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The wild life of ticks: Using passive surveillance to determine the distribution and wildlife host range of ticks and the exotic Haemaphysalis longicornis, 2010–2021

Parasites & Vectors volume 15, Article number: 331 (2022) Cite this article

Abstract

Background

We conducted a large-scale, passive regional survey of ticks associated with wildlife of the eastern United States. Our primary goals were to better assess the current geographical distribution of exotic Haemaphysalis longicornis and to identify potential wild mammalian and avian host species. However, this large-scale survey also provided valuable information regarding the distribution and host associations for many other important tick species that utilize wildlife as hosts.

Methods

Ticks were opportunistically collected by cooperating state and federal wildlife agencies. All ticks were placed in the supplied vials and host information was recorded, including host species, age, sex, examination date, location (at least county and state), and estimated tick burden. All ticks were identified to species using morphology, and suspect H. longicornis were confirmed through molecular techniques.

Results

In total, 1940 hosts were examined from across 369 counties from 23 states in the eastern USA. From these submissions, 20,626 ticks were collected and identified belonging to 11 different species. Our passive surveillance efforts detected exotic H. longicornis from nine host species from eight states. Notably, some of the earliest detections of H. longicornis in the USA were collected from wildlife through this passive surveillance network. In addition, numerous new county reports were generated for Amblyomma americanum, Amblyomma maculatum, Dermacentor albipictus, Dermacentor variabilis, and Ixodes scapularis.

Conclusions

This study provided data on ticks collected from animals from 23 different states in the eastern USA between 2010 and 2021, with the primary goal of better characterizing the distribution and host associations of the exotic tick H. longicornis; however, new distribution data on tick species of veterinary or medical importance were also obtained. Collectively, our passive surveillance has detected numerous new county reports for H. longicornis as well as I. scapularis. Our study utilizing passive wildlife surveillance for ticks across the eastern USA is an effective method for surveying a diversity of wildlife host species, allowing us to better collect data on current tick distributions relevant to human and animal health.

Background

Ticks and tick-borne diseases constitute a major threat to human and animal health and are rapidly becoming recognized as a global One Health issue. Numerous underlying factors such as climate change, habitat fragmentation, and increased globalization with the movement of humans and animals to new areas of the world all promote the geographical expansion of multiple tick species and their pathogens [1,2,3,4]. The spread of non-native parasites is a significant concern for disease emergence and native species conservation; therefore, it is of extreme importance to identify these exotic ticks and their pathogens and take effective steps to prevent their dispersal and establishment, which presents enormous challenges to both conservation and international commerce [5,6,7]. In the case of exotic ticks, the detection and management of these species often fail for a variety of reasons resulting from their unique and often complex life history traits and ability to utilize a variety of domestic, livestock, and wildlife hosts.

Passive surveillance is a commonly used method by health officials and researchers to investigate the geographical distribution and host associations of ticks. Many of these passive surveillance strategies involve image submissions of ticks for expert, artificial intelligence, or crowdsourced identification [8,9,10,11], the use of electronic patient records from companion animals [12], and most commonly whole tick submissions from citizen scientists, veterinarians, and physicians [13,14,15,16,17,18]. Only a few published studies using passive surveillance have included ticks collected from wildlife hosts, and of those studies, most were statewide surveys, leaving gaps in our understanding of the regional distribution of ticks relevant to both human and animal health [19,20,21,22,23].

A newly recognized tick of One Health significance in the United States is the Asian longhorned tick, Haemaphysalis longicornis (Acari: Ixodidae). Native to East Asia, H. longicornis has become invasive to several regions of the world including Australia, New Zealand, and most recently the USA, having first been detected outside of quarantine zones at USA ports of entry in 2017 on an Icelandic ewe (Ovis aries) from New Jersey [24,25,26]. However, reexaminations of archived specimens revealed the presence of H. longicornis in the USA on several wildlife species from multiple states dating as early as 2010 on a white-tailed deer (Odocoileus virginianus) from West Virginia (present study) [27]. This case of H. longicornis on wildlife almost a decade prior to the tick being detected on livestock signals a dire need for a comprehensive tick survey of wildlife hosts within the United States.

Within the established range, H. longicornis infests a variety of mammalian and avian species (including companion animals, livestock, and wildlife) and is found in a variety of geographical and climatic habitats [25,26,27,28]. Since the initial discovery outside of quarantine zones, H. longicornis has now been detected in 17 states and has become an increasing human and veterinary health concern, as it is either a suspected or confirmed vector for several pathogens. Recent laboratory infection trials have indicated H. longicornis as a competent vector for Rickettsia rickettsii, the causative agent for Rocky Mountain spotted fever and Heartland virus, but experimentally it was not a suitable vector for Borrelia burgdorferi sensu stricto or Anaplasma phagocytophilum Ap-Ha, the causative agents for Lyme disease and human granulocytic anaplasmosis, respectively [29,30,31,32]. However, despite the experimental transmission studies, several medically important pathogens have been detected in environmentally collected host-seeking H. longicornis including B. burgdorferi, A. phagocytophilum Ap-Ha (both detected in populations from Pennsylvania [33, 34]), and Rickettsia felis and Bourbon virus (detected in populations from Virginia [35, 36]). Of veterinary importance, native genotypes of the white-tailed deer variant of A. phagocytophilum (Ap-1) and a Hepatozoon species have been detected in host-seeking H. longicornis from Virginia [35]. Additionally, H. longicornis is a confirmed vector for an exotic protozoan parasite, Theileria orientalis Ikeda, the cause of cattle mortality at a farm in Virginia; however, infections have been noted to be widespread in Virginia and West Virginia [37,38,39]. Finally, there have been multiple reports of intense infestations on cattle resulting in mortality possibly by exsanguination in North Carolina, and previous studies report severe H. longicornis infestations on wildlife species [40,41,42].

Currently published surveillance studies for H. longicornis in the USA are limited geographically and as a result are unlikely to capture the potential wildlife host range utilized by H. longicornis [35, 40, 41, 43,44,45]. In addition, habitat suitability models primarily focusing on climatic and geographical variables to predict the potential range of H. longicornis have been reported, but they were built around limited datasets of H. longicornis occurrences (rather than established population data) and therefore may not accurately depict all suitable habitats in the USA [46,47,48]. In this study, we conducted a large-scale, passive regional survey of ticks associated with wildlife of the eastern USA. Our primary goals were to better assess the current geographical distribution of exotic H. longicornis and to identify potential wild mammalian and avian host species. However, this large-scale survey also provided valuable information regarding the distribution and host associations for many other tick species of medical and veterinary importance that utilize wildlife as hosts.

Methods

Wildlife host surveillance for H. longicornis started in fall 2017 after the initial detection of this tick outside of quarantine zones in New Jersey and is currently ongoing; however, data collected after 2021 are not included in this manuscript [24, 49]. Tick collection kits consisting of 15-ml vials pre-filled with 70% ethanol, forceps, collection instructions, blank labels, and data sheets were shared with state and federal wildlife agencies that were members of the Southeastern Cooperative Wildlife Disease Study (SCWDS) and with states currently reporting H. longicornis infestations. Participating agencies were asked to disseminate tick collection kits and instructions to agency staff members. Ticks were collected from wildlife by utilizing a variety of approaches including wildlife during health surveys, car strike kills, nuisance animal removal, hunter checks, or during sample collection for other ongoing studies. All ticks were placed in the supplied vials, and general information such as host species, age, sex, examination date, location (at least county and state), and estimated tick burden were recorded. Ticks and corresponding data sheets were then submitted to SCWDS for identification. In addition, ticks were also opportunistically collected from carcasses submitted for necropsy to SCWDS from member states as part of wildlife mortality investigations.

Upon receipt, tick vials were given a unique identification number and screened for Haemaphysalis sp. ticks using morphology [50]. All ticks were examined by at least two people, and suspect H. longicornis were confirmed using polymerase chain reaction (PCR) targeting the 16S rRNA gene, analyzed using restriction fragment length polymorphisms (RFLPs), and sequenced as described by Thompson et al. [51]. Specimens of H. longicornis collected from either a new host, new county, or new state were submitted to the National Veterinary Sciences Laboratory (NVSL) in Ames, Iowa, for morphological confirmation and archiving purposes. All other ticks in the vials were identified to species using morphology keys [50, 52,53,54,55,56]. Specimens that were damaged or in poor condition (i.e., missing capitulum or eviscerated) were identified to genus and life stage when possible. The data collected from this surveillance effort were reported to the United States Department of Agriculture Animal and Plant Health Inspection Service (USDA-APHIS) and presented in the monthly National Haemaphysalis longicornis (Asian longhorned tick) Situation Report [49]. A subset of these data were included in summary form in a previous report on the distribution of H. longicornis [27]. Established tick populations for county-level data were classified based on the Centers for Disease Control and Prevention (CDC) criteria of ≥ 6 individual ticks or > 1 life stage collected in a span of 1 year, with ticks collected from deer or small- or medium-sized mammals being acceptable to classify a county status [57, 58]. Classification of any new established counties was compared with previous data whenever available (National Arboviral Surveillance System ArboNET; https://wwwn.cdc.gov/Arbonet/) [58,59,60]. All analyses and data visualization were done using the R programming software (https://www.R-project.org/). Maps showing tick distributions and county classifications were generated using the ggmap package and network graphs showing tick–host associations were generated using the networkD3 package. All other graphs showing host submissions by state and proportion of tick species collected by month were generated using the ggplot2 package.

Since 1961, SCWDS has assisted various state and federal agencies in conducting herd health checks on white-tailed deer. As part of this work, ticks were collected and identified. These archived SCWDS tick specimens from 2010 to 2017 were also included in the study. No ticks included in this study were tested for pathogens, because most host-attached ticks could contain host blood, convoluting pathogen detection data (i.e., was the tick infected or was the host infected).

Results

In total, 1,940 hosts were examined from across 369 counties from 23 states in the eastern USA (Fig. 1, Additional files 1, 2). Although agencies were asked to collect from wildlife, a few submissions from domestic animals and humans were submitted, so these were also included in our study. White-tailed deer was the most frequently sampled host species (n = 1,371; 71%), followed by black bear (Ursus americanus; n = 226; 12%), elk (Cervus canadensis; n = 96; 5%), mule deer (Odocoileus hemionus; n = 66; 3%), and wild turkey (Meleagris gallopavo; n = 42; 2%). Other wildlife species making up the remaining 10% of hosts sampled included woodchuck (Marmota monax; n = 22), spotted skunk (Spilogale putorius; n = 21), raccoon (Procyon lotor; n = 16), coyote (Canis latrans, n = 11), domestic dog (Canis lupus familiaris; n = 11), wild pig (Sus scrofa; n = 11), bobcat (Lynx rufus; n = 9), red fox (Vulpes vulpes; n = 6), Virginia opossum (Didelphis virginiana; n = 6), striped skunk (Mephitis mephitis; n = 5), gray fox (Urocyon cinereoargenteus; n = 2), and white-footed mouse (Peromyscus leucopus; n = 2). We received one submission each from a desert bighorn sheep (Ovis canadensis nelson), northern bobwhite (Collinus virginianus), red-backed vole (Clethrionomys sp.), red deer (Cervus elaphus), ruffed grouse (Bonasa umbellus), and woodland jumping mouse (Napaeozapus insignis). Ticks were received from a single cattle herd (Bos taurus); however, individual infested cattle were not counted. Finally, two submissions were received from humans and eight submissions were collected from an environmental source (Additional file 1).

Fig. 1
figure 1

Agency submissions, 2010–2021. Counties highlighted in gray indicate that at least one tick submission was received during the study. Inset represents states that submitted samples

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From these submissions, 20,626 ticks were collected and identified. Amblyomma americanum (n = 10,942; 53%) and Ixodes scapularis (n = 4,846; 24%) were the two most commonly collected species, followed by D. variabilis (n = 1,804; 9%), D. albipictus (n = 1,240; 6%), A. maculatum (n = 848; 4%), and H. longicornis (n = 451; 2%). The remaining 2% of tick species collected included Ixodes cookei (n = 201), Ixodes affinis (n = 38), Otobius megnini (n = 26), Ixodes texanus (n = 15), and Haemaphysalis leporispalustris (n = 1). A small number of ticks (one Amblyomma sp. and 202 Ixodes sp.) could not be identified to species due to missing morphological features (Additional file 1).

Our passive surveillance efforts detected the exotic H. longicornis from nine host species from eight states including Georgia, Kentucky, Maryland, New Jersey, North Carolina, Pennsylvania, Virginia, and West Virginia (Additional file 1, Fig. 2f). White-tailed deer (n = 41) and elk (n = 12) were the two host species most frequently detected with H. longicornis infestations, followed by domestic dog (n = 4), black bear (n = 2), and coyote (n = 2), with human, red fox, and Virginia opossum each having one detection (Fig. 3). Individual cows were not counted in this study; however, a herd in Pickens County, GA, was found to be infested with H. longicornis. Two submissions from environmental sources were also positive for H. longicornis. The passive surveillance resulted in many of the first county, state, and host reports for H. longicornis in the USA (Table 1). Notably, some of the most historical detections of H. longicornis in the USA were collected from wildlife through the SCWDS passive surveillance network, the earliest being a white-tailed deer from West Virginia in 2010 (previously misidentified as H. leporispalustris), as well as a black bear from Kentucky, a white-tailed deer from West Virginia, and a Virginia opossum from North Carolina in 2017 (additional specimens previously misidentified as H. leporispalustris). Based on CDC guidelines for established tick populations (≥ 6 ticks or > 1 life stage collected in a span of 1 year), 11 counties were classified as established, nine of which represent new counties including the furthest south detection of H. longicornis in the USA from Pickens County, GA [59] (Fig. 2f, Additional file 3).

Fig. 2
figure 2

Spatial data for individual tick species detected from surveillance between 2010 and 2021. Green counties indicate an established population as defined by the CDC. Orange counties indicate a new established classification for a county. Blue counties represent other detections made from the present study. A Amblyomma americanum; B Amblyomma maculatum; C Dermacentor albipictus; D Dermacentor variabilis; E Ixodes scapularis; F Haemaphysalis longicornis

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Fig. 3
figure 3

Tick–host associations by region. For all panels, the left axis represents hosts and the right axis represents tick species; links between the two axes depict the tick species that were collected from the different host groups. a Midwest (includes IL, IN, KS, MO, NE, OH); b Northeast (includes CT, DE, MA, MD, NJ, NY, PA, RI); c Mid-South Central (includes AR, LA, OK, TX); d Southeast (includes AL, FL, GA, KY, MS, NC, SC, TN, VA, WV)

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Table 1 First host, county, or state detections of Haemaphysalis longicornis through this passive wildlife agency surveillance effort, 2010–2021
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Of the five most abundant tick species collected, the most common species, A. americanum, was detected from 18 of the 23 sampled states and was found to be established in 115 different counties, including 30 new county reports [60]. It was not reported from the most northeastern, mid-western or southwestern regions of the sampled area (Fig. 2a, Additional file 3). Eleven different mammalian species and one avian species were infested with A. americanum. Ixodes scapularis was the second most common tick species collected and had a broad range. This tick was detected from all states that submitted specimens except for the most western sampled states (Nebraska, Kansas, Oklahoma, and Texas) and Illinois, and was classified as established in 91 different counties which included 34 new county reports (ArboNET, Additional file 3). Ixodes scapularis was collected from 14 mammalian host species and two avian host species. Similar to I. scapularis, both D. albipictus and D. variabilis had broad distributions; however, they were detected less frequently and from four mammalian host species and 14 mammalian host species, respectively. Amblyomma maculatum was detected primarily in the more southern and coastal states sampled on six mammalian host species; however, we also received specimens from counties outside of its previously reported range in central Kentucky, Nebraska, New Jersey, Virginia, and West Virginia [61]. (Figs. 2, 3). Ixodes affinis was identified from a small number of white-tailed deer from Florida and North Carolina. The spinose ear tick, O. megnini, was rarely detected in submissions from the Midwest. Finally, I. cookei and I. texanus were periodically collected in ticks submitted from medium-sized mammals (Additional file 1).

The monthly abundance of the five most commonly collected ticks was also characterized (Fig. 4). For the most part, the abundance of these species was consistent with what is currently described in the literature. Amblyomma americanum was collected year-round, with most collections in the summer and with peaks in March and August. Similarly, D. variabilis was primarily collected in the summer months. Both I. scapularis and D. albipictus were more commonly collected in the late fall and winter months. Finally, both H. longicornis and A. maculatum displayed similar trends, with a gradual increase in collections starting in the summer months and a peak in collections in September. Haemaphysalis longicornis also had a peak in collections in April, likely representing the end of its winter diapause.

Fig. 4
figure 4

General trends of monthly abundance of ticks collected during the study 2010—2021. Amblyomma americanum is represented by the red solid line; Amblyomma maculatum is represented by the yellow dashed line; Dermacentor albipictus is represented by the green long-dashed line; Dermacentor variabilis is represented by the teal long-dashed line; Haemaphysalis longicornis is represented by the blue dotted line; and Ixodes scapularis is represented by the pink dot-dashed line

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Discussion

This study provided data on ticks collected from animals from 23 different states in the eastern USA between 2010 and 2021, with the primary goal of better characterizing the distribution and host associations of the exotic tick H. longicornis. However, new data for several native tick species of veterinary or medical importance were also obtained. Collectively, our passive surveillance has detected numerous new established county reports for H. longicornis as well as I. scapularis. Over 1,900 wildlife and domestic hosts were sampled, representing 23 mammalian and three avian species; however, a majority of these hosts were from the families Cervidae (including elk, mule deer, red deer, white-tailed deer; n = 1,534) and Ursidae (black bear; n = 226), as wildlife agency personnel are often in close contact with these species. Nevertheless, it is important to note that this sampling bias skews the observed diversity and collection frequency to overrepresent those tick species and life stages that are most likely to feed on cervids and bears. In addition, 206 medium-sized mammals (i.e., bobcat, coyote, domestic dog, gray fox, red fox, raccoon, spotted and striped skunk, Virginia opossum, and woodchuck) were also sampled, providing some insight into the tick–host associations of these species. Our study utilizing passive wildlife surveillance for ticks across the eastern USA is an effective method for surveying a diversity of wildlife host species, allowing us to better collect widespread data on current tick distributions relevant to human and animal health.

Wildlife are important hosts for many tick species, as they can serve as maintenance hosts and potential disseminators, and in some cases wildlife species have facilitated increases in the range of tick species through natural movements, migration, or human-facilitated translocation [2, 4, 62]. For example, the increasing populations of white-tailed deer in the eastern USA have been linked to the increasing abundance and broader distribution of A. americanum [63], migratory birds have been implicated in the expansion of the range of I. scapularis [62], and the movement of large carnivores and domestic animals has been associated with the gradual northern expansion of D. variabilis [64]. Finally, both migratory birds and medium to large mammal species have been suggested to facilitate the expansion of A. maculatum [65, 66]. For exotic H. longicornis, it is still debated how this tick is spreading within the USA, though its initial introduction to the USA is believed to be via domestic animal and livestock movement [67, 68]. Furthermore, several of the tick species detected in this study are more common on wildlife than domestic species and are rarely detected via environmental detections [69]. For example, given certain life history traits, D. albipictus, H. leporispalustris, I. cookei, I. texanus, and O. megnini would likely not be detected in surveillance studies focusing on domestic animals or utilizing only environmental sampling. In addition, many wildlife species serve as reservoir hosts for many tick-borne pathogens relevant to human and animal health. By characterizing tick distributions via wildlife host sampling, we can begin to better predict areas of higher disease risk where vector and reservoir host co-occur.

Per current CDC guidelines, for a tick population to be classified as “established,” it requires the collection of ≥ 6 ticks or > 1 life stage within a single year, either from the environment or from deer and small- to medium-sized mammals; all else is considered “reported” [57, 70]. For our county classifications, we considered deer to include any cervid species and small- to medium -sized mammals to include anything smaller than a coyote. In general, the distributions of ticks and their host associations detected in this study were similar to what has been previously reported in the literature [10, 18, 19, 57, 65, 71,72,73,74,75]. Unfortunately, for certain tick species (e.g., A. maculatum, D. albipictus, and D. variabilis) there are currently limited data designating counties as reported versus established, and therefore we were unable to generate any new established county data for these species. However, with significantly more vector-borne disease cases being reported in the USA and the emphasis on surveillance, we expect similar large-scale datasets like the ArboNET I. scapularis data to become available [76].

Two species of Haemaphysalis were detected: the exotic Asian longhorned tick H. longicornis (n = 451), and the native rabbit tick H. leporispalustris (n = 1). Several studies that have been conducted in the USA after the initial detection of H. longicornis have documented a broad host range for H. longicornis; however, these studies were all focused in relatively small geographical areas (e.g., Connecticut, Pennsylvania, New Jersey, New York, or Virginia) [33, 35, 43, 45, 59]. Our passive geographically broad-scale surveillance for H. longicornis was an effective method for providing new and rapid data on the distribution of this tick in the USA. The passive surveillance efforts detected H. longicornis from nine host species (black bear, cow, coyote, domestic dog, elk, human, red fox, Virginia opossum, and white-tailed deer) from eight different states and resulted in some of the first county, state, and host collections in the USA. Although these data are compiled for the current study, our data were reported to the USDA in real time for inclusion in monthly situation reports [49]. When this tick was first detected in 2017, several studies were conducted to determine whether wildlife were infested, and either retrospective data were reviewed or archived ticks were examined, some of which were included in this study. The single H. leporispalustris was collected from a white-tailed deer in Georgia. Although this tick is commonly associated with lagomorphs and avian species, detection of this tick on deer is not uncommon; however, this highlights the importance of being able to distinguish these two morphologically similar Haemaphysalis species [75].

This study documents the earliest record of H. longicornis in the USA, which was collected from a white-tailed deer in 2010 in West Virginia, years before it was identified as established in North America [27]. Additionally, SCWDS-led tick surveillance efforts conducted during 2017, the same year it was initially detected in New Jersey, collected H. longicornis from additional wildlife species and new states (black bear from Kentucky and Virginia opossum from North Carolina), demonstrating the important role of wildlife surveillance in detecting ticks. Combined, these data indicate that H. longicornis was present in the USA for years before its detection in New Jersey and was much more widespread than initially believed. Initially, H. longicornis was primarily detected in the mid-Atlantic states, where this tick is now well known to occur; however, our passive surveillance efforts detected H. longicornis as far north as Pennsylvania and as far south as Georgia, and have contributed greatly to the current understanding of this tick’s currently known geographical and host ranges [49]. In total from these data, 11 counties were classified as established for H. longicornis, nine of which represent new counties, including the one for the most southern detections of H. longicornis in the USA—Pickens County, GA [59].

During this study, four Ixodes species were collected from wildlife. As expected, given the hosts sampled, I. scapularis (n = 4,846) was the most abundant and widespread Ixodes species detected. This tick species was not detected in the more western states, but this is likely due to fewer submitted samples from that area and these states being on the edge of currently recognized I. scapularis distribution [57]. From our surveillance, a total of 35 new counties have established I. scapularis populations (ArboNET). These new counties had either been previously classified as reported or had no data. Our passive surveillance using wildlife has provided valuable information for public health officials, as I. scapularis is a vector for numerous important human pathogens such as B. burgdorferi and Babesia microti. Surprisingly, few I. affinis ticks (n = 38) were detected during this study, with positive hosts being white-tailed deer submitted from Florida and North Carolina. Ixodes affinis is widespread in the coastal regions of the southeastern USA and is currently undergoing a northern range expansion [65]. Unlike I. scapularis, I. affinis is found on deer during the summer, so the bias of deer sampling during hunting season likely explains the limited detections. Additionally, I. cookei (n = 201) and I. texanus (n = 15) were also collected, and both are widespread east of the Mississippi River and mainly infest a diversity of small- to medium-sized hosts. Our detection of I. cookei on a red-backed vole represents a new host record for this tick [75]. Finally, 202 Ixodes ticks could not be identified due to damage to key morphological features; these samples represent a limitation to passive surveillance work, as the quality of specimens submitted may not always be ideal. Fortunately, molecular techniques are available to identify these specimens; however, because the overall number of damaged ticks received was low (< 1%), molecular identification was not pursued.

Two species of Amblyomma ticks were collected during this study: A. americanum (n = 10,942) and A. maculatum (n = 848). Amblyomma americanum was the most abundant tick species collected in the study; however, both A. americanum and A. maculatum were widespread in the southern states, with detections becoming more limited further north toward the edge of their currently recognized ranges [65, 74]. Surprisingly, we detected A. maculatum more inland than previously reported; however, with a lack of publicly available county-level data, we are unable to determine whether our surveillance for these species has resulted in any new distribution records. Regardless, 115 and 16 counties were classified as established for A. americanum and A. maculatum, respectively. It is important to note that these two species are important pathogen vectors in the southeastern USA and are more likely to transmit pathogens to domestic animals and humans than I. scapularis due to their aggressive host-seeking behaviors [63, 65]. In addition, A. americanum is most commonly associated with alpha-gal syndrome (red meat allergy) [77].

Finally, two Dermacentor species were also collected during this study: D. variabilis (n = 1,804) was the most abundant, followed by D. albipictus (n = 1,240). Both species of tick were sporadically detected but collected widely across the study region. Submitted samples resulted in 11 and 35 established counties for D. variabilis and D. albipictus, respectively. Dermacentor variabilis is a vector for R. rickettsii, the causative agent of Rocky Mountain spotted fever, and commonly found infesting medium- to large-sized mammals as adults, and smaller mammals during its immature life stages [75]. Black bear was the host most commonly infested with this tick species. Additionally, D. albipictus, known as the winter tick, is commonly associated with cervid species, which is consistent with our detections. Dermacentor albipictus is a serious pest for moose, on which severe infestations can lead to alopecia, emaciation, and potentially death. Interestingly, infestations rarely become as severe on other cervid species; however, recently an elk in Pennsylvania was found dead due to severe D. albipictus infestation [78].

A majority of ticks collected from this study were hard ticks (Ixodidae), but we also detected 26 soft ticks, O. megnini (Argasidae). Soft ticks are rarely found in the environment, as they are mostly nidicolous (nest-dwelling) [79]. Otobious megnini is widely distributed in the southern and western USA; however, sporadic detections have been made in the eastern USA as a result of animal movement [75, 80, 81]. The limited detections in our study were likely because this tick lives in the ear canal of its hosts, and biologist collaborators were only asked to examine the skin of animals for ticks. This tick is currently not known to transmit any pathogens, but it can infest a diversity of wildlife and domestic mammalian hosts [75].

This study provided important new distribution and host data for many tick species, but there are several limitations regarding the utility and interpretation of the data as highlighted in Eisen and Eisen [82]. Our tick collections were opportunistic and based on the ability of our agency partners to collect ticks from the hosts; therefore, we lack accurate data on tick burden on each host. In addition, since a majority of the ticks collected in this study were collected from hosts, the interpretation of precise spatial data (when and if provided) is challenging, especially for hosts that have large home ranges, as we do not know the geographical origin of the tick or the precise location where it interacted with the hosts. Another limitation is that no ticks included in this study were tested for pathogens, because most host-attached ticks could contain host blood which prevents accurate interpretation of pathogen detection data (i.e., was the tick infected or was the host infected). To effectively determine pathogen prevalence and distribution, testing of host-seeking ticks is recommended [58, 82]. Even with these drawbacks, this type of large-scale study and the data it generated provided valuable baseline data for many new hosts and regions for ticks of medical and veterinary concern.

Conclusions

Our study utilizing passive wildlife surveillance for ticks across the eastern USA is an effective method for surveying a diversity of wildlife host species, allowing us to better collect widespread data on current tick distributions relevant to human and animal health. At present, there are several large-scale tick surveillance studies in the USA; however, none focus primarily on wildlife species. This study has collected valuable data regarding the distribution and host associations of exotic H. longicornis; in addition, valuable information about native tick species relevant to human and animal health was also collected.

Availability of data and materials

The datasets used and analyzed during the current study are available from the corresponding author on reasonable request.

References:

  1. Gage KL, Burkot TR, Eisen RJ, Hayes EB. Climate and vectorborne diseases. Am J Prev Med. 2008;35:436–50.

    Article  PubMed  Google Scholar 

  2. Léger E, Vourc’h G, Vial L, Chevillon C, McCoy KD. Changing distributions of ticks: causes and consequences. Exp Appl Acarol. 2013;59:219–44.

    Article  PubMed  Google Scholar 

  3. Showler AT, Pérez de León A. Landscape ecology of Rhipicephalus (Boophilus) microplus (Ixodida: Ixodidae) outbreaks in the south Texas coastal plain wildlife corridor including man-made barriers. Environ Entomol. 2020;49:546–52.

    Article  PubMed  Google Scholar 

  4. Tsao JI, Hamer SA, Han S, Sidge JL, Hickling GJ. The contribution of wildlife hosts to the rise of ticks and tick-borne diseases in North America. J Med Entomol. 2021;2020:1–23.

    Google Scholar 

  5. Williams CF, Britton JR, Turnbull JF. A risk assessment for managing non-native parasites. Biol Invasions. 2013;15:1273–86.

    Article  Google Scholar 

  6. Golnar AJ, Martin E, Wormington JD, Kading RC, Teel PD, Hamer SA, et al. Reviewing the potential vectors and hosts of African swine fever virus transmission in the United States. Vector Borne Zoonotic Dis. 2019;19:512–24.

    Article  PubMed  PubMed Central  Google Scholar 

  7. Pérez de León A, Teel PD, Li A, Ponnusamy L, Roe RM. Advancing integrated tick management to mitigate burden of tick-borne diseases. Outlooks Pest Manag. 2014;25:187.

    Article  Google Scholar 

  8. Jongejan F, De Jong S, Voskuilen T, Van Den Heuvel L, Bouman R, Heesen H, et al. “Tekenscanner”: a novel smartphone application for companion animal owners and veterinarians to engage in tick and tick-borne pathogen surveillance in the Netherlands. Parasites Vectors. 2019;12:116.

    Article  Google Scholar 

  9. Kopsco HL, Xu G, Luo C, Rich SM, Mather TN. Crowdsourced photographs as an effective method for large-scale passive tick surveillance. J Med Entomol. 2020;57:1955–63.

    Article  PubMed  Google Scholar 

  10. Kopsco HL, Duhaime RJ, Mather TN. Crowdsourced tick image-informed updates to U.S. County records of three medically important tick species. J Med Entomol. 2021;58:2421–24.

    Article  PubMed  PubMed Central  Google Scholar 

  11. Cull B. Potential for online crowdsourced biological recording data to complement surveillance for arthropod vectors. PLoS ONE. 2021;16:1–25.

    Article  CAS  Google Scholar 

  12. Tulloch JSP, McGinley L, Sánchez-Vizcaíno F, Medlock JM, Radford AD. The passive surveillance of ticks using companion animal electronic health records. Epidemiol Infect. 2017;145:2020–9.

    Article  CAS  PubMed  Google Scholar 

  13. Saleh MN, Sundstrom KD, Duncan KT, Ientile MM, Jordy J, Ghosh P, et al. Show us your ticks: a survey of ticks infesting dogs and cats across the USA. Parasit Vectors. 2019;12:595.

    Article  Google Scholar 

  14. Nieto NC, Porter WT, Wachara J, Lowrey TJ, Martin L, Motyka PJ, et al. Using citizen science to describe the prevalence and distribution of tick bite and exposure to tick-borne diseases inn the United States. PLoS ONE. 2018;13:e0199644.

    Article  PubMed  PubMed Central  CAS  Google Scholar 

  15. Koffi JK, Leighton PA, Pelcat Y, Trudel L, Lindsay LR, Milord F, et al. Passive surveillance for I. scapularis ticks: enhanced analysis for early detection of emerging lyme disease risk. J Med Entomol. 2012;49:400–9.

    Article  PubMed  Google Scholar 

  16. Ogden NH, Trudel L, Artsob H, Barker IK, Beauchamp G, Charron DF, et al. Ixodes scapularis ticks collected by passive surveillance in Canada: analysis of geographic distribution and infection with lyme borreliosis agent Borrelia burgdorferi. J Med Entomol. 2006;43:600–9.

    Article  CAS  PubMed  Google Scholar 

  17. Porter WT, Motyka PJ, Wachara J, Barrand ZA, Hmood Z, McLaughlin M, et al. Citizen science informs human-tick exposure in the northeastern United States. Int J Health Geogr. 2019;18:1–14.

    Article  Google Scholar 

  18. Trout Fryxell RT, Vogt JT. Collaborative-tick surveillance works: an academic and government partnership for tick surveillance in the southeastern United States (Acari: Ixodidae). J Med Entomol. 2019;56:1411–9.

    Article  CAS  PubMed  Google Scholar 

  19. Lee X, Murphy DS, Johnson DH, Paskewitz SM. Passive animal surveillance to identify ticks in Wisconsin, 2011–2017. Insects. 2019;10:18–29.

    Article  Google Scholar 

  20. Rand PW, Lacombe EH, Dearborn R, Cahill B, Elias S, Lubelczyk CB, et al. Passive surveillance in Maine, an area emergent for tick-borne diseases. J Med Entomol. 2007;44:1118–29.

    Article  PubMed  Google Scholar 

  21. Pak D, Jacobs SB, Sakamoto JM. A 117-year retrospective analysis of Pennsylvania tick community dynamics. Parasit Vectors. 2019;12:189.

    Article  Google Scholar 

  22. Lockwood BH, Stasiak I, Pfaff MA, Cleveland CA, Yabsley MJ. Widespread distribution of ticks and selected tick-borne pathogens in Kentucky (USA). Ticks Tick Borne Dis. 2018;9:738–41.

    Article  PubMed  Google Scholar 

  23. Chenery ES, Henaff M, Magnusson K, Harms NJ, Mandrak NE, Moln K. Improving widescale monitoring of ectoparasite presence in northern Canadian wildlife with the aid of citizen science. Insects. 2022;23:380.

    Article  PubMed  PubMed Central  Google Scholar 

  24. Rainey T, Occi JL, Robbins RG, Egizi A. Discovery of Haemaphysalis longicornis (Ixodida: Ixodidae) parasitizing a sheep in New Jersey, United States. J Med Entomol. 2018;55:757–9.

    Article  PubMed  Google Scholar 

  25. Heath ACG. Biology, ecology and distribution of the tick, Haemaphysalis longicornis Neumann (Acari: Ixodidae) in New Zealand. N Z Vet J. 2016;64:10–20.

    Article  PubMed  Google Scholar 

  26. Hoogstraal H, Roberts FHS, Kohls TGM, Tipton VJ. Review of Haemaphysalis (Kaiseriana) longicornis Neumann (Resurrected) of Australia, New Zealand, New Caledonia, Fiji, Japan, Korea, and northeastern China and USSR, and its parthenogenetic and bisexual populations (Ixodoidea, Ixodidae). J Parasitol. 1968;54:1197–213.

    Article  CAS  PubMed  Google Scholar 

  27. Ben Beard C, Occi J, Bonilla DL, Egizi AM, Fonseca DM, Mertins JW, et al. Multistate Infestation with the Exotic Disease–Vector Tick Haemaphysalis longicornis—United States, August 2017–September 2018. Morbitity Mortal Wkly Rep. 2018;67:1310–3.

    Article  Google Scholar 

  28. Chen Z, Yang X, Bu F, Yang X, Yang X, Liu J. Ticks (Acari: Ixodoidea: Argasidae, Ixodidae) of China. Exp Appl Acarol. 2010;51:393–404.

    Article  PubMed  Google Scholar 

  29. Breuner NE, Ford SL, Hojgaard A, Osikowicz LM, Parise CM, Rosales Rizzo MF, et al. Failure of the Asian longhorned tick, Haemaphysalis longicornis, to serve as an experimental vector of the lyme disease spirochete, Borrelia burgdorferi sensu stricto. Ticks Tick Borne Dis. 2019;11:101311.

    Article  PubMed  PubMed Central  Google Scholar 

  30. Stanley HM, Ford SL, Snellgrove AN, Hartzer K, Smith EB, Krapiunaya I, et al. The ability of the anvasive Asian longhorned tick, Haemaphysalis longicornis (Acari: Ixodidae), to acquire and transmit Rickettsia rickettsii (Rickettsiales: Rickettsiaceae), the agent of rocky mountain spotted fever, under laboratory conditions. J Med Entomol. 2020;57:1635–39.

    Article  PubMed  Google Scholar 

  31. Levin ML, Stanley HM, Hartzer K, Snellgrove AN. Incompetence of the Asian longhorned tick (Acari: Ixodidae) in transmitting the agent of human granulocytic anaplasmosis in the United States. J Med Entomol. 2021;58:1419–23.

    Article  CAS  PubMed  Google Scholar 

  32. Raney WR, Perry JB, Hermance ME. Transovarial transmission of heartland virus by invasive Asian longhorned ticks under laboratory conditions. Emerg Infect Dis. 2022;28:3–6.

    Article  Google Scholar 

  33. Price K, Graham C, Witmier B, Chapman H, Coder B, Boyer C, et al. Borrelia burgdorferi sensu stricto DNA in field-collected Haemaphysalis longicornis ticks, Pennsylvania, United States. Emerg Infect Dis J. 2021;27:608.

    Article  CAS  Google Scholar 

  34. Price K, Ayres BN, Maes SE, Witmier BJ, Chapman HA, Coder BL, et al. First detection of human pathogenic variant of Anaplasma phagocytophilum in field-collected Haemaphysalis longicornis, Pennsylvania, USA. Zoonoses Public Health. 2022;69:143–8.

    Article  PubMed  Google Scholar 

  35. Thompson AT, White SA, Shaw D, Garrett KB, Wyckoff ST, Doub EE, et al. A multi-seasonal study investigating the phenology, host and habitat associations, and pathogens of Haemaphysalis longicornis in Virginia, U.S.A. Ticks Tick Borne Dis. 2021;12:101773.

    Article  PubMed  Google Scholar 

  36. Cumbie A, Trimble R, Eastwood G. Pathogen spillover to an invasive tick species : first detection of Bourbon virus in Haemaphysalis longicornis in the United States. Pathogens. 2022;11:454.

    Article  PubMed  PubMed Central  Google Scholar 

  37. Oakes VJ, Yabsley MJ, Schwartz D, Leroith T, Bissett C, Broaddus C, et al. Theileria orientalis Ikeda genotype in cattle, Virginia, USA. Emerg Infect Dis. 2019;25:1653–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Dinkel KD, Herndon DR, Noh SM, Lahmers KK, Todd SM, Ueti MW, et al. A.U.S. isolate of Theileria orientalis, Ikeda genotype, is transmitted to cattle by the invasive Asian longhorned tick, Haemaphysalis longicornis. Parasites Vectors. 2021;14:157.

    Article  CAS  Google Scholar 

  39. Thompson AT, White S, Shaw D, Egizi AM, Lahmers KK, Ruder MG, et al. Theileria orientalis Ikeda in host-seeking Haemaphysalis longicornis in Virginia, U.S.A. Ticks Tick Borne Dis. 2020;11:101450.

    Article  PubMed  Google Scholar 

  40. Tufts DM, VanAcker MC, Fernandez MP, Denicola A, Egizi A, Diuk-Wasser MA. Distribution, host-seeking phenology, and host and habitat associations of Haemaphysalis longicornis ticks, Staten Island, New York, USA. Emerg Infect Dis. 2019;25:792–6.

    Article  PubMed  PubMed Central  Google Scholar 

  41. White SA, Bevins SN, Ruder MG, Shaw D, Vigil SL, Randall A, et al. Surveys for ticks on wildlife hosts and in the environment at Asian longhorned tick (Haemaphysalis longicornis)-positive sites in Virginia and New Jersey. Transbound Emerg Dis. 2018;2020:1–10.

    Google Scholar 

  42. NCDA&CS. State Veterinarian reminds livestock and pet owners to watch out for ticks: Recent cattle deaths in Surry County linked to Asian longhorned ticks. 2019. https://www.ncagr.gov/paffairs/release/2019/StateVeterinarianremindslivestockandpetownerstowatchoutforticks.htm. Accessed 8 May 2022.

  43. Egizi AM, Occi JL, Price DC, Fonseca DM. Leveraging the expertise of the New Jersey mosquito control community to jump start standardized tick surveillance. Insects. 2019;10:219.

    Article  PubMed Central  Google Scholar 

  44. Trout Fryxell RT, Vann DN, Butler RA, Paulsen DJ, Chandler JG, Willis MP, et al. Rapid discovery and detection of Haemaphysalis longicornis through the use of passive surveillance and collaboration: Building a state tick-surveillance network. Int J Environ Res Public Health. 2021;18:7980.

    Article  PubMed  PubMed Central  Google Scholar 

  45. Tufts DM, Goodman LB, Benedict MC, Davis AD, VanAcker MC, Diuk-Wasser M. Association of the invasive Haemaphysalis longicornis tick with vertebrate hosts, other native tick vectors, and tick-borne pathogens in New York City, USA. Int J Parasitol. 2021;51:149–57.

    Article  CAS  PubMed  Google Scholar 

  46. Magori K. Preliminary prediction of the potential distribution and consequences of Haemaphysalis longicornis using a simple rule-based climate envelope model. bioRxiv. 2018;10:389940.

    Google Scholar 

  47. Raghavan RK, Barker SC, Cobos ME, Barker D, Teo EJM, Foley DH, et al. Potential spatial distribution of the newly introduced long-horned tick, Haemaphysalis longicornis in North America. Sci Rep. 2019;9:498.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  48. Namgyal J, Couloigner I, Lysyk TJ, Dergouso SJ, Cork SC. Comparison of habitat suitability models for Haemaphysalis longicornis Neumann in North America to determine its potential geographic range. Int J Environ Res Public Health. 2020;17:8285.

    Article  PubMed Central  Google Scholar 

  49. USDA-APHIS. National Haemaphysalis longicornis (Asian longhorned tick) Situation report. 2022. https://www.aphis.usda.gov/animal_health/animal_diseases/tick/downloads/longhorned-tick-sitrep.pdf. Accessed 8 May 2022.

  50. Egizi AM, Robbins RG, Beati L, Nava S, Evans CR, Occi JL, et al. A pictorial key to differentiate the recently detected exotic Haemaphysalis longicornis Neumann, 1901 (Acari, Ixodidae) from native congeners in North America. Zookeys. 2019;818:117–28.

    Article  Google Scholar 

  51. Thompson AT, Dominguez K, Cleveland CA, Dergousoff SJ, Doi K, Falco RC, et al. molecular characterization of Haemaphysalis species and a molecular genetic key for the identification of Haemaphysalis of North America. Front Vet Sci. 2020;7:1–11.

    Article  CAS  Google Scholar 

  52. Walker A. The genus Rhipicephalus (Acari, Ixodidae): a guide to the brown ticks of the world. Trop Anim Heal Prod. 2000;32:417–8.

    Article  Google Scholar 

  53. Keirans JE, Litwak TR. Pictorial key to the adults of hard ticks, family Ixodidae (Ixodida: Ixodoidea), east of the Mississippi river. J Med Entomol. 1989;26:435–48.

    Article  CAS  PubMed  Google Scholar 

  54. Cooley R, Kohls GM. The genus Amblyomma (Ixodidae) in the United States. J Parasitol. 1944;30:77–111.

    Article  Google Scholar 

  55. Durden LA, Keirans JE. Nymphs of the genus Ixodes (Acari: Ixodidae) of the United States: Taxonomy, identification key, distribution, hosts, and medical/veterinary importance. Annapolis: Entomological Society of America; 1996.

    Google Scholar 

  56. Clifford CM, Anastos G, Elbl A. The larval Ixodid ticks of the eastern United States (Acarina-Ixodidae). College Park: Entomological Society of America; 1961. p. 215–37.

    Google Scholar 

  57. Eisen RJ, Eisen L, Beard CB. County-Scale distribution of Ixodes scapularis and Ixodes pacificus (Acari: Ixodidae) in the continental United States. J Med Entomol. 2016;53:349–86.

    Article  PubMed  Google Scholar 

  58. CDC-NCEZID. Surveillance for Ixodes scapularis and pathogens found in this tick species in the United States. 2019. https://www.cdc.gov/ticks/resources/TickSurveillance_Ipacificus-P.pdf. Accessed 8 May 2022.

  59. Molaei G, Little EAH, Williams SC, Stafford KC. First record of established populations of the invasive pathogen vector and ectoparasite Haemaphysalis longicornis (Acari: Ixodidae) in Connecticut, United States. J Med Entomol. 2021;58:2508–13.

    Article  PubMed  Google Scholar 

  60. Springer YP, Eisen L, Beati L, James AM, Eisen RJ. Spatial distribution of counties in the continental United States with records of occurrence of Amblyomma americanum (Ixodida: Ixodidae). J Med Entomol. 2014;51:342–51.

    Article  PubMed  Google Scholar 

  61. Molaei G, Little EAH, Khalil N, Ayres BN, Nicholson WL, Paddock CD. Established population of the Gulf Coast tick, Amblyomma maculatum (Acari: Ixodidae), infected with Rickettsia parkeri (Rickettsiales: Rickettsiaceae), in Connecticut. J Med Entomol. 2021;58:1459–62.

    Article  PubMed  Google Scholar 

  62. Brinkerhoff RJ, Folsom-O’Keefe CM, Tsao K, Diuk-Wasser MA. Do birds affect Lyme disease risk? Range expansion of the vector-borne pathogen Borrelia burgdorferi. Front Ecol Environ. 2011;9:103–10.

    Article  Google Scholar 

  63. Childs JE, Paddock CD. The ascendancy of Amblyomma americanum as a vector of pathogens affecting humans in the United States. Annu Rev Entomol. 2003;48:307–37.

    Article  CAS  PubMed  Google Scholar 

  64. Dergousoff SJ, Galloway TD, Lindsay LR, Curry PS, Chilton NB. Range expansion of Dermacentor variabilis and Dermacentor andersoni (Acari: Ixodidae) near their northern distributional limits. J Med Entomol. 2013;50:510–20.

    Article  PubMed  Google Scholar 

  65. Nadolny RM, Gaff HD. Natural history of Amblyomma maculatum in Virginia. Ticks Tick Borne Dis. 2018;9:188–95.

    Article  PubMed  Google Scholar 

  66. Florin DA, Jory Brinkerhoff R, Gaff H, Jiang J, Robbins RG, Eickmeyer W, et al. Additional U.S. collections of the Gulf Coast tick, Amblyomma maculatum (Acari: Ixodidae), from the state of Delaware, the first reported field collections of adult specimens from the state of Maryland, and data regarding this tick from surveillance of migratory songbirds of Maryland. Syst Appl Acarol. 2014;19:257–62.

    Google Scholar 

  67. Egizi A, Erika LB, Waheed A, Bernick J, Bickerton M, Campbell SR, et al. First glimpse into the origin and spread of the Asian longhorned tick, Haemaphysalis longicornis, in the United States. Zoonoses Public Health. 2020;67:637–50.

    Article  PubMed  Google Scholar 

  68. Heath ACG. A history of the introduction, establishment, dispersal and management of Haemaphysalis longicornis Neumann, 1901 (Ixodida: Ixodidae) in New Zealand. New Zeal J Zool. 2000;47:241–7.

    Article  Google Scholar 

  69. Koser TM. Comparison of different surveillance methods for modeling dispersal of ticks. University of Georgia; 2019. http://getd.libs.uga.edu/pdfs/koser_troy_m_201905_ms.pdf. Accessed 8 May 2022.

  70. Dennis DT, Nekomoto TS, Victor JC, Paul WS, Piesman J. Reported distribution of Ixodes scapularis and Ixodes pacificus (Acari: Ixodidae) in the United States. J Med Entomol. 1998;35:629–38.

    Article  CAS  PubMed  Google Scholar 

  71. Cohen SB, Freye JD, Dunlap BG, Dunn JR, Jones TF, Moncayo AC. Host associations of Dermacentor, Amblyomma, and Ixodes (Acari: Ixodidae) ticks in Tennessee. J Med Entomol. 2010;47:415–20.

    CAS  PubMed  Google Scholar 

  72. Kollars TM, Oliver JH, Durden LA, Kollars PG. Host associations and seasonal activity of Amblyomma americanum (Acari: Ixodidae) in Missouri. J Parasitol. 2000;86:1156–9.

    Article  PubMed  Google Scholar 

  73. Schulze TL, Jordan RA, Schulze CJ. Host associations of Ixodes scapularis (Acari: Ixodidae) in residential and natural settings in a Lyme disease-endemic area in New Jersey. J Med Entomol. 2005;42:966–73.

    Article  PubMed  Google Scholar 

  74. CDC-NCEZID. Guide to the surveillance of metastriate ticks (Acari : Ixodidae) and their pathogens in the United States. 2020. https://www.cdc.gov/ticks/pdfs/Tick_surveillance-P.pdf. Accessed 8 May 2022.

  75. Allan SA. Ticks (Class Arachnida: Order Acarina). Parasitic diseases of wild mammals. Ames: Iowa State University Press; 2001. p. 72–106.

  76. Rosenberg R, Lindsey NP, Fischer M, Gregory CJ, Hinckley AF, Mead PS, et al. Vital signs: trends in reported vectorborne disease cases—United States and Territories, 2004–2016. Morb Mortal Wkly Rep. 2018;67:496–501.

    Article  Google Scholar 

  77. Mitchell CL, Lin FC, Vaughn M, Apperson CS, Meshnick SR, Commins SP. Association between lone star tick bites and increased alpha-gal sensitization: evidence from a prospective cohort of outdoor workers. Parasit Vectors. 2020;13:1–4.

    Article  CAS  Google Scholar 

  78. Calvente E, Chinnici N, Brown J, Banfield JE, Brooks JW, Yabsley MJ. Winter tick (Dermacentor albipictus)–associated dermatitis in a wild elk (Cervus canadensis) in Pennsylvania, USA. J Wildl Dis. 2020;56:247–50.

    Article  CAS  PubMed  Google Scholar 

  79. Vial L. Biological and ecological characteristics of soft ticks (Ixodida: Argasidae) and their impact for predicting tick and associated disease distribution. Parasite. 2009;16:191–202.

    Article  CAS  PubMed  Google Scholar 

  80. Keirans JE, Pound JM. An annotated bibliography of the spinose ear tick, Otobius megnini (Dugès, 1883) (Acari: Ixodida: Argasidae) 1883–2000. Syst Acarol Acarol Spec Publ. 2003;13:1–68.

    Google Scholar 

  81. Cooley RA. The Argasidae of North America, Central America and Cuba. Notre Dame, Ind.: The University Press,; 1944. Science. 1945. https://doi.org/10.1126/science.101.2631.56.

    Article  Google Scholar 

  82. Eisen L, Eisen RJ. Benefits and drawbacks of citizen science to complement traditional data gathering approaches for medically important hard ticks (Acari: Ixodidae) in the United States. J Med Entomol. 2021;58:1-9.

    Article  PubMed  Google Scholar 

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Acknowledgements

We thank numerous biologists and veterinarians in SCWDS member state agencies for sample collection and submission as well as the biologists at NVSL for morphology confirmation for H. longicornis suspects.

Funding

This study was made possible by the continued financial support from SCWDS member state wildlife agencies provided by the Federal Aid to Wildlife Restoration Act (50 Stat. 917). Partial funding was provided through Cooperative Agreements AP19VSCEAH00C004 and AP20VSCEAH00C041, Veterinary Services, Animal and Plant Health Inspection Service, USDA. Additional support was provided by SCWDS federal agency partners, including the United States Geological Survey Ecosystems Mission Area and the United States Fish and Wildlife Service National Wildlife Refuge System. ATT was partially supported by the National Science Foundation under DGE-1545433 (UGA’s Interdisciplinary Disease Ecology Across Scales program) and through the USDA Animal Plant Health Inspection Service’s National Bio- and Agro-defense Facility Scientist Training Program AP20VSD&B000C085. KD was supported by the National Institute of General Medical Sciences of the National Institutes of Health under R25GM109435 (UGA’s Post-Baccalaureate Research Education Program). The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH, NSF, or USDA.

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Author notes

  1. Alec T. Thompson and Seth A. White contributed equally to this study

Authors and Affiliations

  1. Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA, USA

    Alec T. Thompson, Seth A. White, Emily E. Doub, Prisha Sharma, Kenna Frierson, Kristen Dominguez, David Shaw, Stacey L. Vigil, Mark G. Ruder & Michael J. Yabsley

  2. Center for the Ecology of Infectious Diseases, Odum School of Ecology, University of Georgia, Athens, GA, USA

    Alec T. Thompson & Michael J. Yabsley

  3. Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA, USA

    Seth A. White, Kenna Frierson & Michael J. Yabsley

  4. Department of Environmental Health Sciences, College of Public Health, University of Georgia, Athens, GA, USA

    Prisha Sharma

  5. Georgia Department of Agriculture, Atlanta, GA, USA

    Dustin Weaver

  6. United States Department of Agriculture, Veterinary Services, Fort Collins, CO, USA

    Denise L. Bonilla

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Contributions

AT, ED, DS, MR, MY, SV, and SW participated in study design and contacted agency partners. AT, SV, and MY drafted manuscript. AT analyzed and visualized all data. All authors read and approved the final manuscript.

Corresponding authors

Correspondence to Alec T. Thompson or Michael J. Yabsley.

Ethics declarations

Ethics approval and consent to participate

Tick specimens collected from hosts included in this study were collected under AUPs: A2010 09–179; A2010 10–186; A2013 01–005; A2013 07–003; A2014 10–018; A2018 02–010 A2020 11–010; A2021 08–007.

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Supplementary Information

Additional file 1:

Summary of tick submissions from hosts and from different states during surveillance efforts, 2010–2021. Excel file containing summary data of total number of tick submissions for state and host. Details number of state submissions, number of hosts sampled per state, number of ticks submitted (by host species), percent of host species infested with tick species along with mean and range of ticks collected from hosts, and total counts of tick life stages by host.

Additional file 2:

Number of host submissions by state. Graphic detailing number of hosts submitted by state.

Additional file 3:

Established tick populations. Excel file containing summary data of different tick species meeting the “established” county criteria. Contains tick and host species, state and county name, date of collection, and what establishment criteria was met (> 6 individuals or > 1 life stage).

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Thompson, A.T., White, S.A., Doub, E.E. et al. The wild life of ticks: Using passive surveillance to determine the distribution and wildlife host range of ticks and the exotic Haemaphysalis longicornis, 2010–2021. Parasites Vectors 15, 331 (2022). https://doi.org/10.1186/s13071-022-05425-1

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Parasites & Vectors

ISSN: 1756-3305

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