24. How an extreme weather spell in winter can influence vector tick abundance and tick-borne disease incidence

Abstract Urbanization alters components of natural ecosystems which can affect tick abundance and tick-borne disease prevalence. Likely due to these changes, tick-borne pathogen prevalence has increased in many U.S. urban areas. Despite the growing public health importance of tick-borne diseases, little is known about how they are influenced by urbanization in North America, especially in the central U.S. where several pathogens occur at or near their highest levels of incidence nationally. To determine whether urban development influences tick infection with bacteria and protozoa, we collected ticks at 16 parks across a gradient of urbanization intensity in Oklahoma City, Oklahoma, USA and tested them using a variety of PCR assays. Adult ticks tested positive for Rickettsia parkeri, R. amblyommatis, R. rhiphicephali, ‘Candidatus R. andeanae’, Ehrlichia chaffeensis, E. ewingii, Panola Mountain Ehrlichia, ‘Borrelia lonestari’, Theileria cervi, Babesia spp. Coco, and Cytauxzoon felis. These results indicate the presence of a high diversity of tick-borne bacteria and protozoa across an expanding urban area in the U.S. Great Plains. Although there appeared to be some risk of encountering tick-borne microorganisms across the entire urbanization gradient, E. chaffeensis, E. ewingii, and T. cervi-infected ticks and microbe diversity decreased with increasing urbanization intensity. We identified a low rate of coinfection between different microorganisms, with coinfected ticks mainly collected from sites in the least-urbanized areas. This study suggests the need for awareness of tick-borne disease risk throughout urban areas in the central U.S., and highlights a need for studies of tick host habitat use and movement in cities.

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Effects of Climate on the Variation in Abundance of Three Tick Species in Illinois

Journal of Medical Entomology ◽

10.1093/jme/tjab189 ◽

2021 ◽

Author(s):

E A Bacon ◽

H Kopsco ◽

P Gronemeyer ◽

N Mateus-Pinilla ◽

R L Smith

Keyword(s):

Tick Species ◽

Ixodes Scapularis ◽

Species Abundance ◽

Dermacentor Variabilis ◽

Amblyomma Americanum ◽

Differential Impact ◽

Tick Abundance ◽

Network Analyses ◽

Average Temperature ◽

Tick Borne Disease

Abstract The range of ticks in North America has been steadily increasing likely, in part, due to climate change. Along with it, there has been a rise in cases of tick-borne disease. Among those medically important tick species of particular concern are Ixodes scapularis Say (Acari: Ixodidae), Dermacentor variabilis Say (Acari: Ixodidae), and Amblyomma americanum Linneaus (Acari: Ixodidae). The aim of this study was to determine if climate factors explain existing differences in abundance of the three aforementioned tick species between two climatically different regions of Illinois (Central and Southern), and if climate variables impact each species differently. We used both zero-inflated regression approaches and Bayesian network analyses to assess relationships among environmental variables and tick abundance. Results suggested that the maximum average temperature and total precipitation are associated with differential impact on species abundance and that this difference varied by region. Results also reinforced a differential level of resistance to desiccation among these tick species. Our findings help to further define risk periods of tick exposure for the general public, and reinforce the importance of responding to each tick species differently.

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Lyme disease in Poland in 2018

Przeglad Epidemiologiczny ◽

10.32394/pe.75.06 ◽

2021 ◽

pp. 58-62

Author(s):

Jakub Zbrzeźniak ◽

Iwona Paradowska-Stankiewicz

Keyword(s):

Climate Change ◽

Lyme Disease ◽

Surveillance System ◽

Endemic Area ◽

Disease Incidence ◽

Disease Diagnosis ◽

Clear Trend ◽

Tick Borne Disease ◽

The Right ◽

Epidemiological Situation

INTRODUCTION. Lyme disease is the most common tick-borne disease, caused by spirochetes of the genus Borrelia, transmitted by ticks of the Ixodes genus. According to ECDC, Poland should be considered as an endemic area. The risk of Lyme disease incidence in-creases with tick habitats increase, which is a response to environmental factors and climate change. AIM OF THE STUDY. The aim of the study is to assess the epidemiological situation of Lyme disease in Poland in 2018 compared to the situation in previous years. MATERIAL AND METHODS. The epidemiological situation of Lyme disease in Poland was assessed on the basis of the data sent to NIPH-NIH by voivodeship sanitary-epidemiological stations and published in the bulletin ‘Infectious diseases and poisoning in Poland in 2018’ . RESULTS. In 2018; 20,150 Lyme disease cases was registered, 2,124 people were hospitalized. You can also see an increase in cases in the second and third quarter in favor of the fourth quarter. The epidemiological situation in Western European countries is similar to the situation in Poland. SUMMARY AND CONCLUSION. The inability to determine the clear trend of the epidemiological situation in Poland indicates the sensitivity of the surveillance system, but also the difficulty in new cases diagnosis. You can also see a decrease in the number of cases, which may be a sign of having the right tools or experience in the Lyme disease diagnosis.

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The prevalence and clinical characteristics of tick-borne diseases at One Sentinel Hospital in Northeastern China

Parasitology ◽

10.1017/s0031182018001178 ◽

2018 ◽

Vol 146 (2) ◽

pp. 161-167 ◽

Cited By ~ 2

Author(s):

Hong-Bo Liu ◽

Ran Wei ◽

Xue-Bing Ni ◽

Yuan-Chun Zheng ◽

Qiu-Bo Huo ◽

...

Keyword(s):

Clinical Symptoms ◽

Spotted Fever ◽

Erythema Migrans ◽

Northeastern China ◽

Spotted Fever Group ◽

Tick Abundance ◽

Granulocytic Anaplasmosis ◽

Indirect Immunofluorescent Assay ◽

Tick Borne Disease ◽

Human Infections

AbstractNortheastern China is a region of high tick abundance, multiple tick-borne pathogens and likely human infections. The spectrum of diseases caused by tick-borne pathogens has not been objectively evaluated in this region for clinical management and for comparison with other regions globally where tick-transmitted diseases are common. Based on clinical symptoms, PCR, indirect immunofluorescent assay and (or) blood smear, we identified and described tick-borne diseases from patients with recent tick bite seen at Mudanjiang Forestry Central Hospital. From May 2010 to September 2011, 42% (75/180) of patients were diagnosed with a specific tick-borne disease, including Lyme borreliosis, tick-borne encephalitis, human granulocytic anaplasmosis, human babesiosis and spotted fever group rickettsiosis. When we compared clinical and laboratory features to identify factors that might discriminate tick-transmitted infections from those lacking that evidence, we revealed that erythema migrans and neurological manifestations were statistically significantly differently presented between those with and without documented aetiologies (P< 0.001,P= 0.003). Twelve patients (6.7%, 12/180) were co-infected with two tick-borne pathogens. We demonstrated the poor ability of clinicians to identify the specific tick-borne disease. In addition, it is necessary to develop specific laboratory assays for optimal diagnosis of tick-borne diseases.

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Integrated Tick Management in South Central Wisconsin: Impact of Invasive Vegetation Removal and Host-Targeted Acaricides on the Density of Questing Ixodes scapularis (Acari: Ixodidae) Nymphs

Journal of Medical Entomology ◽

10.1093/jme/tjab131 ◽

2021 ◽

Author(s):

Jordan T Mandli ◽

Xia Lee ◽

Gebbiena M Bron ◽

Susan M Paskewitz

Keyword(s):

Ixodes Scapularis ◽

Disease Incidence ◽

Management Strategies ◽

Sensu Stricto ◽

Management Approach ◽

Infection Prevalence ◽

Vegetation Removal ◽

South Central ◽

Integrated Tick Management ◽

Tick Borne Disease

Abstract As tick-borne disease incidence increases and pathogens expand into new areas, the need for effective tick management strategies is paramount. In this 5-yr study (2014–2018) conducted in south central Wisconsin, we assessed whether an integrated tick management approach, deployed during peak tick activity (May–August), was more effective at reducing black-legged ticks (Ixodes scapularis Say (Ixodida: Ixodidae)), than individual interventions. Using a factorial design, invasive vegetation removal (Amur honeysuckle, Lonicera maackii Ruprecht (Dipsacales: Caprifoliaceae) and common buckthorn, Rhamnus cathartica Linnaeus (Rosales: Rhamnaceae)) was coupled with deployments of permethrin-treated cotton nesting materials (tick tubes) that target the white-footed mouse (Peromyscus leucopus Rafinesque (Rodentia: Cricetidae)). Results show that the probability of encountering a larval tick by drag sampling was unaffected by treatments at the cumulative 5-yr level. However, vegetation removal significantly reduced larval encounters in 2014, 2015, and 2018, by 33%, 57%, and 61% respectively, and reduced the density of questing nymphal (DON) ticks by 45% in 2015 compared to controls. Despite the limited effect on DON, vegetation removal significantly reduced the cumulative 5-yr density of Borrelia burgdorferi sensu stricto infected nymphs (DIN) (70%) compared to controls as a result of decreased nymphal infection prevalence. Sites treated with tick tubes had lower DIN (66%) and DON (54%) across the study and nymphs were reduced every year following the initial year of deployment compared to controls. Combining treatments did not further reduce DIN or DONs. We conclude that long-term integration of tick tubes with invasive vegetation removal does not provide additional benefit over individual treatments alone.

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Tick abundance, pathogen prevalence, and disease incidence in two contrasting regions at the northern distribution range of Europe

Parasites & Vectors ◽

10.1186/s13071-018-2890-9 ◽

2018 ◽

Vol 11 (1) ◽

Cited By ~ 9

Author(s):

Atle Mysterud ◽

Vetle Malmer Stigum ◽

Ingrid Vikingsdal Seland ◽

Anders Herland ◽

W. Ryan Easterday ◽

...

Keyword(s):

Disease Incidence ◽

Distribution Range ◽

Tick Abundance ◽

Northern Distribution ◽

Pathogen Prevalence

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Persistence and transmission of tick-borne viruses: Ixodes ricinus and louping-ill virus in red grouse populations

Parasitology ◽

10.1017/s0031182000075818 ◽

1995 ◽

Vol 111 (S1) ◽

pp. S49-S58 ◽

Cited By ~ 55

Author(s):

P. J. Hudson ◽

R. Norman ◽

M. K. Laurenson ◽

D. Newborn ◽

M. Gaunt ◽

...

Keyword(s):

Ixodes Ricinus ◽

Temporal Variations ◽

Mammalian Host ◽

Tick Population ◽

Red Grouse ◽

Virus Persistence ◽

Relative Significance ◽

Tick Abundance ◽

Tick Borne Disease ◽

Louping Ill

SUMMARYThe population dynamics of tick-borne disease agents and in particular the mechanisms which influence their persistence are examined with reference to the flavivirus that causes louping-ill in red grouse and sheep. Pockets of infection cause heavy mortality and the infection probably persists as a consequence of immigration of susceptible hosts. Seroprevalence is positively associated with temporal variations in vectors per host, although variation between areas is associated with the abundance of mountain hares. The presence of alternative tick hosts, particularly large mammals, provides additional hosts for increasing tick abundance. Grouse alone can not support the vectors and the pathogen but both can persist when a non-viraemic mammalian host supports the tick population and a sufficiently high number of nymphs bite grouse. These alternative hosts may also amplify virus through non-viraemic transmission by the process of co-feeding, although the relative significance of this has yet to be determined. Another possible route of infection is through the ingestion of vectors when feeding or preening. Trans-ovarial transmission is a potentially important mechanism for virus persistence but has not been recorded with louping-ill and Ixodes ricinus. The influence of non-viraemic hosts, both in the multiplication of vectors and the amplification of virus through non-viraemic transmission are considered significant for virus persistence.

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Decoupling of Blacklegged Tick Abundance and Lyme Disease Incidence in Southern Maine, USA

Journal of Medical Entomology ◽

10.1093/jme/tjz218 ◽

2019 ◽

Vol 57 (3) ◽

pp. 755-765 ◽

Cited By ~ 2

Author(s):

Susan P Elias ◽

Kirk A Maasch ◽

Norman T Anderson ◽

Peter W Rand ◽

Eleanor H Lacombe ◽

...

Keyword(s):

Lyme Disease ◽

Ixodes Scapularis ◽

Disease Incidence ◽

Temporal Trends ◽

Adult Tick ◽

Surveillance Data ◽

Tick Abundance ◽

Blacklegged Tick ◽

Rising Incidence ◽

A Site

Abstract Lyme disease is caused by the bacterial spirochete Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt, and Brenner (Spirocheatales: Spirochaetaceae) which is transmitted through the bite of an infected blacklegged tick Ixodes scapularis Say (Ixodida: Ixodidae). Maine, USA, is a high Lyme disease incidence state, with rising incidence of Lyme disease and other tick-borne illnesses associated with increasing I. scapularis abundance and northward range expansion. Members of the public submitted ticks to a tick identification program (1990–2013). From these passive surveillance data, we characterized temporal trends in I. scapularis submission rate (an index of abundance), comparing Maine’s northern tier (seven counties) versus southern tier (nine counties). In the northern tier, the I. scapularis submission rate increased throughout the duration of the time series, suggesting I. scapularis was emergent but not established. By contrast, in the southern tier, submission rate increased initially but leveled off after 10–14 yr, suggesting I. scapularis was established by the mid-2000s. Active (field) surveillance data from a site in the southern tier—bird tick burdens and questing adult tick collections—corroborated this leveling pattern. Lyme disease incidence and I. scapularis submission rate were temporally correlated in the northern but not southern tier. This suggested a decoupling of reported disease incidence and entomological risk.

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Ticks and tick-borne pathogens in popular recreational areas in Tallinn, Estonia: an underestimated risk of tick-borne diseases

10.21203/rs.3.rs-543083/v1 ◽

2021 ◽

Author(s):

Maria Vikentjeva ◽

Olga Bragina ◽

Julia Geller

Keyword(s):

Lyme Borreliosis ◽

Tick Species ◽

Well Being ◽

Natural Environments ◽

Tick Abundance ◽

Outdoor Sports ◽

Tick Borne Encephalitis ◽

Morphological Criteria ◽

Green Areas ◽

Tick Borne Disease

Abstract BACKGROUND For over several decades ticks are noticed to be widely present in the green spaces of urban environments. Rodents that provide essential blood-meals for subadult ticks and serve as natural reservoirs for many known tick-borne diseases, such as Lyme borreliosis and tick-borne encephalitis, might be quite abundant in green areas within urban settlements. In that way, the improvement of green infrastructures within cities possess not only to better human well-being but might also increase the risk of being bitten by a tick and having a tick-borne disease. This study aimed to provide a first insight into ticks and tick-borne pathogen presence and prevalence in popular recreational green areas in Tallinn, Estonia. METHODS Ticks were collected by flagging in May-June, 2018. Tick species identification was performed on morphological criteria. Tick-borne pathogens detection was performed by pathogen-specific PCR and qPCR reactions. RESULTS 855 Ixodes ticks were collected from a total area of 12 000 m2. An estimated tick abundance were up to 18.5 ticks per 100 m2. 34.3% of all ticks were revealed positive for at least one tick-borne pathogen. Borrelia burgdorferi s.l. was found in 17.5%, Rickettsia sp in 13.8%, Neoehrlichia mikurensis on 5.4%, B. miyamotoi in 2.5%, Anaplasma phagocytophilum in 0.6% and tick-borne encephalitis virus in 0.5% of ticks. CONCLUSION This study reports the occurrence of Ixodes tick species in popular recreational, outdoor sports and leisure areas in the largest city of Estonia, with abundance and prevalence rates compatible or even exceeding those detected previously in the most endemic foci in the natural environments. Taking into account increasing Lyme borreliosis incidence, the risk of acquiring a tick bite and being infected with a tick-borne disease in urban recreational sites should not be ignored and proper information about the precautions might be considered.

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