Changing distributions of ticks: causes and consequences

Phenology and habitat associations of the invasive Asian longhorned tick from Ohio, USA

Geographically expanding and invading ticks are a global concern. The Asian longhorned tick (ALT, Haemaphysalis longicornis) was introduced to the mid-Atlantic US between 2010 and 2017 and recently invaded Ohio, an inland state. To date, ALTs in the US have been associated with livestock exsanguination and transmission of the agent of bovine theileriosis. To inform management, studies describing tick ecology and epidemiology of associated disease agents are critical. In this study, we described phenology, habitat and host associations, and tested for agents of medical and veterinary concern at the site of the first known established ALT population in Ohio, where pesticide treatment was applied in early fall 2021. In spring-fall 2022, we sampled wildlife (small mammals) and collected ticks from forest, edge, and grassland habitats. We also opportunistically sampled harvested white-tailed deer at nearby processing stations and fresh wildlife carcasses found near roads. Field-collected ALTs were tested for five agents using real-time PCR. We found that ALT nymphs emerged in June, followed by adults, and concluded with larvae in the fall. ALTs were detected in all habitats but not in wildlife. We also found a 4.88% (2/41) prevalence of Anaplasma phagocytophilum across ALT adults and nymphs. Host and habitat associations were similar to other studies in the eastern United States, but two potential differences in phenology were identified. Whether ALTs will acquire more endemic disease agents requires further investigations. Our findings provide the first evidence regarding ALT life history from the Midwest region of the United States and can inform exposure risk and guide integrated management.

Effects of Peromyscus spp. (Rodentia: Cricetidae) presence, land use, and ecotone on Ixodes scapularis (Acari: Ixodidae) ecology in an emergent area for tick-borne disease

As the range of Ixodes scapularis Say expands, host abundance and land use can play important roles in regions where ticks and their associated pathogens are emerging. Small mammal hosts serve as reservoirs of tick-borne pathogens, with Peromyscus leucopus Rafinesque often considered a primary reservoir. A sympatric species Peromyscus maniculatus Wagner is also a competent reservoir and is notoriously difficult to differentiate from P. leucopus. Anthropogenic land use can alter host and habitat availability, potentially changing tick exposure risk. We tested the hypotheses that tick infestation and pathogen prevalence differ between the two Peromyscus spp. and that host-seeking I. scapularis density and pathogen prevalence differ across land use and ecotone gradients. We live trapped small mammals and collected ticks across 3 land-use classifications and ecotones in Maine, an emergent area for tick-borne disease. We tested each small mammal and tick sample for Borrelia burgdorferi, Anaplasma phagocytophilum, and Babesia microti. While both Peromyscus spp. serve as hosts for immature ticks, P. leucopus exhibited a higher tick infestation frequency and intensity. We did not detect any significant difference in pathogen infection prevalence between the two species. The density of I. scapularis nymphs and the density of infected nymphs did not differ significantly between land-use types, though did differ across ecotones. We also noted a significant north/south gradient, with higher tick densities and pathogen prevalence at the southern end of the study area. Our study highlights the potential variability in tick density and pathogen prevalence across fine spatial scales within an emerging region for tick-borne disease.

Phenotypic and genotypic characterization of ticks and tick-borne pathogens from cattle in selected villages of Greater Letaba Municipality in Limpopo Province, South Africa

Ticks are blood ectoparasites that feed on domestic, wild animals and humans. They spread a variety of infections such as protozoa, viruses, and bacteria. Moreover, cattle reared by smallholder farmers are susceptible to ticks and tick-borne pathogens. Therefore, accurate identification of ticks and detection of tick-borne pathogens is crucial. The main aim of this study was to identify and characterize ticks and tick-borne pathogens from selected villages in Greater Letaba Municipality, Limpopo Province, using morphological and molecular techniques. A total of 233 ticks were collected from cattle and identified morphologically using appropriate morphological keys. The following tick species were identified: Amblyomma hebraeum, Hyalomma rufipes, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus (Boophilus) microplus, Rhipicephalus evertsi evertsi, and Rhipicephalus sanguineus. Rhipicephalus spp. was the most common species accounting to 73.8% of the identified ticks. The genomic DNA was extracted from the whole tick for tick identification and from midguts of the ticks for the detection of tick-borne pathogens, followed by amplification and sequencing. A total of 27 samples were positive for tick-borne pathogens: 23 samples tested positive for Theileria and four samples tested positive for Ehrlichia. Anaplasma and Rickettsial OmpB could not be detected from any of the samples. There was no obvious grouping of ticks and tick-borne pathogens on the bases of their locality. The findings of this study confirm previous reports that indicated that cattle reared by smallholder farmers harbor various ticks and tick-borne pathogens of veterinary, public health, and economic importance. Regular monitoring of tick infestations in villages around the study areas is recommended to avoid disease outbreaks.

The Diel Activity Pattern of Haemaphysalis longicornis and Its Relationship with Climatic Factors

Haemaphysalis longicornis is one of the most medically important carriers of various pathogens. Although H. longicornis is an important vector, only basic ecological and biological information has been obtained, primarily focusing on its abundance and distribution. This study determined the most active time and meteorological conditions for the diel activity of H. longicornis. The diel activity pattern of H. longicornis was the highest between 10:00 and 14:00, and the lowest between 22:00 and 02:00. The major activity temperature of H. longicornis was between 25 °C and 40 °C, with the highest activity at 35 °C. The relative humidity was between 30% and 70% during the active period. Temperature had the highest correlation with diel activity (R = 0.679), followed by humidity (R = -0.649) and light intensity (R = 0.572). Our results provide basic information for the development of tick-borne disease vector control programs and tick surveillance.

Infestation prevalence, spatio-temporal distribution, phylogenetic positioning, and pathogen investigation of Argas persicus ticks in domestic hens (Gallus gallus domesticus) from Pakistan

Soft ticks pose significant health risks as vectors of various pathogens. This study explored the spatio-temporal distribution and genetic relationships of the soft tick species Argas persicus infesting domestic hens (Gallus gallus domesticus) across different districts in Pakistan. An examination of 778 hens revealed a notable tick infestation prevalence of 70.82%, with a total of 1299 ticks collected from 551 hens. The overall mean intensity was 2.19 soft ticks per infested chicken, and the overall mean abundance was 1.61 soft ticks per examined hen. Morphological identification confirmed all collected ticks (n = 1210) as A. persicus, comprising 719 males, 333 females, 121 nymphs, and 38 larvae. The Haveli, Muzaffarabad, and Kotli districts had the highest infestation rates, while Bagh had the lowest. Molecular analyses of tick DNA, focusing on 16S rDNA and 12S rDNA sequences, revealed genetic similarities among A. persicus soft ticks from Pakistan and other regions, providing insights into their evolutionary history. Importantly, no Babesia, Rickettsia, or Anaplasma infections were detected in the examined samples. These findings enhance the understanding of soft tick infestation patterns and the genetic diversity of A. persicus in the studied region.

Prevalence of tick-borne pathogens in ticks collected from the wild mountain ungulates mouflon and chamois in 4 regions of France

Ticks are major vectors of various pathogens of health importance, such as bacteria, viruses and parasites. The problems associated with ticks and vector-borne pathogens are increasing in mountain areas, particularly in connection with global climate change. We collected ticks (n = 2,081) from chamois and mouflon in 4 mountainous areas of France. We identified 6 tick species: Ixodes ricinus, Rhipicephalus bursa, Rh. sanguineus s.l., Haemaphysalis sulcata, H. punctata and Dermacentor marginatus. We observed a strong variation in tick species composition among the study sites, linked in particular to the climate of the sites. We then analysed 791 ticks for DNA of vector-borne pathogens: Babesia/Theileria spp., Borrelia burgdorferi s.l., Anaplasma phagocytophilum, A. marginale, A. ovis, and Rickettsia of the spotted fever group (SFG). Theileria ovis was detected only in Corsica in Rh. bursa. Babesia venatorum (2 sites), Borrelia burgdorferi s.l. (B. afzelii and B. garinii; 2 sites) and Anaplasma phagocytophilum (3 sites) were detected in I. ricinus. Anaplasma ovis was detected at one site in I. ricinus and Rh. sanguineus s.l. SFG Rickettsia were detected at all the study sites: R. monacensis and R. helvetica in I. ricinus at the 3 sites where this tick is present; R. massiliae in Rh. sanguineus s.l. (1 site); and R. hoogstraalii and Candidatus R. barbariae in Rh. bursa in Corsica. These results show that there is a risk of tick-borne diseases for humans and domestic and wild animals frequenting these mountain areas.

Genotyping of ticks: first molecular report of Hyalomma asiaticum and molecular detection of tick-borne bacteria in ticks and blood from Khyber Pakhtunkhwa, Pakistan

Multiple ticks (Acari: Ixodoidea) carrying Rickettsiales bacteria have significant importance for both human and animal health. Thus, the purpose of this work was to genetically analyze tick species and their associated Rickettsiales bacteria in animal hosts. In order to achieve these objectives, various animals (including camels, cattle, goats, sheep, dogs, and mice) were inspected in four districts (Mardan, Peshawar, Kohat, and Karak) of Khyber Pakhtunkhwa to collect ticks, while blood samples were collected from all the symptomatic and asymptomatic cattle in all four districts. A total of 234 ticks were obtained from 86 out of 143 (60.14%) host animals, which were morphologically identified as Rhipicephalus turanicus, Rhipicephalus microplus, Haemaphysalis cornupunctata, and Hyalomma asiaticum. Among these, their representative ticks (126/234, 53.85%) were processed for molecular confirmation using cytochrome c oxidase (cox1) gene. Obtained cox1 sequences of four different tick species showed 99.72%-100% maximum identity with their corresponding species reported from Pakistan, China, India, and Kazakhstan and clustered phylogenetically. This study presented the first genetic report of Hy. asiaticum ticks in Pakistan. Moreover, genetically confirmed tick species were molecularly analyzed by PCR for detection of Rickettsiales DNA using partial fragments of 16S rDNA, 190-kDa outer membrane protein A (ompA), and 120-kDa outer membrane protein B (ompB) genes. In addition, blood samples were analyzed to identify Rickettsiales bacteria using the aforementioned genes. Rickettsiales bacteria were found in 24/126 (19.05%) ticks and 4/16 (25.00%) in symptomatic cattle's blood. The obtained ompA and ompB sequences from Hy. asiaticum ticks showed 99.73%-99.87% with Candidatus Rickettsia shennongii and unidentified Rickettsia sp., whereas the obtained 16S rDNA sequences from cattle's blood and ticks (Hae. cornupunctata) showed 99.67% highest identity with Anaplasma phagocytophilum. The 16S rDNA sequence of Rickettsiales DNA from Rh. turanicus ticks showed 100% identity with Ehrlichia canis and unidentified Ehrlichia sp. Obtained sequences of Rickettsiales bacteria were grouped along with their respective species in phylogenetic trees, which were previously reported in Greece, Cuba, Iraq, Turkey, Pakistan, South Korea, and China (mainland and Taiwan). This extensive study explores the wide range of damaging ticks and their corresponding tick-borne bacteria in the area, suggesting a possible danger to both livestock and human communities.

Molecular detection of Coxiella burnetii in ticks collected from Iran

The present study was conducted with the aim of investigating the prevalence and genetic structure of Coxiella burnetii in tick samples collected from domestic animals in Hormozgan province146 tick samples were randomly collected from cattle, sheep, goat, camel and dog herds in seven cities of Hormozgan. After the DNA was extracted from each tick sample; Nested-PCR method was used to identify the presence of C. burnetii using IS1111 transposon gene and isocitrate dehydrogenase icd gene. In addition, phylogenetic analysis and tree diagram were constructed based on IS1111 and icd genes. The results showed that out of 146 pool tick samples, 40 pool samples based on IS1111 gene and 32 pool samples based on icd gene were infected with C. burnetii. When results were stratified by livestock type, infection rates were highest in sheep ticks (37.5%, 95% CI: 21.2% - 57.29%), followed by cattle ticks (32.14%, 95% CI: 17.90% - 50.66%) and dog tick (15%, 95% CI: 70.6% - 29%). In camel and goat ticks, the infection rate was 15.90 and 23.07%, respectively. In conclusion, this study emphasizes the role of ticks as potential carriers of C. burneti. The results indicate the importance of cattle, sheep, goats, camels and dogs in Hormozgan region as effective factors in the epidemiology of Q fever and its impact on public health. In addition, a high degree of similarity (from 99% to 100%) was observed between IS1111 and icd genes in this study and recorded sequences from different regions of the world.

Comparison of ruminal microbiota, IL-1β gene variation, and tick incidence between Holstein × Gyr and Holstein heifers in grazing system

Introduction

The variation in bacterial communities among breeds has been previously reported and may be one of the reasons why Holstein × Gyr dairy heifers have better development in grazing systems in tropical conditions. This study aimed to explore the ruminal microbiota composition, the IL-1β gene variation, tick incidence, and blood parameters of Holstein × Gyr (½ Holstein × ½ Gyr) and Holstein heifers grazing intensely managed Guinea grass (Panicum maximum Jacq. cv. Mombaça).

Methods

Sixteen heifers were divided into two groups consisting of 8 Holstein × Gyr and 8 Holstein heifers. The experimental period was comprised of 3 periods of 21 days. Ruminal samples were taken via the stomach tube technique. The sequencing of the V4 hypervariable region of the 16S rRNA gene was performed using the Illumina MiSeq platform. Counting and collection of ticks were conducted each 21 days. Blood and skeletal muscle tissue biopsies were performed at the end of the experiment.

Results

Firmicutes were the most abundant phyla present in both breed rumen samples and Bacteroidota showed differences in relative abundance between breed groups, with greater values for Holstein heifers (p < 0.05 with FDR correction). The 10 most abundant unique OTUs identified in each breed included several OTUs of the genus Prevotella. Holstein heifers had a greater tick count and weight (9.8 ticks/animal and 1.6 g/animal, respectively) than Holstein × Gyr (2.56 ticks/animal and 0.4 g/animal, respectively). We found nucleotide substitutions in the IL-1β gene that might be related to adaptation and resistance phenotypes to tick infestation in Holstein × Gyr heifers. Blood concentrations of urea, albumin, insulin-like growth factor 1, triiodothyronine, and thyroxine were greater in Holstein × Gyr than in Holstein heifers.

Conclusion

Adaptations in Holstein × Gyr heifers such as ruminal microbiota, tick resistance, nucleotide substitutions in IL-1β gene, and hormone concentration suggest a better energy metabolism and thermoregulation resulting in better performance in tropical grazing systems.

THEILERIA EQUI INFECTION IN WORKING HORSES OF PAKISTAN: EPIDEMIOLOGY, MOLECULAR CHARACTERIZATION, AND HEMATOBIOCHEMICAL ANALYSIS

Theileria equi is 1 of the emerging and prevailing tick-borne hemoprotozoans adversely affecting the equids worldwide, including Pakistan. The current study aimed to investigate the prevalence and molecular characterization of T. equi in working horses (n = 194), the comparative efficacy of different diagnostic tests, associated risk factors, and hematobiochemical analysis. The blood samples of horses were subjected to microscopic examination, cELISA, and polymerase chain reaction (PCR) and the results revealed a prevalence of 9.79, 21.13, and 13.40%, respectively, for T. equi in working horses. The comparison of microscopy and cELISA results with PCR showed that cELISA had higher sensitivity (84.62%), but lower specificity (88.69%) and accuracy (88.14%) in comparison to microscopy (57.69, 97.62, and 92.27%). Molecular characterization of T. equi by phylogenetic analysis revealed a 61% resemblance of study isolates with each other OL662926, OL662925, and 82% similarity with isolate OL662924 while also showing homology with T. equi isolates of South Africa, South Korea, India, Pakistan, and Brazil. The risk factor analysis revealed a significant association (P < 0.05) of tick control status, previous tick history, tick infestation, house hygiene, deworming/vaccination, and the presence of other livestock species with T. equi infection in horses. The hematobiochemical profile revealed a significant (P < 0.05) decrease in red blood cells (RBCs), hemoglobin (Hb), packed cell volume (PCV), white blood cells (WBCs), platelet (PLT), phosphorus, and an increase in lymphocytes, granulocytes, aspartate aminotransferase (AST), glucose, bilirubin, blood urea nitrogen (BUN), and creatinine in T. equi-infected horses. The current study is the first comprehensive report for comparative evaluation of microscopy, cELISA, and PCR, assessment of epidemiological risk factors as well as hematobiochemical variations due to T. equi infection in Pakistan.

Isolation and electrophysiological recording of Ixodes ricinus synganglion neurons

The central nervous system of hard ticks (Ixodidae) consists of a concentrated merged nerve mass known as the synganglion. Although knowledge of tick neurobiology has dramatically improved over the last two decades, this is the first time that isolation and electrophysiological recordings have been carried out on tick neurons from the synganglion. Method: We developed a simple protocol for synganglion neuron isolation and used a whole-cell patch clamp to measure ionic currents induced by acetylcholine, nicotine and muscarine. Relatively large neurons (∼ 25 μm and ∼ 35 μm) were isolated and 1 mM acetylcholine was used to induce strong inward currents of -0.38 ± 0.1 nA and - 1.04 ± 0.1 nA, respectively, with the corresponding cell capacitances being at around 142 pF and 188 pF. In addition, successive application of 1 mM acetylcholine through ∼25 μm and ∼ 35 μm cells for increasing amounts of time resulted in a rapid reduction in current amplitudes. We also found that acetylcholine-evoked currents were associated with a reversible increase in intracellular calcium levels for each neuronal type. In contrast, 1 mM muscarine and nicotine induced a strong and non-reversible increase in intracellular calcium levels. This study serves as a proof of concept for the mechanical isolation of tick synganglion neurons followed by their electrophysiological recording. This approach will aid investigations into the pharmacological properties of tick neurons and provides the tools needed for the identification of drug-targeted sites and effective tick control measures.

Tick Species Diversity and Molecular Identification of Spotted Fever Group Rickettsiae Collected from Migratory Birds Arriving from Africa

The role of migratory birds in the spread of ticks and tick-borne pathogens along their routes from Africa to Europe is increasingly emerging. Wild birds can host several tick species, often infected by bacteria responsible for zoonoses. The aim of the study is to assess the possible introduction of exotic ticks carried by migratory birds into Italy from Africa and to detect the presence of Rickettsia species and Coxiella burnetii they may harbor. During a two-year survey, we collected ticks from migratory birds captured during their short stop-over on Ventotene Island. Specimens were first identified by morphology or sequencing molecular targets when needed, and then tested by real-time PCR for the presence of selected pathogens. A total of 91% of the collection consisted of sub-Saharan ticks, more than 50% of which were infected by Rickettsia species belonging to the spotted fever group, mainly represented by R. aeschlimannii. In contrast, the suspected C. burnetii detected in two soft ticks were confirmed as Coxiella-like endosymbionts and not the pathogen. Although there are still gaps in the knowledge of this dispersal process, our findings confirm the role of migratory birds in the spread of ticks and tick-borne pathogens, suggesting the need for a continuous surveillance to monitor the potential emergence of new diseases in Europe.

Molecular detection of Coxiella spp. in ticks (Ixodidae and Argasidae) infesting domestic and wild animals: with notes on the epidemiology of tick-borne Coxiella burnetii in Asia

Tick-borne Coxiella spp. are emerging in novel regions infecting different hosts, but information regarding their occurrence is limited. The purpose of this study was the molecular screening of Coxiella spp. in various ticks infesting goats, sheep, camels, cattle, wild mice, and domestic fowls (Gallus gallus domesticus) in various districts of Khyber Pakhtunkhwa, Pakistan. Morphologically identified tick species were confirmed by obtaining their cox1 sequences and were molecularly screened for Coxiella spp. by sequencing GroEL fragments. Almost 345 out of 678 (50.9%) hosts were infested by nine tick species. Regarding the age groups, the hosts having an age >3 years were highly infested (192/345, 55.6%), while gender-wise infestation was higher in female hosts (237/345, 68.7%). In collected ticks, the nymphs were outnumbered (613/1,119, 54.8%), followed by adult females (293/1,119, 26.2%) and males (213/1,119, 19.7%). A total of 227 ticks were processed for molecular identification and detection of Coxiella spp. The obtained cox1 sequences of nine tick species such as Hyalomma dromedarii, Hyalomma anatolicum, Haemaphysalis cornupunctata, Haemaphysalis bispinosa, Haemaphysalis danieli, Haemaphysalis montgomeryi, Rhipicephalus haemaphysaloides, Rhipicephalus microplus, and Argas persicus showed maximum identities between 99.6% and 100% with the same species and in the phylogenetic tree, clustered to the corresponding species. All the tick species except Ha. danieli and R. microplus were found positive for Coxiella spp. (40/227, 17.6%), including Coxiella burnetii (15/40, 6.7%), Coxiella endosymbionts (14/40, 6.3%), and different Coxiella spp. (11/40, 4.9%). By the BLAST results, the GroEL fragments of Coxiella spp. showed maximum identity to C. burnetii, Coxiella endosymbionts, and Coxiella sp., and phylogenetically clustered to the corresponding species. This is the first comprehensive report regarding the genetic characterization of Coxiella spp. in Pakistan's ticks infesting domestic and wild hosts. Proper surveillance and management measures should be undertaken to avoid health risks.

Multiomics Reveals Symbionts, Pathogens, and Tissue-Specific Microbiome of Blacklegged Ticks (Ixodes scapularis) from a Lyme Disease Hot Spot in Southeastern Ontario, Canada

Ticks in the family Ixodidae are important vectors of zoonoses, including Lyme disease (LD), which is caused by spirochete bacteria from the Borreliella (Borrelia) burgdorferi sensu lato complex. The blacklegged tick (Ixodes scapularis) continues to expand across Canada, creating hot spots of elevated LD risk at the leading edge of its expanding range. Current efforts to understand the risk of pathogen transmission associated with I. scapularis in Canada focus primarily on targeted screens, while natural variation in the tick microbiome remains poorly understood. Using multiomics consisting of 16S metabarcoding and ribosome-depleted, whole-shotgun RNA transcriptome sequencing, we examined the microbial communities associated with adult I. scapularis (n = 32), sampled from four tissue types (whole tick, salivary glands, midgut, and viscera) and three geographical locations within a LD hot spot near Kingston, Ontario, Canada. The communities consisted of both endosymbiotic and known or potentially pathogenic microbes, including RNA viruses, bacteria, and a Babesia sp. intracellular parasite. We show that β-diversity is significantly higher between the bacterial communities of individual tick salivary glands and midguts than that of whole ticks. Linear discriminant analysis effect size (LEfSe) determined that the three potentially pathogenic bacteria detected by V4 16S rRNA sequencing also differed among dissected tissues only, including a Borrelia strain from the B. burgdorferi sensu lato complex, Borrelia miyamotoi, and Anaplasma phagocytophilum. Importantly, we find coinfection of I. scapularis by multiple microbes, in contrast to diagnostic protocols for LD, which typically focus on infection from a single pathogen of interest (B. burgdorferi sensu stricto). IMPORTANCE As a vector of human health concern, blacklegged ticks (Ixodes scapularis) transmit pathogens that cause tick-borne diseases (TBDs), including Lyme disease (LD). Several hot spots of elevated LD risk have emerged across Canada as I. scapularis expands its range. Focusing on a hot spot in southeastern Ontario, we used high-throughput sequencing to characterize the microbiome of whole ticks and dissected salivary glands and midguts. Compared with whole ticks, salivary glands and midguts were more diverse and associated with distinct bacterial communities that are less dominated by Rickettsia endosymbiont bacteria and are enriched for pathogenic bacteria, including a B. burgdorferi sensu lato-associated Borrelia sp., Borrelia miyamotoi, and Anaplasma phagocytophilum. We also found evidence of coinfection of I. scapularis by multiple pathogens. Overall, our study highlights the challenges and opportunities associated with the surveillance of the microbiome of I. scapularis for pathogen detection using metabarcoding and metatranscriptome approaches.

The emergence of the Biodiversity/Health nexus: making biodiversity a health issue

Before the COVID-19 pandemic, a French epistemic community has forged and promoted a Biodiversity/Health nexus, which legitimizes biodiversity as a health issue. The relationship between biodiversity and health is now part of French local government agendas, after being included in new international programs. Based on observation of this nexus’s epistemic community and 35 semi-structured interviews conducted in France between 2017 and 2020, this article aims to show which actors and groups have been forging and promoting this nexus, and to understand how such an emergent environmental nexus challenges the governance of the present biomedical- and technical expertise-based health system. This article discusses environmental nexus from the perspective of building a new cause by reconstituting chains of causality to “demonstrate” the new problem (Barthe, Politix, 23(91), 77–102, 2010), and the growing importance of integration of concepts as a new ideal of policy-making (Cairns & Krzywoszynska, Environmental Science and Policy, 64, 164–170, 2016). As well as a justification (Boltanski & Thevenot, 1991) of their effectiveness in legitimizing the cause of defending biodiversity, environmental nexuses contain a challenge to recognize knowledge, calling for a change in governance methods in a One Health approach.

Perceived vulnerability for Lyme disease questionnaire: A social science tool for understanding tick-borne disease attitudes

Lyme disease has emerged as a growing epidemic across the U.S., with tick populations spreading north because of a plethora of human-induced factors. As the scope of this problem grows, there is a need to understand how vulnerable the public perceives themselves to be and how perceived vulnerability as a psychological construct influences public behavior. A growing body of literature has explored individual risk perceptions and individual preventative behaviors toward Lyme disease, but there remains a notable research gap regarding the concept of vulnerability. This empirical study establishes the first questionnaire for perceived vulnerability towards Lyme disease, modified from pre-existing infectious disease literature. This novel instrument was tested and compared with individual factors relating to preventative behaviors and source credibility of major information sources about Lyme disease in the state of Maine. Recent increases in black-legged tick (Ixodes scapularis) populations have affected the state of Maine in dramatic ways. This research specifically surveyed homeowners to explore their perceived vulnerability, source credibility, and individual protective intentions related to ticks and Lyme disease in Maine. Results from this study validate a modified perceived vulnerability scale for Lyme disease and highlight how understanding the relationships between these perceptions of vulnerability, individual behaviors, and sources of information can improve outreach and communication efforts about tick-borne diseases.

Molecular survey of Anaplasma and Ehrlichia species in livestock ticks from Kassena-Nankana, Ghana; with a first report of Anaplasma capra and Ehrlichia minasensis

Tick-borne pathogens harm livestock production and pose a significant risk to public health. To combat these effects, it is necessary to identify the circulating pathogens to create effective control measures. This study identified Anaplasma and Ehrlichia species in ticks collected from livestock in the Kassena-Nankana Districts between February 2020 and December 2020. A total of 1550 ticks were collected from cattle, sheep and goats. The ticks were morphologically identified, pooled and screened for pathogens using primers that amplify a 345 bp fragment of the 16SrRNA gene and Sanger sequencing. The predominant tick species collected was Amblyomma variegatum (62.98%). From the 491 tick pools screened, 34 (6.92%) were positive for Ehrlichia and Anaplasma. The pathogens identified were Ehrlichia canis (4.28%), Ehrlichia minasensis (1.63%), Anaplasma capra (0.81%) and Anaplasma marginale (0.20%). This study reports the first molecular identification of the above-mentioned Ehrlichia and Anaplasma species in ticks from Ghana. With the association of human infections with the zoonotic pathogen A. capra, livestock owners are at risk of infections, calling for the development of effective control measures.

Importance of Host Abundance and Microhabitat in Tick Abundance

To reduce the risk of zoonoses, it is necessary to understand the infection process, including the ecology of animals and vectors (i.e., the 'One Health' approach). In temperate climates, ticks are the major vectors of zoonoses, so factors determining their abundance, such as host mammal abundance and microhabitat conditions, should be clarified. Sika deer (Cervus nippon) are a major tick host and are rapidly expanding their distribution in Japan. We established 12 plots along a gradient of sika deer abundance in Tochigi Prefecture, Japan. We monitored the occurrence of mammal species with camera traps and sampled questing ticks on a monthly basis by flagging along three transects (center of a trail, forest edge, and forest interior) at each site from April to November 2018. The camera traps recorded 12 mammal species, predominantly sika deer. Five Haemaphysalis species and three Ixodes species were sampled. The numbers of ticks sampled were explained by the photographic frequency of sika deer, and partly by that of other mammal species, depending on tick species and their developmental stages. The numbers of sampled adult and nymphal ticks were the highest at the forest edge, where vegetation cover was greatest. Thus, vegetation management in tick habitats and the control of sika deer populations may reduce tick abundance.

Transmission Cycle of Tick-Borne Infections and Co-Infections, Animal Models and Diseases

Tick-borne pathogens such as species of Borrelia, Babesia, Anaplasma, Rickettsia, and Ehrlichia are widespread in the United States and Europe among wildlife, in passerines as well as in domestic and farm animals. Transmission of these pathogens occurs by infected ticks during their blood meal, carnivorism, and through animal bites in wildlife, whereas humans can become infected either by an infected tick bite, through blood transfusion and in some cases, congenitally. The reservoir hosts play an important role in maintaining pathogens in nature and facilitate transmission of individual pathogens or of multiple pathogens simultaneously to humans through ticks. Tick-borne co-infections were first reported in the 1980s in white-footed mice, the most prominent reservoir host for causative organisms in the United States, and they are becoming a major concern for public health now. Various animal infection models have been used extensively to better understand pathogenesis of tick-borne pathogens and to reveal the interaction among pathogens co-existing in the same host. In this review, we focus on the prevalence of these pathogens in different reservoir hosts, animal models used to investigate their pathogenesis and host responses they trigger to understand diseases in humans. We also documented the prevalence of these pathogens as correlating with the infected ticks’ surveillance studies. The association of tick-borne co-infections with other topics such as pathogens virulence factors, host immune responses as they relate to diseases severity, identification of vaccine candidates, and disease economic impact are also briefly addressed here.

Long-term sex-dependent inflammatory response of adult frogs to ammonium exposure during the larval stage

Among others, the global change involves a worldwide increase in cropland area, with the concomitant rise in nitrogenous fertilizer supplementation and species range alterations, including parasites and pathogens. As most animals rely on their immune systems against these infectious agents, studying the potential effects of nitrogenous compounds on animal immune response is vital to understand their susceptibility to infections under these altered circumstances. Being subjected to an alarming process of global declines, amphibians are the object of particular attention, given their sensitivity to these compounds, especially to ammonium. Moreover, whereas adults can actively avoid polluted patches, larvae are confined within their waterbodies, thus exposed to contaminants in it. In this work, we test whether chronic exposure to a sublethal dose of ammonium during the larval stage of Pelophylax perezi frogs, released from all contamination after metamorphosis, leads to impaired inflammatory response to phytohemagglutinin in adults. We also test whether such a response differs between agrosystem individuals as compared with conspecifics from natural habitats. We found negative carryover effects of chronic exposure of larvae to ammonium on adult inflammatory response, which could imply a greater susceptibility to pathogens and parasites. However, this damage is only true for males, which, according to the immunocompetence handicap hypothesis, could be a consequence of a testosterone-triggered impairment of male immune function. In disagreement with our prediction, however, we detected no differences in the inflammatory response of agrosystem frogs to phytohemagglutinin as compared with natural habitat conspecifics.

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

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.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05425-1.

American dog ticks along their expanding range edge in Ontario, Canada

The American dog tick, Dermacentorvariabilis, is a tick of public and veterinary health importance in North America. Using passive tick surveillance data, we document distribution changes for the American dog tick in Ontario, Canada, from 2010 through 2018. Dermacentorvariabilis submissions from the public were geocoded and aggregated—from large to small administrative geographies—by health region, public health unit (PHU) and Forward Sortation Area (FSA). PHU hot spots with high rates of D. variabilis submissions were (1) Brant County, Haldimand-Norfolk and Niagara Regional in the Central West region and (2) Lambton and Winsor-Essex County in the South West region. The number of established D. variabilis populations with ≥ 6 submissions per year increased significantly during the study at regional (PHUs: 22 to 31) and local (FSAs: 27 to 91) scales. The range of D. variabilis increased similarly to the positive control (Ixodesscapularis) during the study and in contrast to the static range of the negative control (Ixodescookei). Submission hot spots were in warmer, low elevation areas with poorly drained soils, compared to the province’s low submission areas. Dermacentorvariabilis is spreading in Ontario and continued research into their vector ecology is required to assess medicoveterinary health risks.

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

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

Molecular assessment of Theileria equi and Babesia caballi prevalence in horses and ticks on horses in southeastern France

Equine piroplasmosis (EP) is a tick-borne disease caused by Babesia caballi and Theileria equi that is potentially emerging in non-endemic countries. We conducted a descriptive study to investigate EP prevalence and spatial distribution in an endemic region: the Camargue and the Plain of La Crau in France. In spring 2015 and 2016, we carried out sampling at stables (total n = 46) with a history of horses presenting chronic fever or weight loss. Overall, we collected blood from 632 horses, which were also inspected for ticks; these horses had been housed in the target stables for at least 1 year. We obtained 585 ticks from these horses and described land use around the stables. Real-time PCR was employed to assess T. equi and B. caballi prevalence in the horses and in the ticks found on the horses. For the horses, T. equi and B. caballi prevalence was 68.6% and 6.3%, respectively. For the ticks found on the horses, prevalence was 28.8% for T. equi and 0.85% for B. caballi. The most common tick species were, in order of frequency, Rhipicephalus bursa, R. sanguineus sl., Hyalomma marginatum, Haemaphysalis punctata, and Dermacentor sp. Horses bearing Rhipicephalus ticks occurred in wetter zones, closer to agricultural areas, permanent crops, and ditches, as well as in drier zones, in the more northern countryside. Compared to horses bearing R. bursa, horses bearing R. sanguineus sl. more frequently occurred near the Rhone River. Prevalence of T. equi in the ticks was as follows: Hyalomma marginatum (43%), Dermacentor sp. (40%), R. bursa (33%), R. sanguineus sl. (19%), and Haemaphysalis punctata (17%). In contrast, B. caballi only occurred in Dermacentor sp. (20%) and R. bursa (1%).

Borrelia burgdorferi and Borrelia miyamotoi in Atlantic Canadian wildlife

Borrelia burgdorferi and Borrelia miyamotoi are tick-vectored zoonotic pathogens maintained in wildlife species. Tick populations are establishing in new areas globally in response to climate change and other factors. New Brunswick is a Canadian maritime province at the advancing front of tick population establishment and has seen increasing numbers of ticks carrying B. burgdorferi, and more recently B. miyamotoi. Further, it is part of a region of Atlantic Canada with wildlife species composition differing from much of continental North America and little information exists as to the presence and frequency of infection of Borrelia spp. in wildlife in this region. We used a citizen science approach to collect a wide range of animals including migratory birds, medium-sized mammals, and small mammals. In total we tested 339 animals representing 20 species for the presence of B. burgdorferi and B. miyamotoi. We have developed new nested PCR primers and a protocol with excellent specificity for detecting both of these Borrelia species, both single and double infections, in tissues and organs of various wildlife species. The positive animals were primarily small non-migratory mammals, approximately twice as many were infected with B. burgdorferi than B. miyamotoi and one animal was found infected with both. In addition to established reservoir species, the jumping mouse (Napaeozapus insignis) was found frequently infected; this species had the highest infection prevalence for both B. burgdorferi and B. miyamotoi and has not previously been identified as an important carrier for either Borrelia species. Comprehensive testing of tissues found that all instances of B. burgdorferi infection were limited to one tissue within the host, whereas two of the five B. miyamotoi infections were diffuse and found in multiple systems. In the one coinfected specimen, two fetuses were also recovered and found infected with B. miyamotoi. This presumptive transplacental transmission suggests that vertical transmission in mammals is possible. This finding implies that B. miyamotoi could rapidly spread into wildlife populations, as well as having potential human health implications.

Detection of Babesia spp. in High Altitude Cattle in Ecuador, Possible Evidence of the Adaptation of Vectors and Diseases to New Climatic Conditions

Background: Babesia species are intraerythrocytic protozoa, distributed in tropical and subtropical areas of the world, causing anemic diseases in many animals, including cattle. This disease, called babesisosis, is transmitted from one animal to another through ticks (Tick Borne-Disease or TBD). On the other hand, Ecuador has a tropical climate that allows the development of the vector Rhipicephalus microplus, and therefore favors the transmission of Babesia spp. in cattle. Methods and principal findings: We determined the presence of Babesia spp. by PCR using 18s ribosomal gene as target (18s PCR) in 20 farms in the area of El Carmen (zone below 300 m above sea level) and 1 farm in Quito (2469 m.a.s.l.). In addition, we analyzed parameters such as age, sex, and packed cell volume (PCV) as explanatory variable associated with the disease. Results: The 18s PCR test showed that 18.94% (14.77% Babesia bovis and 4.17% Babesia bigemina) and 20.28% (14.69% B. bovis and 5.59% B. bigemina) of the cattle were positive for Babesia spp in farms sampled in El Carmen and in Quito, respectively. Age influenced the presence of animals positive for Babesia spp., but sex and PCV did not. The phylogenetic analysis of sequences showed 4 isolates of B. bovis and 3 isolates of B. bigemina in the 2 study zones, with similarities between 99.73 and 100% with other sequences. One B. bovis isolate was similar in the zone of El Carmen and Quito. Conclusion and significance: This work is the first molecular characterization of B. bigemina and B. bovis in Ecuador, and it is also the first evidence of Babesia spp. in cattle in the area of Quito at an altitude of 2469 m.a.s.l., being the highest altitude reported for animals with babesiosis and for the tick R. microplus. Climatic factors as well as mobility of tick-carrying animals without any control allow the presence of Babesiosis outbreaks in new geographical areas.

First report regarding molecular epidemiology and novel variant identification of Anaplasma centrale in cattle from Pakistan

Anaplasma centrale (A. centrale) is an obligate red blood cell residing tick transmitted rickettsiae that has not been studied extensively for its prevalence in cattle along with its epidemiology. Aim of this investigation was to report the seasonal prevalence, phylogeny and epidemiological parameters associated with the prevalence of A. centrale in cattle breeds enrolled from District Layyah in Punjab, Pakistan. A total of 844 blood samples [Cross breed = 300, Holstein Friesian = 244, Sahiwal breed = 300)] were collected from apparently healthy cattle along with epidemiological data during 2017-18. PCR amplified 426 base pair fragment from 16S rRNA gene of A. centrale in 14.4% (122/844) of cattle. Amplified 16S rRNA partial gene sequence of A. centrale were confirmed by DNA sequencing and deposited to GenBank. Highest A. centrale prevalence was observed in spring (24%) followed by autumn (12.4%) summer (10%) and winter (7.1%) seasons. Sahiwal breed (18.3%) was most susceptible to A. centrale infection followed by cross (12.3%) and Holstein Friesian breed (12.3%). 69/844 (8.2%) of Giemsa stained cattle blood smears were also found positive for Anaplasma spp. Farms where animal use to drink pool water and farms where dogs and other dairy animals were living with cattle had higher A. centrale prevalence. Female cattle and dogs having tick burden were found associated with A. centrale infection. Hematological profile was severely disturbed in A. centrale positive cattle. It is recommended that A. centrale should be screened in cattle, in addition to A. marginale, for the effective control of tick born diseases in Pakistan.

A mammal tick with a taste for lizard blood: Parasitism by the kangaroo soft tick, (Ornithodoros gurneyi) on sleepy lizards (Tiliqua rugosa)

The kangaroo soft tick (Ornithodoros gurneyi) inhabits xeric habitats of Australia and, as a result, little is known about the natural hosts of the different life stages of this tick. Large macropods are inferred as the kangaroo soft tick's principal hosts since all life stages inhabit the loose soil of kangaroo wallows. These ticks have been reported to parasitize bearded dragons (Pogona barbata) and sleepy lizards (Tiliqua rugosa), however it is not known whether these lizards are competent hosts of this tick. In this study the prevalence and intensity of O. gurneyi parasitism on T. rugosa was examined by sampling lizards at a long-term study site spanning a precipitation-induced ecological gradient. The competence of T. rugosa as a host for O. gurneyi was explored by keeping larvae and nymphs of O. gurneyi, that had fed on T. rugosa, in captivity to determine if they will survive and moult. We found that O. gurneyi occurs throughout the study site, but that they were seldom recorded to parasitise T. rugosa. Still, it was noted that T. rugosa is a competent host of O. gurneyi. The results of this study indicate that kangaroos are not the only competent hosts of O. gurneyi and raises the question of whether T. rugosa and other lizards may play a role in the dispersal of these ticks.

Prevalence of Risk and Protective Factors for Tick Exposure and Tick-Borne Disease Among Residents of Indiana

OBJECTIVE

To determine the prevalence of risk and protective factors for tick exposure and tick-borne disease (TBD) based on gender and living in urban or rural areas (urbanicity) among a cross section of Indiana adults.

METHODS

Data were collected from 3003 adults (81% response rate) spread across all 92 Indiana counties. Study participants were recruited from existing online panels maintained by Qualtrics. We calculated prevalence ratio (PR) and 95% confidence interval (CI) of 8 primary outcomes for 2 different exposures: (1) gender (male/female) and (2) urbanicity.

RESULTS

Female participants were 10% less likely to find a tick on themselves than male participants (PR = 0.90; 95% CI, 0.74-0.99) and significantly more likely to worry about their health and safety because of ticks, whereas males avoided the outdoors less because of worry about ticks. Female participants were significantly more likely to adopt various personal protective measures, specifically because of concern for ticks. Female participants were also less likely to have been told by a health care provider that they have a TBD (PR = 0.53; 95% CI, 0.38-0.75). Rural participants were significantly more likely to report seeing a tick at their residential property (PR = 2.40; 95% CI, 2.11-2.76), report finding ticks on themselves (PR = 1.90; 95% CI, 1.68-2.23), and report finding a tick on a child at their residential property within the past 6 months than urban dwellers (PR = 1.37; 95% CI, 1.06-1.77). In addition, we found that 62% of participants have very high trust in government sources of information on TBD and tick prevention.

CONCLUSIONS

In Indiana, the area around people's residences may constitute an important source of tick exposure for humans. Being exposed to ticks is most prevalent in those living in rural areas of Indiana. Finally, risk factors for TBD are higher among males than among females.

First hemispheric report of invasive tick species Haemaphysalis punctata, first state report of Haemaphysalis longicornis, and range expansion of native tick species in Rhode Island, USA

BACKGROUND

Invasive arthropod vectors and the range expansions of native vectors can lead to public and veterinary health concerns, as these vectors may introduce novel pathogens or spread endemic pathogens to new locations. Recent tick invasions and range expansion in the USA has been attributed to climate and land use change, an increase in global travel, and importations of exotic animals.

METHODS

A 10-year surveillance study was conducted on Block Island, Rhode Island, from 2010 to 2020 including sampling ticks from small mammal and avian hosts.

RESULTS

We report the discovery and establishment of the red sheep tick (Haemaphysalis punctata) for the first time in the western hemisphere and in the US. This invasive species was first collected in 2010 on Block Island, was collected continuously throughout the study, and was collected from an avian host. We document the first report of the invasive Asian longhorned tick (Haemaphysalis longicornis) in the state of Rhode Island, first observed at our sites in 2018. Finally, we present data on the range expansion and establishment of two native tick species, the lone star tick and the rabbit tick, on Block Island.

CONCLUSION

This study emphasized the importance of long-term surveillance to detect changes in tick host communities, including invasive and expanding native vectors of potential significance to humans and wildlife.

Risk factors associated with tick infestations on equids in Khyber Pakhtunkhwa, Pakistan, with notes on Rickettsia massiliae detection

BACKGROUND

Studies on ticks infesting equids are lacking in various parts of the world, including Khyber Pakhtunkhwa (KP), Pakistan. The aim of this study was to investigate the diversity of ticks infesting equids, associated risk factors and rickettsial detection in ticks from equids in KP.

METHODS

Inspection of 404 equid hosts from November 2018 to October 2019 resulted in the collection of 550 ticks. Data on tick-associated risk factors were collected from equid owners by means of a questionnaire. After morphological identification, partial DNA sequences of the tick mitochondrial 16S rRNA gene were used for taxonomic confirmation of species. Partial sequences of the gltA and ompA genes were used for Rickettsia detection in ticks.

RESULTS

A total of 550 tick specimens were collected on 324 (80.2%) of the equids inspected, of which 161 were horses (50%), 145 (45%) were donkeys and 18 were mules (5%). The ticks were identified as belonging to the following five species: Rhipicephalus microplus (341 specimens, 62% of the total ticks), Rh. haemaphysaloides (126, 23%), Rh. turanicus (39, 7%), Rh. sanguineus (s.l.) (33, 6%) and Hyalomma anatolicum (11, 2%). The most prevalent tick life stage was adult females (279, 51%) followed by adult males (186, 34%) and nymphs (85, 15%). Higher tick infestations were observed on male equids (relative risk [RR] 0.7432, P < 0.0005) and adult equids (RR 1.268, P < 0.0020). Ticks were frequently attached to the axial region of horses (55, 21%), sternum of donkeys (44, 21%) and belly of mules (19, 23%) (P < 0.04). Temporal patterns of tick infestation in association with temperature and humidity were highly significant (P < 0.05). Risk factors, such as animal housing (P < 0.0003), living management (P < 0.006), grazing type (P < 0.01) and location in hilly areas (P < 0.02), significantly enhanced the chances for tick infestation. Tick species analyzed in this study were phylogenetically related to species from Afghanistan, China, South Africa and Taiwan. Partial sequences of the gltA and ompA genes obtained from Rh. microplus and Rh. haemaphysaloides were 100% identical to the spotted fever group pathogen Rickettsia massiliae.

CONCLUSIONS

Equids exposed to significant risk factors were infected by one or more of at least five tick species in KP, Pakistan, and some of the ticks harbored the human pathogen R. massiliae.

Molecular detection and phylogenetic analyses of Anaplasma spp. in Haemaphysalis longicornis from goats in four provinces of China

Anaplasma species, which are distributed worldwide, are gram-negative obligate intracellular tick-borne bacteria that pose a threat to human and animal health. Haemaphysalis longicornis ticks play a vital role as vectors in the transmission of Anaplasma pathogens. However, the Anaplasma species carried by H. longicornis in China are yet to be characterized. In this study, 1074 H. longicornis specimens were collected from goats in four provinces of China from 2018 to 2019 and divided into 371 sample pools. All tick sample pools were examined for the presence of Anaplasma species via nested PCR amplification of 16S ribosomal RNA, major surface protein 4 (msp4), or citric acid synthase (gltA) genes, which were sequenced to determine the molecular and phylogenetic characteristics of the isolates. The overall Anaplasma spp-positive rate of H. longicornis was determined to be 26.68% (99/371). The percentage prevalence of A. phagocytophilum-like1, A. bovis, A. ovis, A. marginale, and A. capra were 1.08% (4/371), 13.21% (49/371), 13.21% (49/371), 1.35% (5/371), and 10.24% (38/371), respectively, and the co-infection rate of two or more types of Anaplasma was 6.47% (24/371). Phylogenetic analyses led to the classification of A. phagocytophilum into an A. phagocytophilum-like1 (Anaplasma sp. Japan) group. Anaplasma bovis sequences obtained in this study were 99.8–100% identical to those of an earlier strain isolated from a Chinese tick (GenBank accession no. KP314251). Anaplasma ovis sequences showed 99.3–99.6% identity to an A. ovis human strain identified from a Cypriot patient (GenBank accession no. FJ460443). Only one msp4 sequence of A. marginale was detected and was grouped with those of other A. marginale isolates, and these A. capra isolates obtained in this present study may be zoonotic. The detection and characterization of four Anaplasma species in H. longicornis in this study have added to the current knowledge of the parasite and provided data on multiple Anaplasma species with veterinary and medical significance from four provinces of China.

Long-term study of Borrelia and Babesia prevalence and co-infection in Ixodes ricinus and Dermacentor recticulatus ticks removed from humans in Poland, 2016-2019

Background

Lyme borreliosis (LB) is the most common vector-borne disease in Europe. Monitoring changes in the prevalence of different Borrelia species in ticks may be an important indicator of risk assessment and of differences in pathogenicity in humans. The objective of our study was to assess the prevalence, co-infection and distribution of Borrelia and Babesia species in ticks removed from humans in a large sample collected during a study period of 4 years.

Methods

The ticks were collected throughout Poland from March to November over 4-year period from 2016 to 2019. All ticks (n = 1953) were morphologically identified in terms of species and developmental stage. Molecular screening for Borrelia and Babesia by amplification of the flagellin gene (flaB) or 18S rRNA marker was performed. Pathogen identity was confirmed by Sanger sequencing or PCR–restriction fragment length polymorphism analysis.

Results

The ticks removed from humans in Poland during this study belonged to two species: Ixodes ricinus (97%) and Dermacentor reticulatus (3%). High Borrelia prevalence (25.3%), including B. miyamotoi (8.4%), was confirmed in Ixodes ricinus ticks removed from humans, as was the change in frequency of occurrence of Borrelia species during the 4-year study. Despite Babesia prevalence being relatively low (1.3%), the majority of tested isolates are considered to be pathogenic to humans. Babesia infection was observed more frequently among Borrelia-positive ticks (2.7%) than among ticks uninfected with Borrelia (0.8%). The most frequent dual co-infections were between Borrelia afzelii and Babesia microti. The presence of Borrelia was also confirmed in D. reticulatus (12.7%); however the role of these ticks in spirochete transmission to susceptible hosts is still unclear.

Conclusions

Although the overall risk of developing LB after a tick bite is low in Europe, knowledge of the prevalence and distribution of Borrelia and Babesia species in ticks might be an important indicator of the risk of both these tick-borne diseases.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-021-04849-5.

Life Cycle and Genetic Identification of Argas persicus Infesting Domestic Fowl in Khyber Pakhtunkhwa, Pakistan

Ticks transmit numerous pathogens to animals including humans; therefore, they are parasites of health concern. Soft ticks infesting domestic fowl in Pakistan are carriers of viruses and bacteria and cause unestimated economic losses in the poultry sector. The current study was intended to identify soft ticks infesting domestic fowl and understand their spatiotemporal distribution along 1 year. A sum of 7,219 soft ticks were collected from 608 domestic fowl in 58 infested shelters; 938 (12.9%) ticks were found on the host and 6,281 (87%) in the shelters. The collected ticks comprised 3,503 (48.52%) adults including 1,547 (21.42%) males and 1,956 (27.09%) females, 3,238 (44.85%) nymphs, and 478 (6.62%) larvae. The most prevalent life stages were adults, followed by nymphs and larvae. Overall tick prevalence considering all visited shelters was 38.66% (58/150). The highest tick prevalence was found in district Lakki Marwat (50.03%) followed by Peshawar (31.08%) and Chitral (18.88%) districts. All ticks were morpho-taxonomically identified as Argas persicus. To determine their life cycle, adult A. persicus were reared in the laboratory infesting domestic fowl (Gallus gallus domesticus). The life cycle was completed in 113–132 days (egg to egg) with a mean temperature of 33 ± 3°C and relative humidity of 65 ± 5%. Individual ticks were used for DNA extraction and subjected to polymerase chain reaction (PCR) using specific primers for the amplification of a partial fragment of mitochondrial cytochrome oxidase subunit I (cox1) and 16S ribosomal RNA (16S rRNA) genes. Obtained amplicons were compared using basic local alignment search tool (BLAST) to scan for homologous sequences. Phylogenetic trees showed A. persicus from Pakistan clustering with conspecific sequences reported from Australia, Chile, China, Kenya, and the United States. This is the first study aiming to reproduce the life cycle of A. persicus and genetically identify this tick in the region. Further studies are encouraged to investigate the pathogens associated with this soft tick species in Pakistan.

Abundance of Ticks (Acari: Ixodidae) and Presence of Rickettsia and Anaplasma in Ticks Infesting Domestic Animals From Northern India

Rickettsia and Anaplasma are bacteria that can be transmitted by hematophagous arthropods such as ticks infesting animals in close proximity to humans. The main objective of the present study was to investigate abundance of common tick species infesting domestic animals and presence of Rickettsia and Anaplasma in tick populations. Adult ticks were collected from domestic animals in rural areas and screened by molecular detection of bacterial DNA for these two genera of bacteria. A total of 1,778 adult ixodid tick specimens were collected from 200 cattle, 200 buffaloes, 200 goats, and 40 dogs. The collection consisted of four species of ixodid ticks, Rhipicephalus (Boophilus) microplus (Canestrini) (83.8%), Hyalomma kumari (Sharif) (7.1%), Rhipicephalus sanguineus (Latreille) (6.4%), and Dermacentor auratus (Supino) (2.7%) infesting the domestic animals. The prevalence of all the collected tick species was highest in the month of October. Anaplasma spp. was the most frequently identified bacteria (3.3%) in tested ticks. Of 17 positive tick pools for Anaplasma spp., 14 pools were from ticks infesting cattle, 2 pools of ticks collected from buffalo, and the remaining pool were ticks infesting a goat at the time of collection. Although 1.6% tick pools of R. microplus collected from cattle tested positive for Rickettsia spp., present investigation provides evidence of the most prevalent ixodid ticks infesting domestic animals and the presence of obligate intracellular bacteria, Rickettsia and Anaplasma, in these ticks collected in the Gorakhpur division of Northern India.

Efficacy of a novel topical combination of esafoxolaner, eprinomectin and praziquantel against Ixodes ricinus and Ixodes scapularis in cats

Esafoxolaner is a purified enantiomer of afoxolaner with insecticidal and acaricidal properties. It is combined with eprinomectin and praziquantel in a novel topical endectoparasiticide formulation for cats. The efficacy of this novel formulation was evaluated in three Ixodes ricinus and two Ixodes scapularis experimental studies, with comparable designs. In each study, cats were randomly allocated, based on a pre-treatment tick infestation and count, to a placebo control group or a group treated with the minimum recommended dose of the novel formulation. Cats were infested two days before treatment and weekly thereafter. Immediate efficacy was evaluated 48 h after treatment; persistent efficacy was evaluated 48 h after new weekly infestations for at least one month after the treatment (in one of the studies, the first two weeks of persistent efficacy against I. ricinus were not tested). Efficacy was calculated at each timepoint by comparison of arithmetic means of live ticks found in the control and the treated groups. In the three studies targeting I. ricinus, immediate and persistent efficacies ranged between 91% and 100% for five weeks. In the two studies targeting I. scapularis, immediate and persistent efficacies ranged between 95% and 100%, and 98% and 100% for one month, respectively. These studies provide robust evidence of efficacy of the novel topical formulation of esafoxolaner, eprinomectin and praziquantel against experimental I. ricinus and I. scapularis infestations for at least one month in cats.

Ticks and Tick-Borne Diseases of Colorado, Including New State Records for Argas radiatus (Ixodida: Argasidae) and Ixodes brunneus (Ixodida: Ixodidae)

We report 28 species of ticks (Acari: Ixodida) from Colorado (CO). We include the soft ticks (Argasidae) Argas (Argas) cooleyi Kohls and Hoogstraal, Argas (Persicargas) radiatus Railliet, Carios (Alectorobius) concanensis (Cooley and Kohls), Carios (Alectorobius) kelleyi (Cooley and Kohls), Ornithodoros (Pavlovskyella) hermsi Wheeler et al., Ornithodoros (Pavlovskyella) parkeri Cooley, Ornithodoros (Pavlovskyella) turicata (Dugès), Otobius (Otobius) lagophilus Cooley and Kohls, and Otobius (Otobius) megnini (Dugès). We include the metastriate hard ticks (Ixodidae) Dermacentor (Americentor) albipictus (Packard), Dermacentor (Dermacentor) andersoni Stiles, Dermacentor (Dermacentor) parumapertus Neumann, Dermacentor (Dermacentor) variabilis (Say), Haemaphysalis (Aboimisalis) chordeilis (Packard), Haemaphysalis (Gonixodes) leporispalustris (Packard), and Rhipicephalus (Rhipicephalus) sanguineus Latreille. Prostriate hard ticks include Ixodes (Ixodiopsis) angustus Neumann, Ixodes (Phoeloioxdes) baergi Cooley and Kohls, Ixodes (Trichotoixodes) brunneus Koch, Ixodes (Scaphixodes) howelli Cooley and Kohls, Ixodes (Phoeloioxdes) kingi Bishopp, Ixodes (Phoeloioxdes) marmotae Cooley and Kohls, Ixodes (Ixodiopsis) ochotonae Gregson, Ixodes (Phoeloioxdes) sculptus Neumann, Ixodes (Ixodiopsis) soricis Gregson, Ixodes (Ixodes) spinipalpis Hadwen and Nuttall, Ixodes (Phoeloioxdes) texanus Banks, and Ixodes (Ixodiopsis) woodi Bishopp. Argas radiatus and Ixodes brunneus represent new state records. Review of collection reports revealed that inclusion of Ixodes (Multidentatus) auritulus (Neumann), Ixodes (Phoeloioxdes) cookei Packard, Ixodes (Phoeloioxdes) marxi Banks, and Ixodes (Ixodes) pacificus Cooley and Kohls is dubious or unconfirmed and, conversely, that C. concanensis and H. chordeilis have distributions that include CO. We list an additional five species occasionally detected and 13 exotic species intercepted in CO. Tick-host associations, geographical distributions, and medical/veterinary importance are included.

Behavioral characteristics and endosymbionts of two potential tularemia and Rocky Mountain spotted fever tick vectors

Due to climate change-induced alterations of temperature and humidity, the distribution of pathogen-carrying organisms such as ticks may shift. Tick survival is often limited by environmental factors such as dryness, but a predicted hotter and wetter world may allow the expansion of tick ranges. Dermacentor andersoni and D. variabilis ticks are morphologically similar, co-occur throughout the Inland Northwest of Washington State, U.S.A., and both can be injected with pathogenic Rickettsia and Francisella bacteria. Differences in behavior and the potential role of endosymbiotic Rickettsia and Francisella in these ticks are poorly studied. We wanted to measure behavioral and ecological differences between the two species and determine which, if any, Rickettsia and Francisella bacteria - pathogenic or endosymbiotic - they carried. Additionally, we wanted to determine if either tick species may be selected for if the climate in eastern Washington becomes wetter or dryer. We found that D. andersoni is more resistant to desiccation, but both species share similar questing behaviors such as climbing and attraction to bright light. Both also avoid the odor of eucalyptus and DEET but not permethrin. Although both tick species are capable of transmitting pathogenic species of Francisella and Rickettsia, which cause tularemia and Rocky Mountain Spotted Fever, respectively, we found primarily non-pathogenic endosymbiotic strains of Francisella and Rickettsia, and only one tick infected with F. tularensis subspecies holarctica.

A Report on Molecular Detection and Phylogenetic Evaluation of Anaplasma marginale in Ticks and Blood Samples Collected from Cattle in District Layyah in Punjab (Pakistan)

Anaplasmosis is a tick-borne disease caused by obligate intercellular gram-negative bacteria, Anaplasma (A.) marginale. The present study reports on seasonal prevalence, epidemiology, and phylogeny of A. marginale in three cattle breeds from District Layyah, Southern Punjab, Pakistan. A total of 844 blood samples (Cross = 300, Holstein Friesian = 244, Sahiwal breed = 300) from apparently healthy cattle on seasonal basis were collected along with epidemiological data during May 2018 till April 2019. Polymerase chain reaction generated 265 base-pair amplicon specific for major surface protein-1b encoding gene of A. marginale in 8.6% (73/844) of enrolled cattle. The highest prevalence was observed during autumn (18.3%) followed by summer (9.7%) and winter season (7.1%). Holstein Friesian breed was most susceptible to A. marginale infection (13.1%) followed by Sahiwal (7.6%) and cross breed (6%). Representative amplified partial gene sequences of A. marginale were submitted to GenBank (Accession numbers MK032842 and MK032843). 37/844 (4.3%) Giemsa-stained blood smears were found positive for Anaplasma spp. Small number of ticks including Hyalomma anatolicum, Hyalomma excavatum, Rhipicephalus microplus, Haemaphysalis punctata were identified from cattle but none of them was found PCR positive for the presence of A. marginale. Analysis of epidemiological factors revealed that female cattle and farm with water supply from pool, farms where other dairy animals and dogs were living with cattle and dogs having ticks load on them had significant association with A. marginale prevalence. It was observed that white blood cell, lymphocytes (%), monocytes (%) hematocrit, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were significantly disturbed in A. marginale-positive than negative cattle.

First digital characterization of the transhumance corridors through Benin used by cattle herds from Burkina Faso and associated risk scoring regarding the invasion of Rhipicephalus (Boophilus) microplus

BACKGROUND

Livestock plays a key role in the macro-economy of West Africa and provides livelihoods for millions of people. The main cattle rearing strategy in West Africa is pastoralism, including transhumance, that is a seasonal migration of cattle with their herders. This adaptive strategy aims to optimize livestock access to water and pastures. However, it can favour pathogens and vectors transboundary spread. The aim of this study was to highlight firstly, the corridors and grazing areas used by Burkina Faso transhumant cattle herds going to Benin; secondly, the characteristics of departure and arrival areas of transhumance; and thirdly, the risk score related to introduction and spread of the invasive tick species, Rhipicephalus (Boophilus) microplus, in free areas.

METHODS AND PRINCIPAL FINDINGS

Therefore, GPS devices were given to 27 herders to monitor a full transhumance season between East Burkina Faso and North Benin. The analysis of 14,966 spots generated by the GPS devices revealed four main corridors and five main grazing areas used by cattle herds during transhumance. Statistical analysis of normalized difference vegetation index (NDVI), rainfall and temperature data, highlighted significant differences between departure and arrival areas. NDVI and rainfall are significantly higher in Benin than Burkina Faso, whereas temperature is significantly lower. Additionally, using biotic and abiotic parameters, a risk scoring was developed to predict the presence of Rhipicephalus (Boophilus) microplus at municipality level.

CONCLUSIONS AND SIGNIFICANCE

The better vegetation, temperature and rainfall conditions during the dry seasons in Benin attract cattle herds from Burkina Faso. The invasiveness and adaptability of Rhipicephalus (Boophilus) microplus added to the frequent stays of transhumant herds in infested areas suggest its potential introduction and establishment in free areas soon. Moreover, frequent intrusions of the transhumant cattle in the wildlife reserves are another risk of vectors and pathogen exchange between domestic and wild animals.

Epidemiological and Comparative Diagnostic Study of Anaplasma Spp. Infection in Goats from North-Eastern Algeria

Anaplasmosis is an infectious disease affecting goats and other ruminants. Our goal was to estimate the prevalence of Anaplasma spp. infections, and to identify different tick species in goa ts along with their associated risk factors. The epidemiology of Anaplasma spp. (A. ovis/A. marginale) was investigated from April to September 2016 in dairy goats from three different agro-ecological areas in the northeast region of Algeria (Guelma and El-Taref). We tested 182 goat sera using a MSP5 competitive ELISA (cELISA) test for IgG antibody screening, and by microscopic examination using the Giemsa (May-Greunwald-Giemsa) stain of 128 blood smears to detect intraerythrocytic inclusions bodies. The results demonstrated a total infection rate of 78.02 % and 42.18 % using cELISA and MGG, respectively. Only two species of ticks collected were identified, i. e. Rhipicephalus sanguineus (85.39 %) and Rhipicephalus bursa (14.60 %). Our study revealed that factors, such as the season, the type of farming, the hygienic status and the climatic conditions of the studied areas were found to be significantly associated with the tick infestation of goats (P < 0.05). The Anaplasma spp. infection prevalence was found to be highly dependent on the climatic conditions, the season (P < 0.05) and most closely related to the type of breeding and herd management (P = 0.000).

The evaluation of the Giemsa technique showed specificity and sensitivity of 60.71 % and 45.16 % respectively. Calculating the concordance between the two techniques revealed Cohen’s Kappa value of 0.038 in the range 0.21—0.40, which corresponded to a very low agreement. The McNemar test results showed that both tests gave significantly different results (P < 0.05). This work provides evidence for Anaplasma spp. in goats from north-eastern Algeria.

Detection of Hyalomma rufipes in a recently arrived asylum seeker to the EU

The importation of novel tick species to Europe and the emergence of tick-borne diseases have been of rising concern over the last decades. In May 2019, a total of 349 asylum seekers arrived in Malta by boat. Public health syndromic surveillance was conducted on all migrant boat arrivals. The incidental finding of a tick with anomalous morphology in a newly arrived migrant in Malta prompted an epidemiological investigation. Morphological identification of the tick followed by species identification using keys specific to North Africa was conducted and molecular testing for Crimean Congo haemorrhagic fever virus (CCHFV) was performed. Detailed interview and clinical examination of the case were conducted on arrival and follow-up interviews were undertaken 1- and 4-weeks post-arrival. A Hyalomma rufipes tick was identified on the chest of a 28-year-old male from Sudan. The patient reported malaise and headache on arrival. No further symptoms were reported during follow-up. There was no evidence of previous CCHFV infection or the presence of other ticks or pathogens on the patient. The investigation revealed that the H. rufipes tick had likely been acquired in Libya. This is the first report of the presence of a H. rufipes tick, the main vector for CCHFV, on a recently arrived migrant in Europe. This event highlights the importance of increasing awareness on the risk of tick-borne infections among recently arrived migrants in the Mediterranean countries and the need to consider tick screening as part of the health screening offered in the EU.

Impact of abiotic factors, habitat type and urban wildlife on the ecology of hard ticks (Acari: Ixodidae) in urban and peri-urban habitats

BACKGROUND

Ticks are increasingly acknowledged as significant vectors for a wide array of pathogens in urban environments with reports of abundant tick populations in recreational areas. The study aims to contribute to a better knowledge of the abiotic and biotic factors which impact the ecology of hard ticks in urban and peri-urban habitats in Romania.

METHODS

Questing ticks were collected by flagging in seven recreational locations, from four types of habitats in Cluj-Napoca, Romania: parks; gardens; a cemetery; and peri-urban forests. Hedgehogs, birds and micromammals were also sampled and searched for ticks, using standard methods (i.e. torch-based searches, ornithological mist nets, snap-traps, etc.), while vegetation was evaluated on surveyed areas. Data on questing ticks were converted to abundance indices. Mood's median tests were used to assess the relationship between the abiotic and biotic factors and the abundance of questing ticks.

RESULTS

Two species of questing ticks were found: Ixodes ricinus (96.8%) and Haemaphysalis punctata (3.2%). Ixodes ricinus was also the predominant engorged tick collected from urban wildlife. For I. ricinus the highest mean total abundance index/location (total no. of ticks/100 m2) was recorded in the urban gardens (3.79, 95% CI: ± 1.59) and parks (2.68, 95% CI: ± 0.75), whereas the lowest mean total abundance index was noted in the peri-urban forests (0.06, 95% CI: ± 0.03) and the urban cemetery (0.04, 95% CI: ± 0.02). The adults and nymphs of I. ricinus displayed a bimodal activity pattern, while the larvae showed a unimodal questing behaviour with an autumnal peak. Positive correlations were found between the mean total abundance index and the rise in the daily mean temperature and relative humidity, and between the global abundance of questing ticks and the presence of hedgehogs in the respective locations (P < 0.01).

CONCLUSIONS

Ticks were collected in all the recreational sites surveyed in Cluj-Napoca. Ixodes ricinus was the dominant questing and engorged tick species. Several abiotic and biotic factors shape the ecology of ticks in Cluj-Napoca city, with climate and the local presence of suitable hosts being the most important.

Failed Disruption of Tick Feeding, Viability, and Molting after Immunization of Mice and Sheep with Recombinant Ixodes ricinus Salivary Proteins IrSPI and IrLip1

To identify potential vaccine candidates against Ixodes ricinus and tick-borne pathogen transmission, we have previously sequenced the salivary gland transcriptomes of female ticks infected or not with Bartonella henselae. The hypothesized potential of both IrSPI (I. ricinus serine protease inhibitor) and IrLip1 (I. ricinus lipocalin 1) as protective antigens decreasing tick feeding and/or the transmission of tick-borne pathogens was based on their presumed involvement in dampening the host immune response to tick feeding. Vaccine endpoints included tick larval and nymphal mortality, feeding, and molting in mice and sheep. Whether the antigens were administered individually or in combination, the vaccination of mice or sheep elicited a potent antigen-specific antibody response. However, and contrary to our expectations, vaccination failed to afford protection against the infestation of mice and sheep by I. ricinus nymphs and larvae, respectively. Rather, vaccination with IrSPI and IrLip1 appeared to enhance tick engorgement and molting and decrease tick mortality. To the best of our knowledge, these observations represent the first report of induction of vaccine-mediated enhancement in relation to anti-tick vaccination.

Assessing human exposure to spotted fever and typhus group rickettsiae in Ontario, Canada (2013-2018): a retrospective, cross-sectional study

BACKGROUND

Assessing the burden of rickettsial infections in Ontario, Canada, is challenging since rickettsial infections are not reportable to public health. In the absence of reportable disease data, we assessed the burden of rickettsial infections by examining patient serological data and clinical information.

METHODS

Our retrospective, cross-sectional study included patients who had Rickettsia serological testing ordered by their physician, in Ontario, from 2013 to 2018. We tested sera from 2755 non-travel patients for antibodies against spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) using an indirect immunofluorescence assay (IFA) (positive IgG titers ≥1:64). We classified cases using a sensitive surveillance case definition: confirmed (4-fold increase in IgG titers between acute and convalescent sera with clinical evidence of infection), possible (single positive sera with clinical evidence) and previous rickettsial infection (single positive sera without clinical evidence). We classified cases seropositive for both SFGR and TGR as unspecified Rickettsia infections (URIs).

RESULTS

Less than 5% of all patients had paired acute and convalescent sera tested, and of these, we found a single, laboratory-confirmed SFGR case, with a 4-fold increase in IgG titers and evidence of fever, maculopapular rash and headache. There were 45 possible (19 SFGR, 7 TGR, 19 URI) and 580 previous rickettsial infection (183 SFGR, 89 TGR, 308 URI) cases. The rate of positive tests for SFGR, TGR and URI combined (all case classifications) were 4.4 per 100,000 population. For confirmed and possible cases, the most common signs and symptoms were fever, headache, gastrointestinal complaints and maculopapular rash. The odds of having seropositive patients increased annually by 30% (odds ratio = 1.3, 95% confidence interval: 1.23-1.39).

CONCLUSIONS

The rates of rickettsial infections in Ontario are difficult to determine. Based on confirmed and possible cases, rates are low, but inclusion of previous rickettsial infection cases would indicate higher rates. We highlight the need for education regarding the importance of testing acute and convalescent sera and consistent completion of the laboratory requisition in confirming rickettsial disease. We suggest further research in Ontario to investigate rickettsial agents in potential vectors and clinical studies employing PCR testing of clinical samples.

Morphological and molecular identification of ixodid tick species (Acari: Ixodidae) infesting cattle in Uganda

In Uganda, the role of ticks in zoonotic disease transmission is not well described, partly, due to limited available information on tick diversity. This study aimed to identify the tick species that infest cattle. Between September and November 2017, ticks (n = 4362) were collected from 5 districts across Uganda (Kasese, Hoima, Gulu, Soroti, and Moroto) and identified morphologically at Uganda Virus Research Institute. Morphological and genetic validation was performed in Germany on representative identified specimens and on all unidentified ticks. Ticks were belonging to 15 species: 8 Rhipicephalus species (Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus microplus, Rhipicephalus decoloratus, Rhipicephalus afranicus, Rhipicephalus pulchellus, Rhipicephalus simus, and Rhipicephalus sanguineus tropical lineage); 5 Amblyomma species (Amblyomma lepidum, Amblyomma variegatum, Amblyomma cohaerens, Amblyomma gemma, and Amblyomma paulopunctatum); and 2 Hyalomma species (Hyalomma rufipes and Hyalomma truncatum). The most common species were R. appendiculatus (51.8%), A. lepidum (21.0%), A. variegatum (14.3%), R. evertsi evertsi (8.2%), and R. decoloratus (2.4%). R. afranicus is a new species recently described in South Africa and we report its presence in Uganda for the first time. The sequences of R. afranicus were 2.4% divergent from those obtained in Southern Africa. We confirm the presence of the invasive R. microplus in two districts (Soroti and Gulu). Species diversity was highest in Moroto district (p = 0.004) and geographical predominance by specific ticks was observed (p = 0.001). The study expands the knowledge on tick fauna in Uganda and demonstrates that multiple tick species with potential to transmit several tick-borne diseases including zoonotic pathogens are infesting cattle.

Two-year monitoring of tick abundance and influencing factors in an urban area (city of Hanover, Germany)

Ticks may transmit a variety of human and animal pathogens. Prevalence of Borrelia spp., Rickettsia spp. and Anaplasma phagocytophilum in ticks has been monitored in the city of Hanover, Germany, since 2005. However, to determine the infection risk for humans and animals, not only pathogen prevalence, but also tick abundance and seasonality need to be taken into account. Therefore, the aim of this study was to investigate tick abundance at ten different collection sites in the city of Hanover, Germany. Collection of questing ticks was performed by the flagging method in the first and second half of each month during the tick season (April-October) in 2017 and 2018. At each 200 m² collection site, one of four 50 m² fields was sampled per visit on a rotational basis, resulting in 100 m² sampled per month. In addition, data on weather conditions, near-ground temperature, relative humidity and vegetation composition were noted at each collection event. In 2017, a total of 1770 ticks were collected, while 1866 ticks were collected in 2018. Ixodes ricinus was the most prevalent species (97.0 % of all ticks, 98.0 % of nymphs, 91.6 % of adults) followed by I. inopinatus (2.3 % of all ticks, 1.1 % of nymphs, 8.0 % of adults), I. frontalis (0.6 % of all ticks, 0.6 % of nymphs, 0.3 % of adults) and I. hexagonus (0.03 % of all ticks, 0.03 % of nymphs, 0.0 % of adults). Using generalized linear mixed modeling, density of I. ricinus and I. inopinatus in 2017 was significantly higher than in 2018. Regarding different landscape types, ticks were significantly more abundant in mixed forests than in parks, with more than 50 ticks/100 m² on average in both years. In urban parks, average tick density amounted to 15 ticks/100 m² in 2017 and 11 ticks/100 m² in 2018 and in broad-leaved forests average tick density was 13 and 18 ticks/100 m² in 2017 and 2018, respectively. Tick density showed a marked peak in June 2017 and in May 2018 at most sites, whereas a less pronounced peak was recognizable in September. Tick density varied considerably between collection sites. However, no statistically significant effect of (micro-)climatic variables, including near-ground temperature, relative humidity and saturation deficit, was found. Thus, further factors, such as the abundance of wildlife hosts, need to be considered in future studies to explain the differences between collection sites.