Pet ownership increases human risk of encountering ticks

Urban tick exposure on Staten Island is higher in pet owners

Over the past decade, Lyme and other tick-borne diseases have expanded into urban areas, including Staten Island, New York. While Lyme disease is often researched with a focus on human risk, domestic pets are also at risk of contracting the disease. The present study aims to describe differences in tick exposure, knowledge, attitude, and practices (KAP) between pet owners and non-owners, and to understand preventive strategies practiced by pet owners for themselves and their pets. We conducted KAP surveys via phone in 2020 and via face-to-face interviews in 2021, and we analyzed unique responses from 364 households on Staten Island. Pet owners were more likely to have ever found a tick on themselves or their household members (63%) than non-owners (46%) (p<0.001). Among pet owners, those who owned dogs (dog-only or both dog and cat owners) were more likely to have ever found a tick on their pets than cat-only owners (p<0.001). Compared with non-pet owners, pet owners were more likely both to know that ticks transmit Lyme disease (p<0.001) and to avoid gardening to reduce their tick exposure (p = 0.032), but they were less likely to wear protective clothing or adjust clothing (p = 0.013). Compared with cat owners who had never found a tick on their cats, cat owners who had ever found a tick on their cats were more likely to let their cats go outside (p<0.001). However, reported preventive measures on cats did not differ between pet owners who did and did not report tick exposure. The results indicate that encouraging pet owners to engage in preventative measures, both to protect themselves and their pets, is a potential avenue for healthcare providers and veterinarians to reduce risks from ticks.

Outdoor worker knowledge of ticks and Lyme disease in Québec

BACKGROUND AND AIMS

Lyme disease is a well-known occupational risk across North America caused by exposure to Borrelia burgdorferi via blacklegged ticks (Ixodes scapularis). As the geographic range of B. burgdorferi advances with the increasing distribution of blacklegged ticks, more outdoor workers are at risk of contracting Lyme disease. In this study, we examined the demography and personal perceptions of outdoor workers within one framework to better determine the overall risk for those working outdoors.

METHODS AND RESULTS

We analysed outdoor worker knowledge of ticks and of behaviours that can prevent tick bites and Lyme disease. We then compared these risk perceptions of individuals across age, sex, education, and industry, as well as time spent outdoors. We tested the hypothesis that the risk perception of an individual and their knowledge of Lyme disease transmission was dependent on their demographics, experience in their job, and the region in which they spend time outdoors. We estimated a knowledge-based risk score based on individuals' answers to a questionnaire on risk perception given to voluntary participants who work outdoors. Those who had higher risk scores were more at risk. We found that knowledge-based risk scores were correlated with geographic risk levels and with the number of hours per day spent outdoors. Those who work longer hours and who work in areas with mid-level risk had higher risk scores. Those who spend more time outdoors recreationally had lower risk scores.

CONCLUSIONS

Further examination and acknowledgment of the reasoning behind why these factors are affecting workers' risks must be considered to recognize that it is not necessarily demographics or geographically high-risk areas that affect an individual's risk. Workers' knowledge of these risks is affected by several variables that should be taken into consideration when implementing safety measures and awareness programs.

Age- and Sex-Specific Differences in Lyme Disease Health-Related Behaviors, Ontario, Canada, 2015-2022

We investigated differences in risk factors and preventive behaviors by age and sex among persons with reported Lyme disease in Ontario, Canada, during 2015-2022. Incidence rates peaked among children 5-9 and adults 50-79 years of age. Median age was higher for female than male case-patients (54 vs. 51 years). Male case-patients reported more activity in wooded and tall grass areas than did female case-patients; fewer male case-patients reported sharing living space with outdoor-exposed companion animals. As age increased, more case-patients reported activity in blacklegged tick habitats, exposure to ticks, and wearing adequate clothing, but fewer reported sharing living space with outdoor-exposed companion animals. Adoption of preventive behaviors was relatively low and did not differ by sex. Male case-patients, children 5-9 years of age and their parents or caregivers, and adults >59 years of age represent populations that would benefit from tailored public health messaging on Lyme disease prevention.

Nationwide survey of ticks on domesticated animals in Taiwan: Revealing the hidden threat to animal and public health

Ticks are not only bloodsucking ectoparasites but also important vectors of tick-borne diseases (TBDs), posing significant threats to public and animal health. Domesticated animals serve as critical hosts for numerous ticks, highlighting the importance of understanding tick infestations in Taiwan. To address this knowledge gap, we conducted a nationwide survey to identify ticks on domesticated animals and associated environments in 2018 and 2019. A total of 6,205 ticks were collected from 1,337 host animals, revealing the presence of seven tick species, with Rhipicephalus microplus, and Rhipicephalus sanguineus being the dominant species. High infestation rates and widespread distribution of ticks were observed on domesticated animals, especially on dogs and cattle (yellow cattle and angus cattle), and the neighbouring grassland of yellow cattle. While this study has certain limitations, it provides valuable insights into the distribution and prevalence of ticks on domesticated animals in Taiwan and their implications for controlling TBDs. Further research is needed to comprehensively understand the complex interactions among ticks, hosts and pathogens.

Tick Diversity and Pathogen Transmission in Daejeon, Korea: Implications from Companion Animals and Walking Trails

With the ongoing global warming-induced climate change, there has been a surge in vector-borne diseases, particularly tick-borne diseases (TBDs). As the population of companion animals grows, there is growing concern from a One Health perspective about the potential for these animals to spread TBDs. In this study, ticks were collected from companion animals and the surrounding environment in Daejeon Metropolitan City, Korea, using flagging and dragging, and CO2 trap methods. These ticks were then subjected to conventional (nested) PCR for severe fever with thrombocytopenia syndrome virus (SFTSV), Anaplasma spp., Ehrlichia spp., and Borrelia spp. We identified a total of 29,176 ticks, consisting of three genera and four species: H. longicornis, H. flava, I. nipponensis, and A. testudinarium. Notably, H. longicornis was the predominant species. The presence of A. testudinarium suggested that the species traditionally found in southern regions are migrating northward, likely as a result of climate change. Our PCR results confirmed the presence of all four pathogens in both companion animals and the surrounding environment, underscoring the potential for the indirect transmission of tick-borne pathogens to humans through companion animals. These findings emphasize the importance of the ongoing surveillance of companion animals in the management and control of TBDs.

Risk factors for tick attachment in companion animals in Great Britain: a spatiotemporal analysis covering 2014-2021

BACKGROUND

Ticks are an important driver of veterinary health care, causing irritation and sometimes infection to their hosts. We explored epidemiological and geo-referenced data from > 7 million electronic health records (EHRs) from cats and dogs collected by the Small Animal Veterinary Surveillance Network (SAVSNET) in Great Britain (GB) between 2014 and 2021 to assess the factors affecting tick attachment in an individual and at a spatiotemporal level.

METHODS

EHRs in which ticks were mentioned were identified by text mining; domain experts confirmed those with ticks on the animal. Tick presence/absence records were overlaid with a spatiotemporal series of climate, environment, anthropogenic and host distribution factors to produce a spatiotemporal regression matrix. An ensemble machine learning spatiotemporal model was used to fine-tune hyperparameters for Random Forest, Gradient-boosted Trees and Generalized Linear Model regression algorithms, which were then used to produce a final ensemble meta-learner to predict the probability of tick attachment across GB at a monthly interval and averaged long-term through 2014-2021 at a spatial resolution of 1 km. Individual host factors associated with tick attachment were also assessed by conditional logistic regression on a matched case-control dataset.

RESULTS

In total, 11,741 consultations were identified in which a tick was recorded. The frequency of tick records was low (0.16% EHRs), suggesting an underestimation of risk. That said, increased odds for tick attachment in cats and dogs were associated with younger adult ages, longer coat length, crossbreeds and unclassified breeds. In cats, males and entire animals had significantly increased odds of recorded tick attachment. The key variables controlling the spatiotemporal risk for tick attachment were climatic (precipitation and temperature) and vegetation type (Enhanced Vegetation Index). Suitable areas for tick attachment were predicted across GB, especially in forests and grassland areas, mainly during summer, particularly in June.

CONCLUSIONS

Our results can inform targeted health messages to owners and veterinary practitioners, identifying those animals, seasons and areas of higher risk for tick attachment and allowing for more tailored prophylaxis to reduce tick burden, inappropriate parasiticide treatment and potentially TBDs in companion animals and humans. Sentinel networks like SAVSNET represent a novel complementary data source to improve our understanding of tick attachment risk for companion animals and as a proxy of risk to humans.

Distribution of Rhipicephalus sanguineus and Heamaphysalis elliptica dog ticks and pathogens they are carrying: A systematic review

The role of ixodid ticks especially Rhipicephalus sanguineus and Heamaphysalis elliptica in the epidemiology of several diseases of veterinary and public health importance have been documented. This study conducted a systematic review focusing on the distribution of R. sanguineus and H. elliptica, as well as the common tick-borne pathogens they harbour. The Scopus, ScienceDirect, PubMed, and Web of Science databases were used to search for English journal articles published between January 1990 and June 2021. The articles were assessed by following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. This systematic review was registered on PROSPERO [(ID no: CRD42022327372). Of the studies included in the systematic review, 247 and 19 articles had identified R. sanguineus and H. elliptica respectively, whereas 15 articles had identified both tick species. There is a reported worldwide distribution of R. sanguineus from 64 countries, whereas H. elliptica was only reported in the African continent from 6 countries. In total, 120 articles that were included in this systematic review reported detection of tick-borne pathogens from R. sanguineus (n = 118 articles) and/or H. elliptica (n = 2 articles) ticks. According to the studies tick-borne pathogens harboured by R. sanguineus included protozoa such as Babesia spp., Hepatozoon spp., Leishmania spp., and Theileria spp., as well as bacteria such as Acinetobacter spp. Anaplasma spp., Bacillus spp., Borrelia spp., Brucella spp., Coxiella spp., and Staphylococcus spp. The H. elliptica was reported to be harbouring Babesia spp., Ehrlichia spp. and Rickettsia spp. Most of the studies (50%) used the conventional polymerase chain reaction (PCR) technique for the detection of tick-borne pathogens, followed by real-time PCR (qPCR) (n = 26), and nested PCR (n = 22). This systematic review has shed light on the distribution of two common dog ticks as well as the tick-borne pathogens of veterinary and zoonotic importance they are harbouring. This data will enable surveillance studies that can report whether the distribution of these ticks and their associated tick-borne pathogens is expanding or shrinking or is stable.

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.

Essential oils and isolated compounds for tick control: advances beyond the laboratory

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.

Ticks and tick-borne rickettsiae from dogs in El Salvador, with report of the human pathogen Rickettsia parkeri

Twelve tick species have been reported in El Salvador; however, information regarding ticks infesting domestic dogs is lacking, and pathogenic tick-borne Rickettsia species have never been reported in El Salvador. This work evaluated ticks infesting 230 dogs from ten municipalities in El Salvador from July 2019 to August 2020. A total of 1,264 ticks were collected and identified into five species: Rhipicephalus sanguineus sensu lato (s.l.), Rhipicephalus microplus, Amblyomma mixtum, Amblyomma ovale, and Amblyoma cf. parvum. The tick R. sanguineus s.l. was the most frequent species in all localities (81.3% of sampled dogs), followed by Amblyomma mixtum (13.0%), Amblyomma ovale (10.9%) and Amblyomma cf. parvum (10.4%). The overall mean intensity of tick infestation was 5.5 ticks/dog. The highest specific mean intensity value was for R. sanguineus s.l. (4.8 ticks/dog), varying from 1.6 to 2.7 ticks/dog for the three Amblyomma species. From a random sample of 288 tick specimens tested molecularly for the presence of rickettsial agents, three spotted fever group Rickettsia were detected: Rickettsia amblyommatis in 90% (36/40) A. mixtum, 46% (11/24) A. cf. parvum, 4% (7/186) R. sanguineus s.l., and 17% Amblyomma spp.; Rickettsia parkeri strain Atlantic rainforest in 4% (1/25) A. ovale; and an unnamed rickettsia agent, designated as 'Rickettsia sp. ES-A.cf.parvum', in 4% (1/24) A. cf. parvum. Our finding of R. parkeri strain Atlantic rainforest in A. ovale is highly relevant because this agent has been associated to spotted fever illness in other Latin American countries, where A. ovale is implicated as its main vector. These findings suggest that spotted fever cases caused by R. parkeri strain Atlantic rainforest could be occurring in El Salvador.

Improving Surveillance of Human Tick-Borne Disease Risks: Spatial Analysis Using Multimodal Databases

BACKGROUND

The extent of tick-borne disease (TBD) risk in the United States is generally unknown. Active surveillance using entomological measures, such as presence and density of infected nymphal Ixodes scapularis ticks, have served as indicators for assessing human risk, but results have been inconsistent and passive surveillance via public health systems suggests TBDs are underreported.

OBJECTIVE

Research using various data sources and collection methods (eg, Google Trends, apps, and tick bite encounters [TBEs] reports) has shown promise for assessing human TBD risk. In that vein, and engaging a One Health perspective, this study used multimodal databases, geographically overlaying patient survey data on TBEs and concomitant reports of TBDs with data drawn from other sources, such as canine serological reports, to glean insights and to determine and assess the use of various indicators as proxies for human TBD risk.

METHODS

This study used a mixed methods research strategy, relying on triangulation techniques and drawing on multiple data sources to provide insights into various aspects of human disease risk from TBEs and TBDs in the United States. A web-based survey was conducted over a 15-month period beginning in December 2020 to collect data on TBEs. To maximize the value of the covariate data, related analyses included TBE reports that occurred in the United States between January 1, 2000, and March 31, 2021. TBEs among patients diagnosed with Lyme disease were analyzed at the county level and compared to I scapularis and I pacificus tick presence, human cases identified by the Centers for Disease Control and Prevention (CDC), and canine serological data. Spatial analyses employed multilayer thematic mapping and other techniques.

RESULTS

After cleaning, survey results showed a total of 249 (75.7%) TBEs spread across 148 respondents (61.9% of all respondents, 81.7% of TBE-positive respondents); 144 (4.7%) counties in 30 states (60%) remained eligible for analysis, with an average of 1.68 (SD 1.00) and median of 1 (IQR 1) TBEs per respondent. Analysis revealed significant spatial matching at the county level among patient survey reports of TBEs and disease risk indicators from the CDC and other official sources. Thematic mapping results included one-for-one county-level matching of reported TBEs with at least 1 designated source of human disease risk (ie, positive canine serological tests, CDC-reported Lyme disease, or known tick presence).

CONCLUSIONS

Use of triangulation methods to integrate patient data on TBE recall with established canine serological reports, tick presence, and official human TBD information offers more granular, county-level information regarding TBD risk to inform clinicians and public health officials. Such data may supplement public health sources to offer improved surveillance and provide bases for developing robust proxies for TBD risk among humans.

Zoonotic Dermatoses of Exotic Companion Mammals

Integumentary disorders caused by zoonotic agents are very common in exotic companion mammals. This article provides an understanding of the main zoonotic dermatoses including parasitic, fungal, bacterial, and viral diseases to provide the most updated information on their epidemiology, diagnosis, reported clinical signs, and therapies.

Knowledge, attitudes, and practices of Illinois medical professionals related to ticks and tick-borne disease

Background

The rising incidence of tick-borne disease (TBD) underscores the importance of proficiency in TBD diagnosis. Clinicians' knowledge about vector ticks and TBDs in their area may influence whether patients are questioned about potential tick exposure and the consideration of diagnostic testing for TBDs.

Objective

Our objective was to assess the knowledge, attitudes, and practices of Illinois clinicians towards ticks and TBDs. The study aimed to 1) identify predictors associated with knowledge, 2) identify knowledge gaps, and 3) evaluate attitudes and practices related to TBDs.

Methods

A web-based knowledge, attitudes, and practices survey about Illinois ticks and TBDs was disseminated to physicians, mid-level practitioners, and nurses between August 2020 and February 2022. Poisson regression analysis was conducted to identify predictors of higher scores.

Results

Of 346 respondents, 80% correctly identified Lyme disease as endemic to Illinois, and 95% were familiar with diagnostic testing for Lyme. Knowledge of other TBDs present in the state was highest among physicians, yet only 26% of physicians believed Rocky Mountain spotted fever (RMSF) to be present in Illinois, and only 17% believed ehrlichiosis to be endemic. Only 32% of physicians knew the cause of Alpha-gal syndrome and fewer than 18% were aware of available diagnostic testing. Tick or TBD-related education within the past two years was the most significant predictor of higher scores, increasing overall knowledge scores by 26% (RR 1.26, 95% CI 1.13-1.41) and increasing scores specific to TBDs by 42% (RR 1.42, 95% CI 1.19-1.69).

Conclusion

Illinois clinicians were informed about Lyme disease but lacked knowledge of other TBDs endemic to the state, including RMSF, ehrlichiosis, and Alpha-gal syndrome. The strongest predictor of knowledge was tick/TBD training in the previous two years, highlighting the importance of frequent region-specific training on ticks and TBDs.

Risk of tick-borne pathogen spillover into urban yards in New York City

BACKGROUND

The incidence of tick-borne disease has increased dramatically in recent decades, with urban areas increasingly recognized as high-risk environments for exposure to infected ticks. Green spaces may play a key role in facilitating the invasion of ticks, hosts and pathogens into residential areas, particularly where they connect residential yards with larger natural areas (e.g. parks). However, the factors mediating tick distribution across heterogeneous urban landscapes remain poorly characterized.

METHODS

Using generalized linear models in a multimodel inference framework, we determined the residential yard- and local landscape-level features associated with the presence of three tick species of current and growing public health importance in residential yards across Staten Island, a borough of New York City, in the state of New York, USA.

RESULTS

The amount and configuration of canopy cover immediately surrounding residential yards was found to strongly predict the presence of Ixodes scapularis and Amblyomma americanum, but not that of Haemaphysalis longicornis. Within yards, we found a protective effect of fencing against I. scapularis and A. americanum, but not against H. longicornis. For all species, the presence of log and brush piles strongly increased the odds of finding ticks in yards.

CONCLUSIONS

The results highlight a considerable risk of tick exposure in residential yards in Staten Island and identify both yard- and landscape-level features associated with their distribution. In particular, the significance of log and brush piles for all three species supports recommendations for yard management as a means of reducing contact with ticks.

Personal protection measures to prevent tick bites in the United States: Knowledge gaps, challenges, and opportunities

Personal protection measures to prevent human tick encounters from resulting in bites are widely recommended as the first line of defense against health impacts associated with ticks. This includes using repellents, wearing untreated or permethrin-treated protective clothing, and conducting tick checks after coming inside, aided by removing outdoor clothing articles and running them in a dryer on high heat (to kill undetected ticks) and taking a shower/bath (to aid in detecting ticks on the skin). These measures have the benefit of incurring no or low cost, but they need to be used consistently to be most effective. In this paper, I review the level of use (acceptability combined with behavior) of the above-mentioned personal protection measures and their effectiveness to prevent tick bites and tick-borne disease. Studies on the level of use of personal protection measures to prevent tick bites have used different recruitment strategies, focused on different types of respondent populations, employed variable phrasings of survey questions relating to a given personal protection measure, and presented results based on variable frequencies of taking action. This complicates the synthesis of the findings, but the studies collectively indicate that members of the public commonly take action to prevent tick bites, most frequently by wearing untreated protective clothing or conducting tick checks (done routinely by 30 to 70% of respondents in most studies of the public), followed by showering/bathing after being outdoors or using repellents on skin/clothing (15 to 40% range), and with permethrin-treated clothing being the least frequently used tick bite prevention method (<5 to 20% range). A suite of experimental studies have shown that applying repellents or permethrin to coveralls or uniform-style clothing can result in decreased numbers of tick bites, but similar studies are lacking for members of the public wearing summer-weight clothing during normal daily activities. Moreover, a set of case-control and cross-sectional studies have explored associations between use of different personal protection measures to prevent tick bites and Lyme disease or other tick-borne infections. The results are mixed for each personal protection measure, with some studies indicating that regular use of the measure is associated with a reduction in tick-borne disease while other studies found no similar protective effect. One possible interpretation is that these personal protection measures can protect against tick-borne infection but the information gathered to date has not been sufficiently detailed to clarify the circumstances under which protection is achieved, especially with regards to frequency of use, parts of the body being protected, and use of combinations of two or more potentially protective measures. In conclusion, personal protection measures to prevent tick bites are used by the public and merit further study to better understand how they need to be used to have the greatest public health impact.

Knowledge, attitudes, and practices of veterinary professionals towards ticks and tick-borne diseases in Illinois

Objective

A lack of standardized surveillance or reporting of tick-borne diseases (TBDs) in Illinois creates uncertainty for veterinarians regarding TBDs occurring within their practice geography or which TBDs may be encroaching on their area from neighboring territories. Therefore, the objective of this study was to gauge the knowledge, attitudes, and practices of veterinary professionals in Southern and Central Illinois to establish a foundation for targeting educational and outreach programs that address knowledge gaps.

Sample

72 veterinary professionals in Central and Southern Illinois.

Procedures

An online knowledge, attitudes, and practices survey was distributed to veterinary professionals in Southern and Central Illinois. Poisson regression analyses were conducted to determine factors associated with knowledge scores and the estimated number of TBD cases diagnosed.

Results

Knowledge scores were significantly higher among veterinary practitioners with recent (within the last 5 years) training on TBD. The number of cases of TBD diagnosed was higher among those reporting concern about TBD, and among those who routinely test for TBDs. The types of diseases diagnosed were heavily influenced by the diagnostic method used.

Clinical relevance

This study paints a cohesive picture of human factors associated with diagnosing veterinary diseases and TBD prevalence in Southern and Central Illinois. Our results highlight the importance and practical value of veterinary continuing education on ticks and TBDs for both companion animals and public health. Building capacity for training veterinarians in parasitology using partnerships between academia and industry may strengthen the knowledge and understanding of ticks and tick-borne pathogens in the veterinary community.

Human Otoacariasis in Two Climatically Diverse Districts in Sri Lanka: Seasonality, Risk Factors, and Case Notes

PURPOSE

Otoacariasis is a parasitic otopathy reported in many parts of the world. This study presents the seasonal pattern, risk factors, and case notes on human otoacariasis in two climatically different districts: Anuradhapura and Kandy in the Dry and Wet/Intermediate zone of Sri Lanka, respectively.

METHODS

Ticks removed from the ear canal of patients were collected. Risk factors of otoacarisis were determined by a case/control follow-up study.

RESULTS

Nymphal Dermacentor auratus (90.8%) was the main tick species associated otoacariasis. In the Kandy District, infestation was year-round, while in the Anuradhapura District, it was seasonal with a peak in December-February. Children < 10 years were a risk group in both districts. Females were a risk group in the Kandy District. Engagement in outdoor activities was a risk factor in both districts. In addition, the presence of wildlife and domesticated animals were risk factors in the Kandy and Anuradhapura districts, respectively. The treatment protocols in the two hospitals were different. An infant with otoacariasis from the Anuradhapura District developed rickettsia.

CONCLUSIONS

Although the tick species was the same, seasonality, risk groups, and risk factors in the two districts were different which could be due to the establishment and persistence of tick populations influenced by biotic and abiotic factors.

The Role of Ticks in the Emergence of Borrelia burgdorferi as a Zoonotic Pathogen and Its Vector Control: A Global Systemic Review

Ticks are widely distributed across the globe, serving as hosts for numerous pathogens that make them major contributors to zoonotic parasitosis. Borrelia burgdorferi is a bacterial species that causes an emerging zoonotic tick-borne disease known as Lyme borreliosis. The role of ticks in the transmission of this pathogen was explored in this study. According to this systematic review, undertaken according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, 19 tick species are known to carry Borrelia burgdorferi, with more than half of the recorded cases in the last two decades related to Ixodes ricinus and Ixodes scapularis ticks. Forty-six studies from four continents, Europe, North America, Asia, and Africa, reported this pathogen in ticks collected from vegetation, animals, and humans. This study highlights an increasing distribution of tick-associated Borrelia burgdorferi, likely driven by accelerated tick population increases in response to climate change coupled with tick dispersal via migratory birds. This updated catalogue helps in compiling all tick species responsible for the transmission of B. burgdorferi across the globe. Gaps in research exist on Borrelia burgdorferi in continents such as Asia and Africa, and in considering environmentally friendly vector control strategies in Europe and North America.

An analysis of companion animal tick encounters as revealed by photograph-based crowdsourced data

Background

Community science is increasingly utilized to track important vectors of companion animal disease, providing a scalable, cost‐effective strategy for identifying new foci, changing phenology, and disease prevalence across wide geographies.

Objectives

We examined photographs of ticks found attached to predominately dogs and cats reported to a photograph‐based tick surveillance program to identify potential areas for improvements in tick prevention education and risk intervention.

Methods

We compared estimated days of tick attachment using a Kruskal–Wallis one‐way analysis of variance, and a Pearson's chi‐square analysis of variance on the number of submissions by host type submitted for each season.

Results

The blacklegged tick (Ixodes scapularis) was the most common species reported (39.8%). Tick photographs submitted were almost entirely adults (89.5%), and ticks found on companion animals exhibited an estimated median engorgement time of 2.5 days. Ixodes scapularis displayed the highest median engorgement of the top tick species found feeding on companion animals (χ² = 98.96, p < 0.001). Ticks were spotted year‐round; during spring and summer, ticks collected from pets represented 15.4 and 12.8% of all submissions, but increased to 28.5 and 35.2% during autumn and winter, respectively.

Conclusions

Crowdsourced data reveal that mostly adult ticks are detected on pets, and they are found at a point in the blood‐feeding process that puts pets at heightened risk for disease transmission. The increase in proportion of ticks found on pets during colder months may reveal a critical knowledge gap amongst pet owners regarding seasonal activity of I. scapularis, a vector of Lyme disease, providing an opportunity for prevention‐education.

Human-tick encounters as a measure of tickborne disease risk in lyme disease endemic areas

Entomological measures have long served as proxies for human risk of Lyme disease (LD) and other tickborne diseases (TBDs) in endemic areas of the United States, despite conflicting results regarding the correlation between these measures and human disease outcomes. Using data from a previous TBD intervention study in Connecticut, Maryland and New York, we evaluated whether human-tick encounters can serve as an accurate proxy for risk of TBDs in areas where LD and other Ixodes scapularis-transmitted infections are common. Among 2,590 households consisting of 4,210 individuals, experiencing a tick encounter was associated with an increased risk of both self-reported (RR = 3.17, 95% CI: 2.05, 4.91) and verified TBD (RR = 2.60, 95% CI: 1.39, 4.84) at the household level. Household characteristics associated with experiencing any tick encounter were residence in Connecticut (aOR = 1.86, 95% CI: 1.38, 2.51) or New York (aOR = 1.66, 95% CI: 1.25, 2.22), head of household having a graduate level education (aOR = 1.46, 95% CI: 1.04, 2.08), owning a pet (aOR = 1.80, 95% CI: 1.46, 2.23) and a property size of 2 acres or larger (aOR = 2.30, 95% CI: 1.42, 3.70). Results for individual characteristics were similar to those for households. Future prevention studies in LD endemic areas should consider using human-tick encounters as a robust proxy for TBD risk.

Barriers to Effective Tick Management and Tick-Bite Prevention in the United States (Acari: Ixodidae)

Lyme and other tick-borne diseases are increasing in the United States. Development of tick control tools have focused primarily on the blacklegged tick, Ixodes scapularis Say. Application of acaricides or entomopathogenic fungal agents to kill host-seeking ticks or ticks on rodents can suppress I. scapularis abundance in residential landscapes, but evidence is lacking for impact on human tick bites or tick-borne disease. Similar studies remain limited for the lone star tick, Amblyomma americanum (L.). Other knowledge gaps include how well homeowners and pest control companies perform in the broadcast application of tick-killing products, relative to high efficacy reported in research studies, and the tick-killing potential of natural product formulations exempt from Environmental Protection Agency registration. Area-wide control based on preventing ticks from feeding on their main reproductive host, the white-tailed deer, can suppress populations of both I. scapularis and A. americanum. Some studies also suggest an impact on Lyme disease cases, but this needs to be further validated in larger-scale intervention studies. The effectiveness, scale, cost, and implementation of various tick management strategies are important considerations in efforts to reduce human tick encounters and tick-borne disease. Additional barriers include weak incentives for industry and academia to develop, test, and register new tick and pathogen control technologies, including vaccines targeting humans, tick reproductive hosts, or wildlife pathogen reservoirs. Solutions will need to be 'two-pronged': improving the tick and pathogen control toolbox and strengthening the public health workforce engaging in tick control at local and state levels.

Epidemiological and Clinicopathological Features of Anaplasma phagocytophilum Infection in Dogs: A Systematic Review

Anaplasma phagocytophilum is a worldwide emerging zoonotic tick-borne pathogen transmitted by Ixodid ticks and naturally maintained in complex and incompletely assessed enzootic cycles. Several studies have demonstrated an extensive genetic variability with variable host tropisms and pathogenicity. However, the relationship between genetic diversity and modified pathogenicity is not yet understood. Because of their proximity to humans, dogs are potential sentinels for the transmission of vector-borne pathogens. Furthermore, the strong molecular similarity between human and canine isolates of A. phagocytophilum in Europe and the USA and the positive association in the distribution of human and canine cases in the USA emphasizes the epidemiological role of dogs. Anaplasma phagocytophilum infects and survives within neutrophils by disregulating neutrophil functions and evading specific immune responses. Moreover, the complex interaction between the bacterium and the infected host immune system contribute to induce inflammatory injuries. Canine granulocytic anaplasmosis is an acute febrile illness characterized by lethargy, inappetence, weight loss and musculoskeletal pain. Hematological and biochemistry profile modifications associated with this disease are unspecific and include thrombocytopenia, anemia, morulae within neutrophils and increased liver enzymes activity. Coinfections with other tick-borne pathogens (TBPs) may occur, especially with Borrelia burgdorferi, complicating the clinical presentation, diagnosis and response to treatment. Although clinical studies have been published in dogs, it remains unclear if several clinical signs and clinicopathological abnormalities can be related to this infection.

Clinical Practice Guidelines by the Infectious Diseases Society of America (IDSA), American Academy of Neurology (AAN), and American College of Rheumatology (ACR): 2020 Guidelines for the Prevention, Diagnosis and Treatment of Lyme Disease

This evidence-based clinical practice guideline for the prevention, diagnosis, and treatment of Lyme disease was developed by a multidisciplinary panel representing the Infectious Diseases Society of America (IDSA), the American Academy of Neurology (AAN), and the American College of Rheumatology (ACR). The scope of this guideline includes prevention of Lyme disease, and the diagnosis and treatment of Lyme disease presenting as erythema migrans, Lyme disease complicated by neurologic, cardiac, and rheumatologic manifestations, Eurasian manifestations of Lyme disease, and Lyme disease complicated by coinfection with other tick-borne pathogens. This guideline does not include comprehensive recommendations for babesiosis and tick-borne rickettsial infections, which are published in separate guidelines. The target audience for this guideline includes primary care physicians and specialists caring for this condition such as infectious diseases specialists, emergency physicians, internists, pediatricians, family physicians, neurologists, rheumatologists, cardiologists and dermatologists in North America.

Prevalence and distribution of Anaplasma phagocytophilum in ticks collected from dogs in the United Kingdom

BACKGROUND

Anaplasma phagocytophilum is the etiological agent of canine granulocytic anaplasmosis in dogs and causes human granulocytic anaplasmosis (HGA). Tick-borne anaplasmosis has been recognised as an emerging zoonotic health concern worldwide. The aim of the present study was to determine the prevalence of A. phagocytophilum in ticks collected from dogs in the UK and map its distribution. Routine surveillance of tick-borne disease is essential as part of a "One Health" approach to infectious disease management.

METHODS

Tick DNA samples collected in 2015 as part of a large-scale tick surveillance programme were analysed using a previously validated diagnostic quantitative PCR for A. phagocytophilum.

RESULTS

PCR analysis indicated that 138 out of 2994 tick DNA samples analysed were positive for A. phagocytophilum, a prevalence of 4.6% (95% CI: 3.89-5.42). Among these 138 tick DNA samples, 131 were from Ixodes ricinus, six were from Ixodes hexagonus and one was from Ixodes canisuga. Three of the I. ricinus tick DNA samples positive for A. phagocytophilum DNA were also positive for Borrelia spp. DNA and one was positive for Babesia spp. DNA, indicating co-infection. The ticks positive for the pathogen DNA were found widely distributed throughout the UK.

CONCLUSIONS

These data provide important information on the prevalence and wide distribution of A. phagocytophilum in ticks infesting dogs within the UK.

Seroprevalence and Genotypic Analysis of Ehrlichia canis Infection in Dogs and Humans in Cauca, Colombia

Ehrlichia canis infections have been reported in humans in Venezuela and Costa Rica. In this study, 506 healthy residents and 114 dogs from four municipalities (Cauca, Colombia) were surveyed and blood samples collected. Antibodies to E. canis in human and canine sera were evaluated using the Tandem repeat protein 19 (TRP19) peptide ELISA and indirect immunofluorescence assay (IFA). Ehrlichia canis TRP19 antibodies were detected in only 1/506 human sera, but the single positive sample was negative by IFA. The majority (75/114; 66%) of dogs surveyed had antibodies to the E. canis TRP19 peptide by ELISA, and eight randomly selected sera were further confirmed by E. canis IFA. Genomic DNA samples obtained from 73 E. canis TRP19 ELISA-positive dog blood samples were examined by PCR targeting the 16S ribosomal ribonucleic acid (rRNA) gene. Ehrlichia canis 16S rRNA was amplified in 30 (41%) of the dogs, and 16 amplicons were selected for DNA sequencing, which confirmed that all were E. canis. A second PCR was performed on the 16 confirmed E. canis 16S rRNA PCR-positive samples to determine the TRP36 genotype by amplifying the trp36 gene. TRP36 PCR amplicon sequencing identified nine dogs infected with the U.S. E. canis TRP36 genotype (56%), one dog with the Brazilian genotype (6%), and six dogs with the Costa Rican genotype (38%). Moreover, these molecular genotype signatures were consistent with serologic analysis using TRP36 genotype-specific peptides. Notably, there was no serologic evidence of E. canis infection in humans, suggesting that E. canis infection in dogs in Cauca is not associated with zoonotic human infection.

Assessing Public Tick Identification Ability and Tick Bite Riskiness Using Passive Photograph-Based Crowdsourced Tick Surveillance

Tick identification is critical for assessing disease risk from a tick bite and for determining requisite treatment. Data from the University of Rhode Island's TickEncounter Resource Center's photo-based surveillance system, TickSpotters, indicate that users incorrectly identified their submitted specimen 83% of the time. Of the top four most commonly submitted tick species, western blacklegged ticks (Ixodes pacificus Cooley & Kohls [Ixodida: Ixodidae]) had the largest proportion of unidentified or misidentified submissions (87.7% incorrectly identified to species), followed by lone star ticks (Amblyomma americanum Linneaus [Ixodida: Ixodidae]; 86.8% incorrect), American dog ticks (Dermacentor variabilis Say [Ixodida: Ixodidae]; 80.7% incorrect), and blacklegged ticks (Ixodes scapularis Say [Ixodida: Ixodidae]; 77.1% incorrect). More than one quarter of participants (26.3%) submitted photographs of ticks that had been feeding for at least 2.5 d, suggesting heightened risk. Logistic regression generalized linear models suggested that participants were significantly more likely to misidentify nymph-stage ticks than adult ticks (odds ratio [OR] = 0.40, 95% confidence interval [CI]: 0.23, 0.68, P < 0.001). Ticks reported on pets were more likely to be identified correctly than those found on humans (OR = 1.07, 95% CI: 1.01-2.04, P < 0.001), and ticks feeding for 2.5 d or longer were more likely to be misidentified than those having fed for one day or less (OR = 0.43, 95% CI: 0.29-0.65, P < 0.001). State and region of residence and season of submission did not contribute significantly to the optimal model. These findings provide targets for future educational efforts and underscore the value of photograph-based tick surveillance to elucidate these knowledge gaps.

Characterization of microbiota diversity of engorged ticks collected from dogs in China

BACKGROUND

Ticks are one of the most common external parasites in dogs, and are associated with the transmission of a number of major zoonoses, which result in serious harm to human health and even death. Also, the increasing number of pet dogs and pet owners in China has caused concern regarding human tick-borne illnesses. Accordingly, studies are needed to gain a complete understanding of the bacterial composition and diversity of the ticks that parasitize dogs.

OBJECTIVES

To date, there have been relatively few reports on the analysis of the bacterial community structure and diversity in ticks that parasitize dogs. The objective of this study was to investigate the microbial composition and diversity of parasitic ticks of dogs, and assessed the effect of tick sex and geographical region on the bacterial composition in two tick genera collected from dogs in China.

METHODS

A total of 178 whole ticks were subjected to a 16S ribosomal RNA (rRNA) next generation sequencing analysis. The Illumina MiSeq platform targeting the V3-V4 region of the 16S rRNA gene was used to characterize the bacterial communities of the collected ticks. Sequence analysis and taxonomic assignment were performed using QIIME 2 and the GreenGene database, respectively. After clustering the sequences into taxonomic units, the sequences were quality-filtered and rarefied.

RESULTS

After pooling 24 tick samples, we identified a total of 2,081 operational taxonomic units, which were assigned to 23 phyla and 328 genera, revealing a diverse bacterial community profile. The high, moderate and low prevalent taxa include 46, 101, and 182 genera, respectively. Among them, dominant taxa include environmental bacterial genera, such as Psychrobacter and Burkholderia. Additionally, some known tick-associated endosymbionts were also detected, including Coxiella, Rickettsia, and Ricketssiella. Also, the potentially pathogenic genera Staphylococcus and Pseudomonas were detected in the tick pools. Moreover, our preliminary study found that the differences in microbial communities are more dependent on the sampling location than tick sex in the tick specimens collected from dogs.

CONCLUSIONS

The findings of this study support the need for future research on the microbial population present in ticks collected from dogs in China.

Love the ones you're with: Characteristics and behaviour of Maryland pets and their owners in relation to tick encounters

We conducted a cross-sectional study to evaluate associations between pet characteristics and behaviours and risk of tick encounters among pets and pet owners. We defined a tick encounter as ticks found crawling on or attached to a pet or pet owner. Information about pet characteristics, interactions between owners and pets, and tick encounters were captured through an online survey. Associations were evaluated using univariate and multivariable analyses. In univariate analysis, walking dogs only on pavement reduced risk of tick encounter among owners (prevalence ratio (PR) = 0.51, 95% confidence interval (CI): 0.30, 0.84). Having a dog or cat that hunted small animals increased risk of tick encounter among owners (PR = 1.66, 95% CI: 1.30, 2.13; PR = 1.57, 95% CI: 1.05, 2.34, respectively). No direct interactions between owners and pets (e.g., pets sleeping on owners' beds) were associated with increased risk of tick encounters among owners. In multivariable analysis among dog owners, having a pet with a tick encounter within the last six months was associated with increased risk of owner tick encounter (adjusted odds ratio (aOR) = 4.17, 95% CI: 2.94, 5.92); in addition, having a dog that hunts small animals was associated with increased risk of owner tick encounter (aOR = 1.97, 95% CI: 1.25, 3.11). These results suggest that the location of pet-owner interactions may be more important than the type of interactions. Pet owners should avoid tick habitat with pets; when that is not possible, proper use of tick preventive products for pets, wearing repellents by owners and conducting tick checks for both pets and owners is critical for prevention of tick encounters and tick-borne disease.

Detection of Tick-Borne Pathogens in Ticks from Dogs and Cats in the Yamagata Prefecture of Japan in 2018

Companion animals can become infected with tick-borne diseases (TBDs) becoming a reservoir for human transfer, thereby damaging human health. To evaluate whether companion animals are infested with ticks harboring human TBD pathogens, we detected TBD pathogens in ticks collected from dogs and cats brought to animal hospitals in the Yamagata prefecture of Japan. An investigation of 164 adult ticks collected from 88 dogs and 41 cats between March and July 2018 revealed that this region was dominated by three tick species, Ixodes ovatus (n = 95, 57.9%), Ixodes nipponensis (n = 37, 22.6%) and Haemaphysalis flava (n = 10, 6.1%). To evaluate their pathogenic potential, we went on to test each tick for spotted fever group rickettsiae, Lyme disease borreliae, relapsing fever borreliae, tick-borne encephalitis virus, and Huaiyangshan banyangvirus (formerly SFTS virus). Our results identified two I. ovatus ticks infected with Borrelia miyamotoi, which causes emerging relapsing fever; several I. nipponensis ticks infected with Rickettsia monacensis, which cause rickettsiosis; and several Ixodes persulcatus ticks infected with Rickettsia helvetica, which can also cause rickettsiosis. These results suggest that dogs and cats, and veterinary professionals and pet owners, in the Yamagata prefecture have some risk of exposure to several TBDs. This means that there should be continuous monitoring and reporting of TBDs, even those known to be uncommon in Japan, in both companion animals and humans to ensure the health and safety of both humans and animals in Japan.

Context matters: Contrasting behavioral and residential risk factors for Lyme disease between high-incidence states in the Northeastern and Midwestern United States

The dynamics of zoonotic vector-borne diseases are determined by a complex set of parameters including human behavior that may vary with socio-ecological contexts. Lyme disease is the most common vector-borne disease in the United States. The Northeast and upper Midwest are the regions most affected - two areas with differing levels of urbanization and differing sociocultural settings. The probability of being infected with Lyme disease is related to the risk of encounters with Ixodes scapularis ticks infected with Borrelia burgdorferi sensu lato, which reflects both the environmental tick hazard and human behaviors. Herein, we compare behavioral and peridomestic risk factors perceived to influence the risk for human-tick encounters between two high-incidence states in the Northeast (New York and New Jersey) and one high-incidence state in the Midwest (Wisconsin). We used a smartphone application, The Tick App, as a novel survey tool, during spring and summer of 2018. Adaptive human behavior was identified in the relationship between outdoor activities and the use of methods to prevent tick bites. More frequent recreational outdoor activities and gardening (a peridomestic activity) were associated with a 1.4-2.3 times increased likelihood of using personal protective measures to prevent tick bites, when accounting for demographics and previous Lyme diagnosis. Most outdoor activities were more frequently reported by participants from the Midwest (n = 697), representing an older demographic, than the Northeast (n = 396). Participants from the Northeast were less likely to report use of personal protective measures to prevent tick bites, but a larger proportion of participants from the Northeast reported application of environmental pesticides targeting ticks or mosquitoes or other insects on their property (34 % of 279 versus 22 % of 616 participants) and interventions to reduce the presence of peridomestic deer compared to participants from the Midwest (e.g. 20 % of 278 versus 7% of 615 participants reported having a deer proof fence). Participants from the Midwest were more likely to kill rodents on their property (28 % versus 13 %). These differences illustrate the need for further assessment of personal behavior and tick exposure in these two Lyme disease-endemic regions to aid in targeted public health messaging to reduce tick-borne diseases.

Emerging Tick-Borne Diseases

Increases in tick-borne disease prevalence and transmission are important public health issues. Efforts to control these emerging diseases are frustrated by the struggle to control tick populations and to detect and treat infections caused by the pathogens that they transmit. This review covers tick-borne infectious diseases of nonrickettsial bacterial, parasitic, and viral origins. While tick surveillance and tracking inform our understanding of the importance of the spread and ecology of ticks and help identify areas of risk for disease transmission, the vectors are not the focus of this document. Here, we emphasize the most significant pathogens that infect humans as well as the epidemiology, clinical features, diagnosis, and treatment of diseases that they cause. Although detection via molecular or immunological methods has improved, tick-borne diseases continue to remain underdiagnosed, making the scope of the problem difficult to assess. Our current understanding of the incidence of tick-borne diseases is discussed in this review. An awareness of the diseases that can be transmitted by ticks in specific locations is key to detection and selection of appropriate treatment. As tick-transmitted pathogens are discovered and emerge in new geographic regions, our ability to detect, describe, and understand the growing public health threat must also grow to meet the challenge.

Tick-borne pathogens in ticks collected from dogs, Latvia, 2011-2016

BACKGROUND

Different tick species are able to transmit different pathogens, and tick-borne diseases are of substantial concern worldwide for both humans and animals. Environmental changes and changes in the range of tick species, including Dermacentor reticulatus in Europe, can affect the spread of zoonotic pathogens. The aim of this study was to investigate the prevalence of the tick-borne pathogens in ticks removed from dogs in Latvia, and to explore possible changes between years 2011 and 2016.

RESULTS

In 2011, only Ixodes ticks (221 Ixodes ricinus and 22 Ixodes persulcatus) were collected from dogs, while in 2016 tick samples belonged to Ixodes ricinus (360), Ixodes persulcatus (2) and Dermacentor reticulatus (27) species. In total, 35.8 and 40.0% of adult ticks were pathogen-positive in 2011 and 2016, respectively; the difference was not statistically significant (P > 0.05). The molecular analysis indicated the presence of 13 tick-borne microorganisms; the most prevalent pathogen was Rickettsia, followed by Borrelia burgdorferi sensu lato group spirochetes, Anaplasma phagocytophilum and Babesia species. Borrelia miyamotoi was also present. A co-infection with two and three tick-borne pathogens was detected in 7.9 and 7.4% of Ixodes ricinus and Dermacentor reticulatus, respectively. The results of this study confirmed that the spread of novel vectors could bring additional risk of exposure to novel emerging pathogens to pets and their owners, as both Babesia canis and Rickettsia raoultii were shown to be highly associated with Dermacentor reticulatus ticks in Latvia.

CONCLUSIONS

This study demonstrates the potential danger from the inadvertent introduction of novel disease pathogens and vectors. Awareness of co-infections and Dermacentor reticulatus-related pathogens needs to be increased.

2019 AAFP Feline Zoonoses Guidelines

AIM

The overarching purpose of the 2019 AAFP Feline Zoonoses Guidelines (hereafter referred to as the 'Guidelines') is to provide accurate information about feline zoonotic diseases to owners, physicians and veterinarians to allow logical decisions to be made concerning cat ownership.

SCOPE AND ACCESSIBILITY

The Panelists are physicians and veterinarians who worked closely together in an attempt to make these Guidelines a document that can be used to support the International One Health movement. This version of the Guidelines builds upon the first feline zoonosis panel report, published in 2003 ( catvets.com/guidelines ), and provides an updated reference list and recommendations. Each of the recommendations received full support from every Panelist. Primary recommendations are highlighted in a series of 'Panelists' advice' boxes.

Canine vector-borne disease: mapping and the accuracy of forecasting using big data from the veterinary community

Diagnosis, treatment, and prevention of vector-borne disease (VBD) in pets is one cornerstone of companion animal practices. Veterinarians are facing new challenges associated with the emergence, reemergence, and rising incidence of VBD, including heartworm disease, Lyme disease, anaplasmosis, and ehrlichiosis. Increases in the observed prevalence of these diseases have been attributed to a multitude of factors, including diagnostic tests with improved sensitivity, expanded annual testing practices, climatologic and ecological changes enhancing vector survival and expansion, emergence or recognition of novel pathogens, and increased movement of pets as travel companions. Veterinarians have the additional responsibility of providing information about zoonotic pathogen transmission from pets, especially to vulnerable human populations: the immunocompromised, children, and the elderly. Hindering efforts to protect pets and people is the dynamic and ever-changing nature of VBD prevalence and distribution. To address this deficit in understanding, the Companion Animal Parasite Council (CAPC) began efforts to annually forecast VBD prevalence in 2011. These forecasts provide veterinarians and pet owners with expected disease prevalence in advance of potential changes. This review summarizes the fidelity of VBD forecasts and illustrates the practical use of CAPC pathogen prevalence maps and forecast data in the practice of veterinary medicine and client education.

Assessing Effectiveness of Recommended Residential Yard Management Measures Against Ticks

Public health authorities recommend a range of nonchemical measures to control blacklegged ticks Ixodes scapularis Say, 1821 (Ixodida: Ixodidae) in residential yards. Here we enumerate these recommendations and assess their relationship to larval tick abundance in 143 yards in Dutchess County, New York, an area with high Lyme disease incidence. We examined the relationship between larval tick abundance and eight property features related to recommendations from public health agencies: presence or absence of outdoor cats, wood piles, trash, stone walls, wood chip barriers separating lawn from adjacent forest, bird feeders, fencing, and prevalence of Japanese barberry (Berberis thunbergii DC [Ranunculales: Berberidaceae]). We assessed abundance of larval ticks using two methods, flagging for questing ticks and visual examination of ticks on white-footed mice Peromyscus leucopus Rafinesque, 1818 (Rodentia: Cricetidae). More questing larvae were found in yards where trash or stone walls were present. These effects were less pronounced as forest area increased within the yard. Counts of larvae per mouse were lower in properties with >75% of the yard fenced than in properties with less fencing. We find partial support for recommendations regarding trash, stone walls, and fencing. We did not detect effects of outdoor cats, bird feeders, barriers, wood piles, or Japanese barberry. There was low statistical power to detect effects of ground barriers (gravel, mulch, or woodchip), which were present in only two properties.

Human tularaemia associated with exposure to domestic dogs-United States, 2006-2016

Dogs have been implicated in the zoonotic transmission of numerous pathogens. Whereas cats are known to transmit Francisella tularensis to humans via bite and other routes, the role of dogs in facilitating infection is much less understood. We reviewed tularaemia case investigation records collected through national surveillance during 2006-2016 to summarize those with dog involvement, characterize the nature of dog-related exposure and describe associated clinical characteristics. Among 1,814 human tularaemia cases, 735 (41%) supplemental case investigation records were available for review; and of those, 24 (3.3%) were classified as dog-related. Median age of patients was 51 years (range: 1-82); 54% were female. Two thirds (67%) of cases presented with ulceroglandular/glandular tularaemia; pneumonic (13%) and oropharyngeal (13%) illness occurred less frequently. Dog-related exposures were classified as follows: direct contact via bite, scratch or face snuggling/licking (n = 12; 50%); direct contact with dead animals retrieved by domestic dogs (n = 8; 33%); and contact with infected ticks acquired from domestic dogs (n = 4; 17%). Prevention of dog-related tularaemia necessitates enhanced tularaemia awareness and tick avoidance among pet owners, veterinarians, health care providers and the general public.

Molecular detection and characterization of Anaplasma platys and Ehrlichia canis in dogs from northern Colombia

Ehrlichia canis and Anaplasma platys are intracellular tick-transmitted bacteria that infect dogs; there is evidence for limited zoonotic potential as well. The prevalence of E. canis in Colombia has been evaluated in different regions; however little is known about the prevalence or distribution of A. platys. Neither pathogen has been studied in the Magdalena region, thus the purpose of our study was to assess the prevalence of these pathogens in dogs attending veterinary clinics from the cities of Santa Marta and Ciénaga, and to assess possible associated risk factors for infection. A. platys and E. canis infections in blood were evaluated by Taqman PCR assays. E. canis was detected in 26/170 (15.3%, 95% CI 10.4%-21.8%) and A. platys in 34/168 (20.2%, 95% CI 14.6%-27.3%) of all dogs tested. Eleven dogs (6.5%, 95% CI 3.4-11.7%) were coinfected with both pathogens. Sequencing results showed low diversity within E. canis and within A. platys strains, however a strain of E. canis detected in our study area is genetically distinct from strains reported in another city of Colombia. Our results suggest that for A. platys, Santa Marta dogs were at greater risk than Ciénaga dogs, and that purebred dogs were at slightly lower risk in both areas. The confirmation of these pathogens in northern Colombia should cause concern for the possible co-transmission of these agents to humans or animals in the region.

2018 AAHA Infection Control, Prevention, and Biosecurity Guidelines*

A veterinary team’s best work can be undone by a breach in infection control, prevention, and biosecurity (ICPB). Such a breach, in the practice or home-care setting, can lead to medical, social, and financial impacts on patients, clients, and staff, as well as damage the reputation of the hospital. To mitigate these negative outcomes, the AAHA ICPB Guidelines Task Force believes that hospital teams should improve upon their current efforts by limiting pathogen exposure from entering or being transmitted throughout the hospital population and using surveillance methods to detect any new entry of a pathogen into the practice. To support these recommendations, these practice-oriented guidelines include step-by-step instructions to upgrade ICPB efforts in any hospital, including recommendations on the following: establishing an infection control practitioner to coordinate and implement the ICPB program; developing evidence-based standard operating procedures related to tasks performed frequently by the veterinary team (hand hygiene, cleaning and disinfection, phone triage, etc.); assessing the facility’s ICPB strengths and areas of improvement; creating a staff education and training plan; cataloging client education material specific for use in the practice; implementing a surveillance program; and maintaining a compliance evaluation program. Practices with few or no ICPB protocols should be encouraged to take small steps. Creating visible evidence that these protocols are consistently implemented within the hospital will invariably strengthen the loyalties of clients to the hospital as well as deepen the pride the staff have in their roles, both of which are the basis of successful veterinary practice.

Detection of Rickettsia monacensis and Rickettsia amblyommatis in ticks collected from dogs in Costa Rica and Nicaragua

The neotropical climate of Central America provides ideal conditions for ticks, which may transmit several human pathogens, including spotted-fever group Rickettsia. Dogs may act as sentinels or reservoirs for human tick-borne diseases due to shared tick species. Here, ticks were collected from 680 client-owned dogs in Nicaragua and Costa Rica, and a total of 316 tick pools were investigated for Rickettsia infection by quantitative real-time PCR (qPCR) targeting the gltA gene. Subsequently, up to six further genomic targets (16S rDNA, gltA, sca4, ompA, ompB and the 23S-5S intergenic spacer) were investigated for Rickettsia species determination. The predominant tick species was Rhipicephalus sanguineus sensu lato (s.l.) (19.9% of dogs infested in Costa Rica, 48.0% in Nicaragua), followed by Ixodes boliviensis (3.1% in Costa Rica / none in Nicaragua) and Amblyomma ovale (4.8% in Costa Rica, 0.9% in Nicaragua). In total, 22 of 316 tick pools containing 60 of 1023 individual ticks were Rickettsia-positive as determined by qPCR, resulting in a minimum infection rate (MIR) of 2.2%. In detail, MIR in Rh. sanguineus s.l. was 0.7% (7/281 pools), in I. boliviensis 33.3% (12/13 pools) and in A. ovale 9.7% (3/22 pools). For 11 of 12 positive I. boliviensis pools and one of six positive Rh. sanguineus s.l. pools, the species could be determined as R. monacensis. R. amblyommatis was identified in one Rh. sanguineus s.l. pool from Costa Rica and one A. ovale pool from Nicaragua. Nine of 12 R. monacensis-positive tick pools were collected in San Rafael de Heredia, Costa Rica, indicating a high local occurrence in this area. This study supports recent evidence that R. monacensis is present on the American continent. Its high local occurrence among dog-associated I. boliviensis, which may also parasitize humans, in Costa Rica gives cause for concern, as R. monacensis is also pathogenic to humans.

Progress, challenges, and the role of public engagement to improve tick-borne disease literacy

Vector-borne diseases have increased worldwide, facilitated by globalization and variations in climate. Tick and tick-borne disease researchers, veterinarians, medical practitioners, and public health specialists are working to share their expertise on tick ecology, disease transmission, diagnostics, and treatment in order to control tick-borne epidemics and potential pandemics. This review will be a brief overview of the current status of tick-borne diseases, challenges on the scientific and public fronts, and the role of public engagement in improving citizen education within the context of ticks and tick-borne disease research.

Frequent Exposure to Many Hunting Dogs Significantly Increases Tick Exposure

Certain professionals have more exposure to animals and therefore an increased risk of zoonoses. Professional hunting dog caretakers work with upwards of 50 dogs and are exposed to zoonoses through exposure to multiple potentially infectious canine secretions or excretions, as well as to the ticks that dogs carry. Dog caretakers reported having found embedded ticks on their bodies 5.83 times more than environment-only controls. Zoonotic Lyme disease, first in the United States for morbidity due to a vector-borne infection, has dramatically expanded its geographic range over the last two decades. This finding emphasizes the increased risk of tick-borne diseases, including Lyme disease, based on dog exposure and in areas of disease emergence.

Clinical presentation of Lyme disease in the higher-risk region of Quebec: a retrospective descriptive study

BACKGROUND

Lyme disease is emerging in Canada. This study aimed to describe the use of serologic testing for the disease in the La Pommeraie health region in southern Quebec between 2012 and 2015 and to describe the clinical presentation of laboratory-confirmed cases.

METHODS

The medical charts of all patients investigated for Lyme disease at the Brome-Missisquoi-Perkins Hospital's laboratory between 2012 and 2015 were reviewed for results of serologic testing. Laboratory diagnosis was based on 2-tiered testing: cases had to have positive results of both the enzyme immunoassay and the Western blot test (IgM or IgG). We collected data on clinical presentation for patients assessed at the hospital or at the La Pommeraie Family Medicine Unit.

RESULTS

Over the study period, 720 patients were investigated for Lyme disease. There was a more than fivefold increase in requests for serologic testing from 2012 (53) to 2015 (273). The number of confirmed cases increased from 2012 (3) to 2013 (19) and remained stable thereafter (19 in 2014, 18 in 2015). Fifty patients were positive for IgM with or without IgG positivity, and 9 patients were IgG-positive only. Chart reviews were completed for 278 of the 720 patients, including 38 of the 59 laboratory-confirmed cases. Among the 29 IgM-positive patients, the most common symptoms were fever (17 patients [59%]), fatigue (14 [48%]), myalgia (12 [41%]) and headaches (10 [34%]). Twenty-three (79%) had some cutaneous manifestation, including specifically erythema migrans (14 [48%]). A tick bite was reported by 11 patients (38%). Of the 44 patients in the entire study population who presented with erythema migrans, 15 (34%) had confirmed Lyme disease.

INTERPRETATION

Requests for serologic testing for Lyme disease increased in the La Pommeraie health region over recent years. Cutaneous manifestations, fever and myalgia were the most common symptoms of IgM-positive cases. Most patients did not report a tick bite.

Molecular survey of neglected bacterial pathogens reveals an abundant diversity of species and genotypes in ticks collected from animal hosts across Romania

Background

Ticks are transmitting a wide range of bacterial pathogens that cause substantial morbidity and mortality in domestic animals. The full pathogen burden transmitted by tick vectors is incompletely studied in many geographical areas, and extensive studies are required to fully understand the diversity and distribution of pathogens transmitted by ticks.

Results

We sampled 824 ticks of 11 species collected in 19 counties in Romania. Ticks were collected mainly from dogs, but also from other domestic and wild animals, and were subjected to molecular screening for pathogens. Rickettsia spp. was the most commonly detected pathogen, occurring in 10.6% (87/824) of ticks. Several species were detected: Rickettsia helvetica, R. raoultii, R. massiliae, R. monacensis, R. slovaca and R. aeschlimannii. A single occurrence of the zoonotic bacterium Bartonella vinsonii berkhoffii was detected in a tick collected from a dog. Anaplasma phagocytophilum occurred in four samples, and sequences similar to Anaplasma marginale/ovis were abundant in ticks from ruminants. In addition, molecular screening showed that ticks from dogs were carrying an Ehrlichia species identical to the HF strain as well as the enigmatic zoonotic pathogen “Candidatus Neoehrlichia mikurensis”. An organism similar to E. chaffeensis or E. muris was detected in an Ixodes ricinus collected from a fox.

Conclusions

We describe an abundant diversity of bacterial tick-borne pathogens in ticks collected from animal hosts in Romania, both on the level of species and genotypes/strains within these species. Several findings were novel for Romania, including Bartonella vinsonii subsp. berkhoffii that causes bacteremia and endocarditis in dogs. “Candidatus Neoehrlichia mikurensis” was detected in a tick collected from a dog. Previously, a single case of infection in a dog was diagnosed in Germany. The results warrant further studies on the consequences of tick-borne pathogens in domestic animals in Romania.

Electronic supplementary material

The online version of this article (10.1186/s13071-018-2756-1) contains supplementary material, which is available to authorized users.