in three healthcare systems in states with high incidence of Lyme disease and compared associated patient and provider characteristics. MethodsElectronic health record data during 2012 – 2016 were obtained from three healthcare systems: Geisinger (Pennsylvania), Marshfield Clinic (Wisconsin), and Mayo Clinic (Minnesota/Wisconsin). Creation of analytic variables and analysis were harmonized across the three sites. Medication orders for single-dose doxycycline ≤200 mg that were accompanied by specific key words or diagnostic codes (e.g., tick bite; Lyme disease prevention) were considered evidence of PEP. Manual chart review was performed from a random subset to evaluate the algorithms used to identify PEP. ResultsAmong 2,937,585 patients with at least one medication order or clinical encounter during the study period, 14,102 single-dose doxycycline orders for Lyme disease PEP for 13,172 unique patients were identified. The typical patient receiving PEP was older (mean age 51 – 58 years), male (56 – 59%), and non-Hispanic White (81 – 98%). The annual seasonality of medication orders was bimodal, with peaks occurring during April – July and October – November. The most common encounter setting was an outpatient clinic or urgent care center (80 – 91%); medication orders after patient phone calls in the absence of an in-person visit occurred frequently (14 – 19%) in two health systems. Chart abstractions (n=600) revealed instances of PEP prescribed inappropriately (e.g., bite from a non-blacklegged tick; patient with symptoms of acute Lyme disease).ConclusionLyme disease PEP with a single dose of doxycycline was frequently prescribed in healthcare systems where there is a high incidence of Lyme disease. PEP was most commonly prescribed to non-Hispanic Whites over the age of 50 years. Public health initiatives for tickborne disease prevention should include clinician education on the appropriate use of Lyme disease PEP.Disclosures Anna M. Schotthoefer, PhD, HelixBind (Other Financial or Material Support, salary support) John Zeuli, PharmD, INSMED (Other Financial or Material Support, honoraria for educational speaking)

Tick-Borne Disease Prevention Behaviors Among Participants in a Tick Surveillance System Compared with a Sample Of Master Gardeners

Theory-based approaches to health communication and behavior are increasingly applied to interventions that address poor public tick-borne disease prevention knowledge and practices. We sought to understand the tick-borne disease prevention behaviors among participants in a crowdsourced passive tick surveillance system that employs theory-based messages about tick bite risk and prevention strategies. We administered an electronic survey to a randomly selected sample of passive surveillance system users and compared their responses to those from a nationwide sample of Master Gardeners (MG), a group with heighten tick exposure due to outdoor activity. Over 80% of TickSpotters respondents, and over 75% of MG respondents encountered a tick in the past year. Among both groups, tick checks were the most frequently practiced prevention behavior, with over 70% of people performing them most or all the time after outdoor activity. A greater proportion of MGs used skin repellents such as DEET or picaridin than TickSpotters users, but more than 70% of respondents from both groups reported that they never or only sometimes use permethrin-treatment on clothing, and nearly half of both groups reportedly used no peridomestic tick treatments. TickSpotters respondents overwhelmingly reported recording tick encounter information and saving specimens for identification and testing, while only a small percentage of MGs monitored their tick encounters. These findings suggest that while both TickSpotters and MG groups appear to be practicing some important tick bite prevention behaviors, there remain areas that could benefit from targeted theory-based interventional approaches.

Active surveillance of ticks in peri-domestic areas of Indiana, Midwest United States.

The incidence of Borreliosis, Anaplasmosis, Babesiosis and other tick-borne diseases acquired from private residential/peri-domestic areas has increased over the decades. However, tick activity and proportion of private residential properties with established tick populations remain unknown. The purpose of the current study was to determine the predictors of tick activity in peri-domestic areas. In a cross-sectional study design, we used snowball-sampling with cold-calling techniques to collect free-living ticks, sociodemographic, and microclimatic data from June to November 2018 from a total of 96 private residential areas in south-central Indiana, USA. Thirty-eight percent of peri-domestic areas sampled had tick activity, and of these, 50% had established tick populations. Nymphal ticks were the most abundant life stage. Self-reported TBD diagnosis was 16%. Amblyomma americanum [Linnaeus (lone star tick)] was the most abundant tick species collected. Other tick species identified include: Ixodes scapularis [Say (black-legged/deer tick)] and Dermacentor variabilis [Say (American dog tick)]. Increasing temperature was positively associated with tick activity, while elevation was negatively associated with tick abundance. Our study results reveal that the proportion of peri-domestic areas in Indiana with established tick populations is high. Amblyomma americanum tick is the most predominant tick species in peri-domestic areas of south-central Indiana. Active surveillance of ticks in peri-domestic areas is necessary for informing decisions by households and communities about where to target tick exposure and tick-borne disease prevention efforts.

Tick treatment practices in the field: Access to, knowledge about, and on-farm use of acaricides in Laikipia, Kenya

The prevention of tick-borne diseases is a major challenge for livestock production globally. Tick control strategies include the use of acaricides, but the prescribed strategies do not achieve the desired results in several countries, including Kenya. To better understand how tick treatment practices, contribute to reported tick treatment failures, we assessed livestock owners’ acaricide procurement, level of knowledge about acaricides and tick resistance, and how they apply acaricides. We also assessed the quality of the commonly available acaricides. We focused on three livestock systems in Laikipia County, Kenya: two private ranches; one community ranch whose members communally graze their cattle and acquire and apply acaricides; and individual livestock owners in two pastoral communities who individually graze their cattle and acquire and apply acaricides. Through interviews and focus group discussions we assessed; access to acaricides, livestock owners’ knowledge, and acaricide use practices; interview data were triangulated with participant observations (n = 107). We analysed nine commonly used acaricides to determine the active ingredient concentration and we determined the concentration of active ingredients in acaricide dilutions collected on farms. All livestock owners had access to and used chemical acaricides for tick control, predominantly amitraz-based. Private ranchers bought one amitraz-based acaricide in bulk directly from the manufacturer, while all other livestock owners bought from agrovet shops. The livestock owners acquired knowledge about acaricides from their own experiences and through experience-based recommendations from peers, but not from the technical information provided by the manufacturers and agrovet shops. All pastoral livestock frequently changed acaricide brand and active ingredient class. A large majority of pastoralists (86%) mixed acaricide brands within and across active ingredient classes; a smaller majority (56%) mixed acaricides with crop pesticides and insecticides. Our lab tests confirmed the content description on the labels bought from agrovet shops. However, on-farm acaricide dilutions from all three livestock systems deviated from the level recommended for effective treatment. If too diluted, the acaricide does not kill ticks, promoting resistance development. If too concentrated, this increases environmental contamination and raises public health concerns. Livestock owners lack a technical understanding of the functioning of acaricides, compromising their use and effectiveness. The widely adopted mixing of acaricides with insecticides and pesticides raises serious health concerns.