INVESTIGATING THE ECOLOGY OF IXODES SCAPULARIS, THE VECTOR OF THE AGENT OF LYME DISEASE AND OTHER TICK-BORNE PATHOGENS TO BETTER PREDICT AND REDUCE FUTURE RISK OF TICK-BORNE DISEASES

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: COMPLETE
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1008671
• Project Start Date: Feb 1, 2016
• Project End Date: Jan 31, 2021
• Program Code: [(N/A)]- (N/A)

Project Director
Tsao, J.

Recipient Organization
MICHIGAN STATE UNIV
(N/A)
EAST LANSING,MI 48824

Performing Department
Fisheries & Wildlife

Non Technical Summary
Emerging infectious diseases and their vectors cause considerable damage to human, domestic animal and wildlife health, which can have negative impacts on ecosystem health and socio-economic systems. The global rate of increase in emerging infectious diseases of humans, wildlife, and livestock in the last half century has been due in large part to anthropogenic factors associated with increased globalization, landscape/land use changes, and climate change (Jones et al. 2008, Dobson and Foupopolos 2001).In the last half century, North America has experienced several emerging vector-borne pathogens, pathogens that are transmitted amongst hosts by arthropods, including mosquitoes, flies, and ticks. West Nile virus (WNv), vectored by mosquitoes emerged in New York City in 1999; within five years, it spread to the other coast. WNv causes death among humans, horses and many wild avian species. With both native mosquito species already in place as well as invasive non-native species spreading, public health officials are preparing for the introduction of other pathogens, including dengue and chikungunya viruses that are at our southern doorsteps. There also have been tick species that have been progressively increasing in local abundance and expanding their ranges at a continental level. The most well-known in the north is the Lyme disease vector, the blacklegged (=deer) tick, Ixodes scapularis. In the south, Amblyomma americanum, the lone star tick, similarly has been aggressively increasing its reach northwards. The lone star tick is a pest of livestock and captive cervids and vectors at least one rickettsial pathogen and one virus to humans. Amblyomma maculatum is another tick that vectors rickettsiae that has been spreading north from its originally limited distribution in the Gulf coast states, for which it is named. With regard to wildlife, epizootic hemorrhagic disease virus (EHDv), vectored by a midge, has been striking white-tailed deer populations with increased frequency in northern states. The increase in EHDv in deer is a harbinger for possible increased disease in sheep and cows, as EHDv is very closely related to blue-tongue virus, which is also spread by midges and has a similar ecology. Furthermore, in the last two decades, blue tongue has been emerging northwards in Europe. The problem: What are the ultimate and proximate factors resulting in the emergence of infectious diseases, and particularly, of vector-borne pathogens? Furthermore, how can the spread, risk, and negative impacts be limited?Proposed research in my lab to address this problem: My lab focuses on investigating the ecology of Lyme disease, and in particular, its emergence. By investigating processes leading to emergence, we can work to develop innovative approaches to improve detection as well as management activities to aid in control and reduction in public health risk. My lab also has been conducting comparative ecological studies of the Lyme disease tick in different regions of its range in order to understand how the disease risk may change in the future as climate changes. Research in the Lyme disease system serves as a model for understanding the factors responsible for the emergence of tick-borne, vector-borne, and zoonotic pathogens, and of invasive species in general.Because the emergence of Lyme disease is linked to anthropogenic changes involving changes in natural resource, landscape and land use, and climate change, our research falls within MAES' mission, to engage in innovative, leading-edge research that combines scientific expertise with practical experience to generate economic prosperity, sustain natural resources and enhance the quality of life in Michigan, the nation and the world. Most directly, my lab addresses the specific knowledge area of zoonotic diseases and parasites affecting humans (722). Indirectly, or as a consequence, research in my lab also addresses the specific knowledge areas 1) aquatic and terrestrial wildlife (135), weather and climate (132), as well as conservation of biological diversity (136). The work in my lab is of significance to Michigan because the blacklegged tick, the vector of the agent of Lyme disease, to humans and domestic animals has been emerging across the state, having an impact on public health and companion animal health. The Michigan Department of Health and Human Services does not a budget to conduct surveillance or ecological studies to monitor and predict the spread of the tick and associated tick-borne diseases, and thus the work conducted in my lab has direct benefit to MDHHS and the citizens of Michigan. Furthermore, in the course of our ecological studies, we also may detect the invasion of the lone star tick, which has been detected with increased frequency in adjacent states. As Michigan is just one of many states undergoing invasion of the blacklegged tick, our results and research approaches may be helpful not just to Michigan but states in the northern central U.S. region. Furthermore, because we are working in multiple regions in the eastern to understand how Lyme disease risk will change under non-stationary conditions such as climate change, the work we do in my lab has implications at the national and North American level. Because Lyme disease is a global disease and because the ecology of their Lyme disease tick vector varies across Eurasian countries in a similar fashion, findings in my lab have global implications.Lyme disease is the most frequently reported vector-borne disease in Europe, western Asia, and is now emerging in eastern Asia as well. As in the U.S., a combination anthropogenic factors most likely have caused the emergence or resurgence in Lyme disease and associated tick-borne diseases in other countries. The management of wildlife, forests, and land use and a changing climate all affect disease risk. As arthropod life cycles, and therefore pathogen transmission cycles, are highly dependent on abiotic factors, it is very important to study how climate change will impact the maintenance and spread of vector-borne diseases. The intersections of the management of wildlife, improving public health, and environmental stewardship, not only happen to fall within MAES mission and a specific target area, but also form the raison d'être of MSU's Conservation Medicine program, a joint initiative of the College of Agriculture and Natural Resources and the College of Veterinary Medicine. Lyme disease emergence provides a model system for the research and management of other tick-borne diseases, vector-borne diseases, and invasive species to improve human, animal, and ecosystem health. Thus, as the Lyme disease system is spreading across the state, it is critical and advantageous to research how the system is spreading in order to try to predict future spread and reduce risk of disease proactively and prospectively.

Animal Health Component

40%

Research Effort Categories

Basic

40%

Applied

40%

Developmental

20%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
722	3120	1070	100%

Knowledge Area
722 - Zoonotic Diseases and Parasites Affecting Humans;

Subject Of Investigation
3120 - Spiders, mites, ticks, and other arthropods;

Field Of Science
1070 - Ecology;

Keywords

disease emergence

vector-borne disease

ticks

lyme disease

climate change

Goals / Objectives
A. Lyme disease emergence: surveillancei) to continue to monitor the invasion of Lyme disease in Michigan by sampling field sites using traditional ecological methodsii) to monitor the invasion of Lyme disease through active surveillance of ticks on canine companion animals.B. Ecology of Lyme disease and other pathogens associated with the blacklegged tick i) to compare the ecology of blacklegged ticks and the Lyme disease pathogen, Borrelia burgdorferi, in northern and southern regions of the US.ii) to investigate the phenotypic differences in traits among blacklegged ticks derived from different areas throughout its rangeiii) to investigate the ecology of Borrelia miyamotoi, another emerging pathogen transmitted by the blacklegged tick.

Project Methods
A. Lyme disease emergence: surveillanceAim i) to continue to monitor the invasion of Lyme disease in Michigan by sampling field sites using traditional ecological methods (e.g., wildlife trapping and dragging for host-seeking ticks)Site selection and sampling regime. We will continue to sample the original sites in Hamer et al. 2010 to monitor for growth of the blacklegged tick and pathogen populations. Based on habitat suitability models (Guerra et al. 2002; Foster et al. 2004), we will survey sites throughout the Lower Peninsula, both where ticks are known to exist as well as where they have not yet been detected. When possible, we will trap mammals, as they are a more sensitive indicator for the presence of ticks than dragging for host-seeking ticks (Hamer et al. 2010), but we mainly will sample for host-seeking ticks because of limited resources but also because they represent more directly the epidemiological risk of disease for humans. Sampling mainly will be conducted early summer, when I.scapularis larvae, nymphs, and adults are simultaneously active, but some late summer sampling when mainly larvae are active will also be conducted. Fall and spring sampling to target questing adults will occur if needed.See Hamer et al. (2010) for methods for mammal trapping, questing tick sampling, and Borrelia burgdorferi detection and sequencing from ticks and ear biopsies. Wildlife procedures have been approved through Michigan State University's Institutional Animal Use and Care Committee permit #02-07-13-000 and are renewed when appropriate.Data analysis. Logistic regression is used to assess trends in wildlife infestation and tick infection over the sampling period. Fishers exact test is used to assess differences in infestation among sites. Linear regression is used to assess trends in nymphal densities within sites over time. Within-year comparisons between the coastal and inland transects are made by calculating the z-ratio and associated two-tail probabilities for the difference between two independent proportions.Aim ii) To monitor the invasion of Lyme disease through active surveillance of ticks on canine companion animals.Veterinary and Shelter Network. This project expands upon a veterinary network constructed by Hamer et al. 2009, in which 18 veterinary clinics in southwestern Michigan provided blood samples and ticks removed from dogs for analysis at Michigan State University. That study was conducted on a regional scale, focused on documenting the invasion of Ixodes scapularis and Borrelia burgdorferi in southwestern Michigan.We propose to create a new veterinary network that spans both the Lower and Upper Peninsulas of Michigan, as the tick is spreading in both. The CAPC website provides the prevalence of seropositive dogs for B. burgdorferi in Michigan from 2011-2014. The overall mean seroprevalence over the last five years is 1.16% (n=310,953), having increased annually from 0.69% (2011, n=46,120) to 1.4% (2014, n=132,931). Given that any dog seropositive for B. burgdorferi must have been exposed via the bite of an infected Ixodes spp. tick (which most likely in this region is I. scapularis), we can use the seroprevalence data to generate a conservative estimate of the prevalence of canine tick infestation. Because only ~40-50% of adult female blacklegged ticks in western Michigan are infected with B. burgdorferi (Hamer et al., 2010), it is likely that dogs are regularly exposed to I. scapularis ticks without becoming infected with B. burgdorferi. Consequently, assuming (based on seropositivity) that only 1% of dogs are likely to be infested with ticks probably underestimates true tick infestation prevalence substantially. Therefore, assuming a large population size of dogs and that veterinarians will detect ticks that are present on a dog they examine 50% of the time (again, likely a conservative assumption), we can be 95% confident of detecting one dog infested with a blacklegged tick, if we sampled at least 600 dogs throughout Michigan.Ten geographically-representative clinics will be selected within each peninsula. From each clinic, we will sample 60 dogs. Because dogs that visit veterinary clinics are generally well cared for, travel with their human companions, and may be on tick prophylaxis, to better estimate the local exposure of itinerant dogs to ticks, we will also recruit the same number of animal shelters throughout the state of Michigan, corresponding to the same counties/area as the recruited veterinary clinic. Thus, our surveillance network will comprise 20 veterinary clinics and 20 animal shelters throughout the state of Michigan.Lists of veterinary clinics and animal shelters within the state will be obtained from their respective state licensing boards. A minimum of 60 dogs will be examined for ticks at each clinic/shelter over a period of 30 days during the spring and late fall (peak adult questing tick periods in Michigan), and all ticks found will be pooled in a single vial for each individual animal. Information obtained for each tick examination will include signalment, the general location of the dog's residence, history of travel, outdoor exposure, and recent chemoprophylaxis use. Tick samples will be stored initially at the veterinary clinic or shelter and later posted to Michigan State University. Thus, overall, there will be [(20 clinics x 60 dogs/clinic) + (20 shelters x 60 dogs/shelter)] per season x 2 seasons = 4,800 dogs examined.Data Analysis. Exploratory data analyses will be carried out via Mantel-Haenszel chi-square analysis to investigate evidence for associations between tick positivity and potential predictors and confounders such as sex, breed, region, clinic/shelter, and use of chemoprophylaxis. Because variables such as geographic region and clinic/veterinarian are likely to impose a correlation structure on the data, generalized linear mixed models (GLMM) will be applied to describe that structure and to control for its effect on the assumption of independence of observations (Kleinbaum 2000).B. Ecology of Lyme disease and other pathogens associated with the blacklegged tick Aim i) to compare the ecology of blacklegged ticks and the Lyme disease pathogen, Borrelia burgdorferi, in northern and southern regions of the US. Borrelia burgdorferi detection: See Hamer et al. 2010 for methods used for pathogen detection in questing and on-host ticks and host biopsy samples.Analysis. The dynamics of the LD cycles at each of the field sites will be further analyzed by integrating the biodiversity and phenology data with an existing modeling structure.Aim ii) to investigate the phenotypic differences in traits among blacklegged ticks derived from different areas throughout its range.General Methods. Below methods are described for analysis, since experiments are completed.Analysis. Generalized Linear Mixed Models (GLMMs) will be used to determine the log-odds of observing the response variable (e.g. questing of nymphs, oviposition, larval emergence from egg hatch, nymphal emergence from larval engorgement, adult emergence from nymphal engorgement, survivorship of each life stage), as a function of geographic origin of ticks and other covariates (e.g., temperature, relative humidity, and photoperiod), depending on the response variable.General methods. Field samples (i.e., questing larvae, nymphs and adults; engorging larvae and nymphs on rodent hosts; engorging adults on deer; rodent biopsies; blood from rodents from one field site) already have been obtained from multiple field sites as part of the Lyme Gradient project.Borrelia miyamotoi detection: See Hamer et al. 2010 for methods used for pathogen detection in questing and on-host ticks and host biopsy samples.

Progress 02/01/16 to 01/31/21

Outputs
Target Audience: The general target audience for my research efforts are research scientists, the public at large, professionals in health care, organizations and agencies with influence on the public health of citizens. Examples of organizations include: Michigan Lyme Disease Association Michigan Department of Community Health Michigan Department of Natural Resources Centers for Disease Control and Prevention Changes/Problems:As mentioned in a previous section, actions to mitigate COVID-19 transmission essentially halted all lab work starting mid-March. My lab was able to conduct field surveillance during the summer in a more limited fashion. We only have recently returned to the lab(early October). What opportunities for training and professional development has the project provided?Graduate students have been encouraged to present their research at local meetings. See "products" section. Graduate students also have had the opportunity to mentor undergraduate students in research. How have the results been disseminated to communities of interest? Graduate students and Principle Investigator Tsaohave presented results at scientific meetings(see "Products" section) and stakeholder conferences. In particular one graduate student (Porter) and I spoke at the Michigan Lyme Disease Assocation Conference, and one graduate student (Kobbedakuwa) spoke at the Michigan Mosquito Control Association conference.These results also have been disseminated at anoutreach event (oral presentation and outreach booth)for outdoors enthusiasts. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Major goals of the project - what was accomlished under these goals? A. Lyme disease emergence: surveillance i) Active surveillance for blacklegged ticks in Michigan via sampling for questing blacklegged ticks in the landscape. In Summer2019 (during the last reporting period), my lab was funded by the CDC toactive surveillance for blacklegged ticks at thestate level. Intotal, we sampled > 495 km from 75 sites spread among 64/83 counties. Subsequent to that, during this curren reporting period, my students extracted the DNA from >2000 of these ticks in order to send to the CDC, who would screening the samples forpathogens. After the CDC would identify ticks infected with the Lyme bacterium (Borrelia burgdorferi) and theagent of human anaplasmosis (Anaplasma phagocytophilum), my lab planneed to further genetically analysein order to better understand the eco-epidemiology and health risk of these pathogens. We sent DNA from more than half the specimens to the CDC in February. Because of COVID-19, the CDC halted or severely reduced pathogen assays and we have not received the results of the initial screening of the first ticks. Similarly, mylab stopped alllaboratory work in mid-March, and thus we did not finish the DNA extractions, and obviously we have not genetically analysed pathogen infections. We have just begun to get back into the lab (Oct 2020). Thus, we do not have any pathogen results to present nor additional results regarding the spread of blacklegged ticks and Lyme disease since the last report. Summer 2020 surveillance: After a delayed start due to COVID-19, my lab was able to conduct limited field surveillance for blacklegged ticks in southern Michigan. For two months my students were able to survey ~ 60 sites spanning22 counties and collected > 3,300 ticks. The initial results showed that blacklegged ticks are now considered "established" and "reported" from two more counties, respectively. Students also conclusively identified anestablished population of lone star ticks, which is continuing to expandnorthwards from its historical southern geographical distribution. This population the students identifiedis the first documented population in Michigan. Throughout the summer, students and I kept the state health department apprised of our findings and also communicatedwith the local health department where the established lone star tick populationhad been detected. ii) to monitor the invasion of Lyme disease through active surveillance of ticks on canine companion animals. My graduate student (Porter) presented initial results to two meetings in Fall 2019, which showed moderate agreement between canine-tick surveillance and publically available canine seropositivity data for B. burgdorferi for the state of Michigan.Before she could finish, she was hired by a state health department and was consumed by running theirCOVID-19 surveillance program. She plans on finishing by this coming summer (2021). B. Ecology of Lyme disease and other pathogens associated with the blacklegged tick i) to compare the ecology of blacklegged ticks and the Lyme disease pathogen,Borrelia burgdorferi, in northern and southern regions of the US. My collaborators published (and/or have accepted)two papers originating and/or were informed from this work (see publications: Ginsberg et al. 2020; Ogden et al. accepted), and we have another one in review. ii) to investigate the phenotypic differences in traits among blacklegged ticks derived from different areas throughout its range. Nothing to report. iii) to investigate the ecology of Borrelia miyamotoi, another emerging pathogen transmitted by the blacklegged tick. My graduate student had one paper accepted (Han et al. 2020). In summary, during these five years we have made strides in better documenting the spread of ticks and tick-borne pathogens in Michigan and contributed to a better understanding of the processes affecting the variation in Lyme disease risk between northern and southern eastern U.S. We have worked with local, state, and national health departments to share our findings as well as disseminate them at local, regional, national, and international conferences. We also have shared results at outreach events for the general public.

Publications

• Type: Journal Articles Status: Published Year Published: 2019 Citation: Moll, R., JT Eaton, JD Cepak, PD Lorch, PM Dennis, T Robinson, JI Tsao, RA Montgomery. Dynamic rodent behavioral response to predation risk: implications for disease ecology. Oecologia. 192: 67-78.
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Ginsberg, HS, EL Rulison, JL Miller, GC Pang, IM Arsnoe*, GJ Hickling, NH Ogden, RA Lebrun, JI Tsao. 2020. Local abundance of Ixodes scapularis in forests: effects of environmental moisture, vegetation characteristics, and host abundance. Ticks Tick-borne Dis. 11(1): 101271
• Type: Journal Articles Status: Published Year Published: 2020 Citation: Bron G, M Fernandez, S Larson, A. Maus, D. Gustafson, JI Tsao, M Diuk-Wasser, L Bartholomay, and S Paskewitz. Context matters: Contrasting behavioral and residential risk factors for Lyme disease between two high-incidence regions in the Northeastern and Midwestern U.S. Ticks Tick-borne Dis. 11(6): 101515
• Type: Journal Articles Status: Awaiting Publication Year Published: 2020 Citation: Ogden NH, CB Beard, HS Ginsberg, JI Tsao. Possible effects of climate change on Ixodid ticks and the pathogens they transmit: what has been projected and what has been observed. J Med Entomol. Accepted 9/9/20.
• Type: Conference Papers and Presentations Status: Other Year Published: 2020 Citation: Kobbekaduwa V, Tsao JI. (2020). A comparison of Anaplasma phagocytophilum infection in questing blacklegged ticks (Ixodes scapularis) at sites throughout the North Central, North Eastern and South Eastern USA. Annual conference of Michigans Mosquito Control Association, East Lansing, MI.
• Type: Journal Articles Status: Other Year Published: 2020 Citation: J.I. Tsao. Surveillance update for ticks in Michigan. The Michigan Mosquito Control Association, Annual Meeting, East Lansing, MI. February 2020. Invited Speaker.
• Type: Other Status: Other Year Published: 2020 Citation: Kryda, J, and JI Tsao. 2020. Community-scale distribution of Ixodes scapularis ticks in the Lansing, MI area and risk to Borrelia burgdorferi and Anaplasma phagocytophilum (Summer 2019). (Completion report written to disseminate results to local health departments, city, county, and state parks and conservation organizations).
• Type: Journal Articles Status: Awaiting Publication Year Published: 2020 Citation: Han S, GJ Hickling, HS Ginsberg, *V Kobbekaduwa, E Rulison, L Beati, NH Ogden, and JI Tsao. Seasonality of acarological risk of Borrelia miyamotoi from all questing instars of Ixodes scapularis in the north central and northeastern United States. Ticks Tick-borne Dis. Accepted: 9/12/20.
• Type: Journal Articles Status: Under Review Year Published: 2021 Citation: Sidge, JL, ES Foster, DE Buttke, A Hojgaard, CB Graham, and JI Tsao. Maintenance of Ixodes scapularis in the absence of white-tailed deer on an island in Lake Michigan. J. Med. Entomol. Submitted: 1/15/19. In revision (resubmitted 3/31/20).
• Type: Journal Articles Status: Under Review Year Published: 2020 Citation: Lantos, Paul M., Rumbaugh, Jeffrey, Bockenstedt, Linda, Falck-Ytter, Yngve, Aguero-Rosenfeld, Maria et al. 2019 Guidelines for the Prevention, Diagnosis and Treatment of Lyme Disease. Arthritis and Rheumatology. Submitted: 4/20/20.
• Type: Journal Articles Status: Under Review Year Published: 2021 Citation: Ginsberg, HS, GJ Hickling, RL Burke, NH Ogden, L Beati, RA LeBrun, IM Arsnoe, R Gerhold, S Han, K Jackson, L Maestas, T Moody, G Pang, B Ross, EL Rulison, and JI Tsao. Tick-host associations and the geographical gradient of Lyme disease in the eastern United States. PLoS Biology. Submitted 8/4/20.
• Type: Journal Articles Status: Under Review Year Published: 2021 Citation: Lantos, PM, et al. Environmental correlates of Lyme disease emergence in Southwest Virginia, 2005-2014. J. Med. Entomol. Submitted 9/15/20.
• Type: Conference Papers and Presentations Status: Other Year Published: 2019 Citation: Porter, M and JI Tsao. Using a veterinary tick surveillance network to detect emerging populations of ticks in Michigan. Michigan Lyme Disease Association Conference on Integrated Topics on Lyme Disease & Other Tick-borne Illnesses. November 16, 2019. Pontiac, MI.

Progress 10/01/18 to 09/30/19

Outputs
Target Audience:The general target audience for my research efforts are research scientists, the public at large, professionals in health care, organizations and agencies with influence on the public health of citizens. Examples of organizations include: Michigan Lyme Disease Association Michigan Department of Community Health Michigan Department of Natural Resources Centers for Disease Control and Prevention Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Graduate students have been encouraged to present their research at local meetings. Graduate students also have had the opportunity to mentor undergraduate students in research. How have the results been disseminated to communities of interest?Graduate students have presented results at conferences. We also had several conference presentations and publications from the project (see "Publications" section). What do you plan to do during the next reporting period to accomplish the goals?Continue as planned.

Impacts
What was accomplished under these goals? i) Active surveillance for blacklegged ticks in Michigan via sampling for questing blacklegged ticks in the landscape. In 2018 my lab conducted the most extensive active surveillance effort for blacklegged ticks in Michigan to date. In 2019, we continued this effort at the state level. We continued to try to identify emerging tick populations, but we shifted research objectives. In a collaboration with the CDC, we wanted to sample sites at least two times during the nymphal host-seeking season so that we could obtain better estimates of nymphal density and infection prevalences (with the Lyme disease pathogen).Thus, in total, we sampled > 495 km from 75 sites spread among 64/83 counties. Through this effort, we did document an increase in the number of counties with detectable (="reported", n= 5) and established populations of (n=5) blacklegged ticks (according to CDC criteria), suggesting that this tick is continuing to spread across the Michigan and thus that the risk for tick borne diseases continues to increase in Michigan. We still did not detect blacklegged ticks in some counties (n= 9) of the counties we resampled from 2018. Ticks are still being analyzed for pathogen, so will see how the spread of pathogens has occurred in Michigan in 2018-2019 beyond the increases in spread seen in 2017-2018.We also will obtain an update on the densities of and prevalence of infected ticks in areas where ticks are known to be established, to see if they have increased (for both measures) over time as expected based on data from other Lyme disease endemic areas). In conjunction with this effort our lab also further analyzed the infection prevalence of 2018 samples withAnaplasma phagocyophilum, another pathogen transmitted by the blacklegged tick.The CDC had assayed the ticks for multiple pathogens, but they do not strain type the Anaplasma, and we do know that there are strains that exist that are not pathogenic to humans or companion canines. So, a graduate studentin my strain-- typed our positive samples and found that in Michigan all of the strains were the pathogenic strain. ii) Active surveillance for blacklegged ticks by sampling canine companion animals in a veterinary network We have finished identifying and assaying ticks for pathogens.We have conducted the initial statistical analyses to better understand how the spatial distribution of blacklegged ticks detected by our veterinary network compares with that of serological evidence of exposure to Lyme borrelia published by the Companion Animal Parasite Council.

Publications

• Type: Journal Articles Status: Accepted Year Published: 2019 Citation: De Mee�s T,�CT�Chan,�JM�Ludwig,�JI�Tsao,�J�Patel,�J�Bhagatwala,�L�Beati. Deceptive combined effects of short allele dominance and stuttering: an example with Ixodes scapularis, the main vector of Lyme disease in the U.S.A. PCI Evol Biol.
• Type: Journal Articles Status: Accepted Year Published: 2019 Citation: Ginsberg, HS, EL Rulison, JL Miller, GC Pang, IM Arsnoe, GJ Hickling, NH Ogden, RA Lebrun, J.I. Tsao. Local abundance of Ixodes scapularis in forests: effects of environmental moisture, vegetation characteristics, and host abundance. Ticks Tick-borne Dis.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Han, S, C Lubelczyk, GJ Hickling and J.I. Tsao. Transovarial transmission rate and filial infection prevalence of Borrelia miyamotoi from Ixodes scapularis collected from hunter-harvested white-tailed deer. Ticks and Tick borne Diseases. 10(3):682-689.
• Type: Journal Articles Status: Published Year Published: 2019 Citation: Arsnoe, I.M, J.I. Tsao, G.J. Hickling. 2019. Differences in Nymphal Tick Questing Behavior Explain Geographic Variation in Lyme Disease Risk in the Eastern United States. Ticks and Tick borne Diseases. 10(3): 553-563.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: J.I. Tsao, H.S. Ginsberg, G.J. Hickling, and N. Ogden. Tick control: what methods are available and how well have they been evaluated? 48th Annual SOVE Conference. Yosemite National Park, CA. Oct. 2018. Invited speaker.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Hickling, G.J., and J.I. Tsao. Differences in nymphal tick questing behavior help explain geographic variation in Lyme disease risk. 48th Annual SOVE Conference. Yosemite National Park, CA. Oct. 2018.
• Type: Conference Papers and Presentations Status: Other Year Published: 2019 Citation: Porter M. Canine Tick Surveillance and the Distribution of Emerging Blacklegged Tick Populations in Michigan. Michigan Mosquito Control Association. Lansing, MI. Feb 2019.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Kobbekaduwa V. Distribution of Anaplasma phagocytophilum in Michigan in 2018 in Questing Black-Legged Ticks (Ixodes scapularis). Michigan Mosquito Control Association. Lansing, MI. Feb 2019.

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:The general target audience for my research efforts are the public at large, professionals in health care, organizations andagencies with influence on the public health of citizens. Examples of organizations include: Michigan Lyme Disease Association Michigan Department of Health & Human Services Michigan Department of Natural Resources Centers for Disease Control and Prevention Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Graduate students had opportunities to present their findings at local, state, regionalandnational conferences. They received awards for their presentations as well (1 local and 1 regional). A graduate student interested in conducting outreach also had several opportunities to present talks to conferences for otherprofessions and stakeholders (e.g., public health, forestry, naturalists/conservationists). Graduate students also had opportunities to mentor undergraduates. Through the Midwest Center of Excellence in Vector Borne Disease, a graduate studenthad the opportunity to participate in a research planning workshop. How have the results been disseminated to communities of interest?The data from our studies in summer and fall 2017 were used to update the Michigan Department of Health and Human Services Lyme disease risk map. I conducted outreach to the public about ticks and tick-borne diseases in Michiganfor veterinarians, students of biological field stations, outdoor recreationists, and my department.A graduate student working with me who isinterested in conducting outreach also had several opportunities to present talks to conferences for otherprofessions and stakeholders (e.g., public health, forestry, naturalists/conservationists). What do you plan to do during the next reporting period to accomplish the goals?We plan to continue what we are doing.

Impacts
What was accomplished under these goals? A. Lyme disease emergence: surveillance i) Active surveillance for blacklegged ticks in Michigan via sampling for questing blacklegged ticks in the landscape Michigan has 83 counties, many of which have not been sampled actively for blacklegged ticks. Our sampling representsthe most extensive active surveillance effort for blacklegged ticks in Michigan to date.Overall we sampled 78/83 counties at least once (176 sites). In comparison with Eisen et al. 2016, these effortsresulted in decreasing the total # of counties for which there is either no data or no blacklegged ticks collected from 44 to31; increasing the number of counties with reported ticks from 16 to 17; and increasing the number of counties with established ticks from 23 to 35. The overall increase in the number of counties reporting ticks suggests that the blacklegged tick is continuing to spread across the Michigan and thus that the risk for tick borne diseases continues to increase in Michigan. Ticks are still being analyzed for pathogen, so will see how the spread of pathogens has occurred in Michigan in 2017-2018 beyond the increases in spread seen in 2016-2017. ii) Active surveillance for blacklegged ticks by sampling canine companion animals in a veterinary network We completed another two rounds of sampling - fall (2017) and spring (2018)- for ticks conducted by volunteerveterinary clinics throughout the state. These ticks are still be identified and assayed for pathogens.

Publications

• Type: Journal Articles Status: Published Year Published: 2018 Citation: Nicholas H Ogden, Genevieve Pang, Howard S Ginsberg, Graham J Hickling, Russell L Burke, Lorenza Beati, Jean I Tsao; Evidence for Geographic Variation in Life-Cycle Processes Affecting Phenology of the Lyme Disease Vector Ixodes scapularis (Acari: Ixodidae) in the United States, Journal of Medical Entomology, , tjy104, https://doi-org.proxy2.cl.msu.edu/10.1093/jme/tjy104
• Type: Journal Articles Status: Under Review Year Published: 2018 Citation: Han, S, C Lubelczyk, GJ Hickling and JI Tsao. Transovarial transmission rate and filial infection prevalence of Borrelia miyamotoi from Ixodes scapularis collected from hunter-harvested white-tailed deer. Ticks and Tick borne Diseases.
• Type: Journal Articles Status: Under Review Year Published: 2018 Citation: Arsnoe, I, JI Tsao, GH Hickling. Differences in Nymphal Tick Questing Behavior Explain Geographic Variation in Lyme Disease Risk in the Eastern United States. Ticks and Tick borne Diseases.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: 1. J.I. Tsao, L. Beati, R. Burke, H.S. Ginsberg, G.J. Hickling, and N. Ogden. Multiple ecological factors contribute to the gradient of Lyme borreliosis throughout the eastern USA. 15th International Conference on Lyme Borreliosis and other Tick-borne Diseases. Atlanta, GA. Sept. 2018. (Oral)
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: 1. J.I. Tsao and S. Han. Maintenance of Borrelia miyamotoi in nature. 2018 Biology of Spirochetes Gordon Research Conference. Ventura, CA. Jan. 2018. Invited speaker.
• Type: Other Status: Submitted Year Published: 2018 Citation: Burrell I, Drankhan H, Kuechle C, Kurtz K, Olson A, Scherger E, Sinnamon M, and Vetter N. 2018. Surveillance update: the state of the risk of Lyme disease at Ft. Custer State Recreation Area. J.I. Tsao ed. Completion report. Michigan Department of Health and Human Services and Michigan Department of Natural Resources.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Han, S., C. Lubelczyk, G. J. Hickling and J.I. Tsao. Transovarial transmission rate and filial infection prevalence of Borrelia miyamotoi from Ixodes scapularis collected from hunter-harvested white-tailed deer. Michigan Mosquito Control Conference. Lansing, MI.
• Type: Other Status: Other Year Published: 2018 Citation: Pang, G., H.S. Ginsberg, G.J. Hickling, N.H. Ogden, J.I. Tsao. An investigation of key abiotic and genetic factors affecting blacklegged tick population dynamics in the Eastern United States. Michigan Mosquito Control Conference. Lansing, MI.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Porter, M. and J.I. Tsao. Active Surveillance for Emerging Ixodes scapularis populations in eastern Michigan. NCB-ESA 73rd Annual Meeting. Madison, MI.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Porter, M. and J.I. Tsao. Active Surveillance for Emerging Ixodes scapularis populations in Michigan using a veterinary canine network. NCB-ESA 73rd Annual Meeting. Madison, MI.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Porter, M. and J.I. Tsao. Active Surveillance for Emerging Ixodes scapularis populations in Michigan using a veterinary canine network. 15th International Conference on Lyme Borreliosis and other Tick-borne Diseases. Atlanta, GA.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Kobbekaduwa, V. and J.I. Tsao. Anaplasma phagocytophilum infection in questing blacklegged ticks, Ixodes scapularis, and mammal hosts (2010-2012) in Ft. McCoy, Wisconsin, USA. 15th International Conference on Lyme Borreliosis and other Tick-borne Diseases. Atlanta, GA.
• Type: Conference Papers and Presentations Status: Other Year Published: 2018 Citation: Ogden, N.H., H.S. Ginsberg, G.J. Hickling, R.L. Burke, L. Beati-Ziegler, G. Pang*, and J.I. Tsao. Evidence for geographic variation in life-cycle processes affecting phenology of the Lyme disease vector Ixodes scapularis in the USA. 15th International Conference on Lyme Borreliosis and other Tick-borne Diseases. Atlanta, GA.

Progress 10/01/16 to 09/30/17

Outputs
Target Audience:The general target audience for my research efforts are the public at large, professionals in health care, organizations and agencies with influence on the public health of citizens. Examples of organizations include: Michigan Lyme Disease Association Michigan Department of Health & Human Services Michigan Department of Natural Resources Centers for Disease Control and Prevention Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Graduate students have been encouraged to present their research at local, national, and international meetings. Examples of presentations given in 2017 are found in "Accomplishments" section above. Graduate students also have had the opportunity to mentor undergraduate students in research. How have the results been disseminated to communities of interest?There are been a few publications (see products section). We also frequently conduct outreach with veterinarians, the MSU biological field station, and other groups who request such talks/interactions. What do you plan to do during the next reporting period to accomplish the goals?Continueas we have been doing.

Impacts
What was accomplished under these goals? A). My lab continued to conduct environmental sampling to monitor the invasion of the blacklegged tick in central southern and southeastern Michigan. Drag surveillance conducted in Michigan during 2/22/2017 and 7/24/2017 with a total 179,067 m dragged (146,667 m2 - switched to 0.75 m2 drag cloths in May 2017) at 69 sites (state parks/wildlife areas, county and city parks, public hunting land) in 46 counties in Michigan (68/69 sites in Lower Peninsula). Majority of counties surveyed were in eastern Lower Peninsula. Five sites were located in southwestern Lower Peninsula throughout sampling period, with Ixodes scapularis ticks detected at 5/5 sites. Ticks detected included I. scapularis (n=269), Dermacentor variabilis (n=113), I. dentatus (n=2), Amblyomma americanum (n=1), and Haemaphysalis leporispalustris (n=2). Ixodes scapularis detected in 14 counties in eastern/central Michigan (3 which were considered to have known disease risk by MI Dept of Health and Human Services. Only 1 I. scapularis tick assayed (n=198) positive for Borrelia burgdorferi from south-central Michigan, with 5/166 from southwestern sites positive for B. burgdorferi. My lab continued to solicit samples from a network of veterinarians throughout the state of Michigan for ticks during the fall and spring adult activity period of the blacklegged tick. These data helped inform some of the field sites at which drag sampling was conducted. B)We have just continued to analyze results of samples obtained in the past. We have better described the prevalence of Borrelia miyamotoi in questing ticks and hosts as well as the transovarial transmission rate and filial infection prevalence in blacklegged ticks from a highly endemic site in the Midwest. We continued to make progress on learning about the biology of Borrelia miyamotoi; including learning how to culture it. We also have better described the prevalence of Anaplasma phagocytophilum in questing ticks and on-host ticks at the same field site. We continued to make progress on analyzing and comparing the behavior and development phenotypes of blacklegged ticks from the northern and southern US.

Publications

• Type: Journal Articles Status: Published Year Published: 2017 Citation: Couret, J., M.C. Dyer, T.N. Mather, J.I. Tsao, S. Han*, R. Lebrun, H.S. Ginsberg. Using tick scutal indices of larval Ixodes scapularis (Acari: Ixodidae) as a method of determining pathogen acquisition. J. Med. Entomol. 54(4):10551060.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Lantos, PM, J.I. Tsao, LE Nigrovic, PG Auwaerter, V Fowler, F Ruffin, E Foster, GJ Hickling. Geographic Expansion of Lyme disease in Michigan, 2000-2014. Open Forum Infectious Diseases. 4(1) ofw269.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Ginsberg, H.S., M. Albert, L. Acevedo, M.C. Dyer, I.M. Arsnoe*, J.I. Tsao, T.N. Mather, R.A. LeBrun. Environmental factors affecting survival of immature Ixodes scapularis and implications for geographical distribution of Lyme disease; an evolutionary hypothesis. PLoS One. 12(1):e0168723. DOI: 10.1371/jounal.pone.0168723.
• Type: Other Status: Under Review Year Published: 2017 Citation: Angie Burkett, Bear Daniels, Lora Gurley, Sierra Imanse, Nicole Nelson, Jodee Schmidt. 2017. Ecological survey of blacklegged ticks (Ixodes scapularis), Anaplasma phagocytophilum, and Borrelia burgdorferi in Southeast Michigan in response to a clinical case of canine anaplasmosis. J.I. Tsao and G.J. Hickling eds. Completion report. Michigan Department of Health and Human Services.

Progress 02/01/16 to 09/30/16

Outputs
Target Audience:The general target audience for my research efforts are the public at large, professionals in health care, organizations and agencies with influence on the public health of citizens. Examples of organizations include: Michigan Lyme Disease Association Michigan Department of Health & Human Services Michigan Department of Natural Resources Centers for Disease Control and Prevention Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?1. Lyme disease emergence: surveillance Two MPH students as well as two DVM summer students in addition to my graduate students received training. Also 6 veterinary students in a veterinary rotation course were able to be trained on conducing field investigations for a vector-borne disease. 2. Ecology of Lyme disease and other pathogens associated with the blacklegged tick My four graduate students continued to receive training on conducting research in the disease ecology of vector-borne diseases. How have the results been disseminated to communities of interest?1. Lyme disease emergence: surveillance Report to Michigan Department of Community Health, Fenner Nature Center, Michigan Department of Natural Resources (Waterloo State Recreation Area and Pinckney State Recreation Area), Michigan Lyme Disease Association 2. Ecology of Lyme disease and other pathogens associated with the blacklegged tick: nothing to report What do you plan to do during the next reporting period to accomplish the goals?Continue as we have been doing.

Impacts
What was accomplished under these goals? 1. Lyme disease emergence: surveillance My lab continued to conduct environmental sampling at a limited number of locations to monitor the invasion of the blacklegged tick in central southern and southeastern Michigan. My lab developed a network of veterinarians throughout the state of Michigan and asked them to actively survey companion canines for ticks during the spring adult activity period of the blacklegged tick. My lab also coordinated a field investigation in conjunction with veterinary students of two new field sites indicated to possibly harbor new populations of the blacklegged tick. 2. Ecology of Lyme disease and other pathogens associated with the blacklegged tick We continued to make progress on processing tick and host samples from the northern and southern US to quantify the prevalence of blacklegged ticks for infection with Borrelia burgdorferi and B. miyamotoi. We continued to make progress on analyzing and comparing the behavior and development phenotypes of blacklegged ticks from the northern and southern US. We continued to make progress on learning about the biology of Borrelia miyamotoi; including learning how to culture it. b. Dissemination of results: We have not yet finished analyzing these results.

Publications

• Type: Journal Articles Status: Published Year Published: 2016 Citation: Han*, S., G.J. Hickling, J.I. Tsao. 2016. High prevalence of Borrelia miyamotoi in adult blacklegged ticks (Ixodes scapularis) sampled from white-tailed deer (Odocoileus virginianus). Emerg. Inf. Dis. 22(2):316-318.
• Type: Journal Articles Status: Published Year Published: 2016 Citation: Gray, J.S., O. Kahl, R.S. Lane, M.L. Levin, J.I. Tsao. 2016. Diapause in Ticks of the Medically Important Ixodes ricinus Species Complex. Ticks and Tick-Borne Diseases. 7:992-1003.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2016 Citation: J.I. Tsao. Predicting geographical differences in the spread and acquisition of Ixodes scapularis-borne disease: how phenology matters. 1st Nordtick Conference on Ticks and Tick-borne Diseases. Landskrona, Sweden. February 2016. Invited Keynote lecture on Tick Ecology & Biology.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2016 Citation: J.I. Tsao. The relentless spread of Ixodes scapularis: predicting future risk of Lyme disease. Tick Summit V. Patuxent, MD. March 2016. Invited speaker.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2016 Citation: J.I. Tsao. Pathogen-tick interactions. Entomological Society of America Integrated Tick Management Symposium. May 2016. Invited speaker.
• Type: Journal Articles Status: Submitted Year Published: 2016 Citation: Ginsberg, H.S., M. Albert, L. Acevedo, M.C. Dyer, I.M. Arsenoe, J.I. Tsao, T.N. Mather, R.A. LeBrun. Environmental factors affecting survival of immature Ixodes scapularis and implications for geographical distribution of Lyme disease; an evolutionary hypothesis. Submitted September 2016 to J. Med. Entomol.
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2016 Citation: Pang, G., H.S. Ginsberg, G.J. Hickling, N.H. Ogden, J.I. Tsao. An investigation of key abiotic and genetic factors affecting blacklegged tick population dynamics in the Eastern United States. XXV International Congress of Entomology. Orlando, FL. Sept. 2016. (Graduate student Pang was an invited speaker.)
• Type: Conference Papers and Presentations Status: Accepted Year Published: 2016 Citation: Brian Allan, Natalie Pawlikowski, Allison Gardner, Sarah Hamer, Graham Hickling,James Miller, Anna Schotthoefer and Jean Tsao. Invasion of the BLTs: Patterns and Mechanisms of the Geographic Expansion of Lyme Disease in the Midwestern U.S. XXV International Congress of Entomology. Orlando, FL. Sept. 2016.
• Type: Other Status: Submitted Year Published: 2016 Citation: Fenske C, Girard L, Glomb J, Kellogg C, O-Neill TW, Ryan T. 2016. Blacklegged Ticks and Lyme Disease Pathogen Status at Fenner Nature Center, Lansing Michigan: Late summer field investigations 2015-2016. J.I. Tsao and G.J. Hickling eds. Completion report. Fenner Nature Center.
• Type: Other Status: Submitted Year Published: 2016 Citation: Fenske C, Girard L, Glomb J, Kellogg C, O-Neill TW, Ryan T. 2016. Abundance of blacklegged ticks and prevalence of the Lyme disease pathogen in mid- and southeastern Michigan. J.I. Tsao and G.J. Hickling eds. Completion report. Michigan Department of Health and Human Services.