Tick Research Articles

Knowledge, attitudes, and practices towards vector-borne diseases in changing climate in Finland.

With climate change, the geographic distribution of some VBDs has expanded, highlighting the need for adaptation, and managing the risks associated with emergence in new areas. We conducted a questionnaire survey on the knowledge, attitudes, and practices (KAP) about vector-borne diseases (VBDs) among sample of Finnish residents. The questions were scored and the level of KAP was determined based on scoring as poor, fair, good, or excellent. Binary logistic regression analysis was used to evaluate the associations of different KAP levels with sex, age, education, and possible previous VPD infection. We received 491/1995 (25%) responses across the country and detected generally good knowledge, but only fair practices towards VBDs. Sex and age of the respondents were most often significantly associated with the level of KAP (P>0.05). Despite the generally good knowledge, we detected major gaps, especially regarding the distinction of tick-borne encephalitis and Lyme borreliosis (LB), risk of disease, and protective measures. Additionally, many respondents thought the vaccination protects against LB or tick bites. This calls for awareness raising on disease risk and prevention measures. With increasing cases and the effects of climate change, surveillance of VBDs communication to the general public should be strengthened.

Identification, seasonal prevalence, and preferred attachment sites of ixodid tick species infesting cattle in four municipalities of the province of Tiaret, northwest Algeria.

Ixodid ticks are important disease vectors that significantly impact animal health and cause considerable economic losses, particularly in tropical and subtropical countries. The aim of the present study was to determine the identity, seasonal distribution, and preferred attachment sites of adult ixodid tick species of cattle in four municipalities (Aïn El Hadid, Sidi Bakhti, Mechraa Safa, and Sidi Hosni) of the Province of Tiaret (north-west Algeria) between May 2022 and May 2023. A total of 317 cattle were randomly selected and examined for tick infestation; 108 (34.07%; 95% CI 28-39) were found to be infested by one or more species of ticks. The mean intensity of tick infestation was 16.22 ± 18.45 ticks per individual, while the mean abundance was 5.53 ± 13.21 ticks per examined cattle. Overall, 1,752 adult ixodid ticks were collected and identified, including 1,353 males and 399 females. Three genus and nine tick species were identified, including, H. excavatum (43.78%), H. marginatum (20.15%), H. lusitanicum (18.32%), H. scupense (8.73%), R. bursa (7.53%), H. impeltatum (0.74%), R. (Boophilus) annulatus (0.46%), R. sanguineus sensu lato (0.23%), and D. marginatus (0.06%). The highest discrepancy indices (D) were recorded for H. impeltatum (0.98), while the lowest was observed for H. excavatum (0.88). The overall discrepancy (D) values range from 0.88 to 0.98, indicating significant seasonal variability in the aggregation of ixodid ticks. The highest infestation rate recorded was in Ain El Hadid at 100%, followed by Sidi Bakhti at 79.76%, Mechraa Safa at 10.53%, and Sidi Hosni at 9.79%. H. excavatum, H. marginatum, H. lusitanicum, H. scupense, H. impeltatum, R. bursa, and R. (Boophilus) annulatus displayed significant variation across municipalities (p < 0.001). Seasonally, the highest abundance of adult ixodid tick infestations occurred in summer (38.01%), while the lowest was observed in autumn (17.29%). Significant seasonal variations were observed in the abundance of H. excavatum, H. marginatum, H. lusitanicum, and R. bursa (p < 0.001). Tick distribution was highest in zone 5 (95.43%), which includes the sternum, abdomen, udder, scrotum, and inner sides of the hind legs, while the lowest occurrence was in zone 1 (0.06%), which includes the head and ears. H. excavatum and H. lusitanicum showed a significant preference for Zone 5 (p < 0.001). The findings from the current study serve as a foundation for creating effective strategies to control tick populations on cattle in the Tiaret province.

Hsa-miR-548d-3p: a potential microRNA to target nucleocapsid and/or capsid genes in multiple members of the Flaviviridae family

IntroductionFlaviviridae comprise a group of enveloped, positive-stranded RNA viruses that are mainly transmitted through either mosquitoes or tick bites and/or contaminated blood, blood products, or other body secretions. These viruses cause diseases ranging from mild to severe and are considered important human pathogens. MicroRNAs (miRNAs) are non-coding molecules involved in growth, development, cell proliferation, protein synthesis, apoptosis, and pathogenesis. These small molecules are even being used as gene suppressors in antiviral therapeutics, inhibiting viral replication. In the current study, we used bioinformatic tools to predict a possible miRNA sequence that could be complementary to the nucleocapsid (NP) and/or capsid (CP) gene of the Flaviviridae family and provide an inhibitory solution.MethodsBioinformatics is a field of science that includes tremendous computational analysis, logarithms, and sequence alignments. To predict the right alignments between miRNA and viral mRNA genomes, we used computational databases such as miRBase, NCBI, and Basic Alignment Search Tool–nucleotides (BLAST-n).ResultsOf the 2,600 mature miRNAs, hsa-miR-548d-3p revealed complementary sequences with the flavivirus capsid gene and bovine viral diarrhea virus (BVDV) capsid gene and was selected as a possible candidate to inhibit flaviviruses.ConclusionAlthough more detailed in vitro and in vivo studies are required to test the possible inhibitory effects of hsa-miR-548d-3p against flaviviruses, this computational study may be the first step to study further, developing a novel therapeutic for lethal viruses within the Flaviviridae family using suggested candidate miRNAs.

Early transcriptomic changes at the skin interface during Powassan virus transmission by Ixodes scapularis ticks

IntroductionPowassan virus (POWV), a vector-borne pathogen transmitted by Ixodes ticks in North America, is the causative agent of Powassan encephalitis. As obligate hematophagous organisms, ticks transmit pathogens like POWV at the tick bite site, specifically during the initial stages of feeding. Tick feeding and salivary factors modulate the host’s immunological responses, facilitating blood feeding and pathogen transmission. However, the mechanisms of immunomodulation during POWV transmission remain inadequately understood. In this study, we investigated the global cutaneous transcriptomic changes associated with tick bites during POWV transmission.MethodsWe collected skin biopsies from the tick attachment sites at 1, 3, and 6 h after feeding by POWV-infected and uninfected ticks, followed by RNA sequencing of these samples. Differentially expressed genes were analyzed for pathway enrichment using gene ontology and pathway enrichment analyses.ResultsOur findings reveal that tick feeding alone significantly impacts the skin transcriptome within the first 1 to 3 h of tick attachment. Although early POWV transmission induces minimal changes in the local environment, a pronounced shift toward a proinflammatory state is observed 6 h after tick attachment, characterized by neutrophil recruitment and interleukin signaling.DiscussionThese transcriptomic data elucidate the dynamic changes at the tick bite site, transitioning from changes that assist blood meal acquisition to a proinflammatory phase that may facilitate viral dissemination.

Histological staining of tick bite skin biopsies for spirochetes and Powassan virus RNA.

Ixodes scapularis is a vector of several human pathogens in the United States, including Borrelia burgdorferi, the cause of Lyme disease, and Powassan virus (POWV), an emerging cause of severe encephalitis. Skin biopsies from tick bite sites are frequently collected and tested for the presence of spirochetes (Borrelia spp.), which remain elusive. POWV testing is not performed despite the increasing incidence of POWV encephalitis. To determine the utility of staining skin biopsies for tick-borne pathogens, formalin-fixed paraffin-embedded specimens from 2010 to 2023 were examined by hematoxylin and eosin, Warthin-Starry stain, spirochete immunohistochemistry, and POWV in situ hybridization (ISH). These assays were optimized by staining histological sections from whole ticks, from which spirochetes were detected in two out of 14 patient-derived specimens, and POWV RNA was detected in multiple experimentally infected ticks. None of the 36 skin biopsies were positive for spirochetes, including 20 with retained tick mouth parts and six from patients with positive Lyme serology. POWV ISH was negative in all biopsies, including one laboratory confirmed case. Combining patients with skin biopsies and whole ticks (n = 50), spirochetes were detected in specimens from only 1/5 (20%) patients with suspected erythema chronicum migrans (ECM). Although limited, our data suggest a poor correlation between ECM and the detection of spirochetes, findings in concordance with the published literature. Similarly, the absence of detectable POWV RNA in any of the tested skin biopsies or patient-derived ticks, including one laboratory confirmed case, suggest the limited utility of POWV ISH for clinical use without further analysis with a larger sample size.IMPORTANCETick-borne infections, including Lyme and Powassan encephalitis, cause significant morbidity and mortality and are challenging to diagnose and study in humans. We examined skin biopsies from patients with tick bites to look for direct evidence of microbes by histochemical, immunohistochemical, and in situ hybridization stains. To validate these assays, we also tested the same stains on histological sections from whole ticks infected with spirochetes or Powassan virus. Examination of skin biopsies using similar tools may prove valuable in studying the pathogenesis of diseases, such as southern tick-associated rash illness, for which a causative pathogen has not yet been identified.

Lectin Microarray Analysis of Salivary Gland Glycoproteins from the Arboviral Vector Aedes aegypti and the Malaria Vector Anopheles stephensi.

Salivary glands proteins but not glycoconjugates have been previously studied in mosquito vectors of human diseases. Glycoconjugates from salivary gland-derived proteins from human-feeding tick vectors can elicit hypersensitivity reactions which may also occur with mosquito bites. Protein glycoconjugate in salivary glands of the principal arboviral vector Aedes aegypti and the rapidly spreading malaria vector Anopheles stephensi were therefore investigated. Forty different lectins in a microarray were used to analyse glycoconjugates in salivary gland proteins from both mosquito species. Salivary gland glycoproteins of both mosquitoes possessed similar lectin-binding specificities. Lectin-binding profiles in both mosquitoes showed the significant presence of oligomannose N-linked glycans, O-linked glycans, a limited presence of glycan structures capped with terminal GalNAc, GlcNAc, β linked Gal, α1-6 linked fucose, and no detectable sialic acids or terminal α-linked Gal in salivary gland glycoproteins. Aedes aegypti and An. stephensi possess similar salivary gland protein glycoconjugates to mosquito larval tissues. They differ from arachnid ticks in lacking detectable α-gal epitopes that are responsible for red meat allergy caused by tick bites.

New Record of Rhipicephalus fulvus (Neumann, 1913) from Goats and Sheep in Northeastern Algeria After more than a Century.

Tick diversity in Algeria has garnered increasing interest due to its implications for animal health and zoonotic diseases. Recent reports of abnormal ulcerative lesions in goats and sheep in the Cheria region of northeastern Algeria have raised concerns about a potential association with tick infestations. The aim of this study is to hypothesize the potential involvement of ticks in these unusual lesions. A total of 52 tick specimens were collected from the affected animals, comprising 24 adult males, 24 adult females, and four engorged females. A morphological examination was performed to identify the tick species. The morphological analysis identified the non-engorged ticks as Rhipicephalus fulvus. The observed ulcerative lesions were likely caused by reactions to the tick's saliva. Notably, this finding marks the first recorded presence of R. fulvus in Algeria since its original description by Neumann in 1913. Identifying R. fulvus highlights its reemergence in the region and suggests a potential impact on livestock health. This discovery underscores the need for enhanced tick surveillance and further studies to understand the tick's origin, distribution, and role in animal health.

Documentation of ethnoveterinary knowledge and alternative practices for cattle tick control in Sekhukhune District, Limpopo Province, South Africa

IntroductionThe integration of traditional plant-based methods for controlling ectoparasites in the primary healthcare of livestock is progressively emerging as a crucial intervention to enhance livestock productivity in regions with limited resources, particularly in smallholder farming areas facing resource constraints. In Sekhukhune District, where livestock plays a vital role in rural livelihoods, cattle ticks present a significant challenge to cattle farming. This study aimed to document the ethnoveterinary practices employed by local communities to control cattle ticks, highlighting the use of alternative methods rooted in indigenous knowledge (IK).MethodsData were collected using a purposive sampling method to select traditional livestock keepers, herders, and community elders to uncover the plant-based treatments and management strategies used in tick control. In addition, a semi-structured questionnaire and a guided field survey were employed to collect data.ResultsA total of 250 participants, with an age range from 18 to over 60 years, were recruited. The result revealed that the elder participants, over 60 years of age, were more knowledgeable compared to the youth and adults. Furthermore, 28 plant species with potential acaricidal properties and other methods aimed at controlling cattle tick infestations were documented. Cissus quadrangularis was the most frequently cited species, which was widely distributed throughout the district.ConclusionIn addition, these results are framed within the larger context of sustainability, promoting eco-friendly cattle farming practices in Sekhukhune District while reducing reliance on conventional acaricides. By documenting this ethnoveterinary knowledge, the study contributes to the preservation of indigenous knowledge while advocating for sustainable approaches to livestock health management in rural areas. The study concludes with valuable insights into the selected local community’s traditional methods of managing tick infestations. Furthermore, the study underscores the significance of preserving and understanding indigenous knowledge in livestock health management, particularly in regions where conventional veterinary approaches may face challenges.

A seasonal matrix population model for ixodid ticks with complex life histories and limited host availability

AbstractMany vector‐borne diseases are sensitive to changes in land use and climate; hence, it is important to understand the factors that govern the vector populations. Ixodid ticks, which serve as vectors for multiple diseases, have a slow life cycle compared with many of their hosts. The observable questing population represents only a fraction of the total tick population and may include overlapping cohorts in each stage. The duration of each life stage (larvae, nymph, and adult) is variable and depends on factors such as the seasonal timing of questing, development, and host availability. Mathematical models are therefore essential to mediate how complex life cycle transitions and host interactions underpin the seasonal dynamics of the questing tick population. In this study, we develop a seasonal matrix population model for ixodid ticks feeding on a small and large host. The model has 17 stages representing the main life history stages (eggs, larvae, nymphs, and adults) combined with status of feeding, seasonal timing of feeding, and overwintering. The probability of finding a host depends on tick instar and host type, and density regulation is incorporated through limited host capacity. Using a life history representing Ixodes ricinus in Northern Europe as a baseline, we extract seasonal numbers of different parts of the tick population and calculate life history outcomes such as generation time and mean and variance of lifespan and of lifetime reproductive output. These results are compared with an alternative scenario of a southern life history. Secondly, we investigate (1) effects of seasonality in the small host availability on the seasonal numbers of tick stages and (2) effects of varying host availability and utilization of small versus large hosts by larvae and nymphs, on the seasonal numbers of questing ticks. Our results suggest that the small host availability is an important regulating factor through the feeding of larvae. Our model incorporates complex mechanisms underlying the seasonal composition of the tick population. It can be applied to different ixodid tick species and provides a framework for future investigations into intra‐ and interspecific variation in life history and population dynamics.

Epidemiological analysis and potential factors affecting the 2022-23 Crimean-Congo hemorrhagic fever outbreak in Iraq.

Crimean-Congo hemorrhagic fever (CCHF) is an acute tick-borne disease with a case fatality rate of up to 40% in humans, posing a significant health threat. This study investigates the 2022-23 CCHF outbreaks in Iraq, the highest recorded to date, and analyzes potential factors at the human-animal-environmental interface. Data from the Iraqi government, the World Health Organization, and the World Bank were used to analyze CCHF trends and affecting factors. This included epidemiological reports, clinical data, tick infestation and seroprevalence studies, and climate data. Descriptive and statistical analyses examined case trends, geographic and demographic characteristics, clinical manifestations, risk factors, seasonal patterns, and influencing factors. A sudden rise in CCHF cases began in southern Iraq in April 2022 and expanded across all governorates, with a shift toward urban areas. Higher incidence was observed among males, aged 25-44, and those involved in slaughtering. The most common clinical manifestation was fever (97%), followed by hemorrhagic symptoms (54%). Bleeding from the gums or mouth and subcutaneous bleeding were more frequent in patients with fatal outcomes. Seasonal patterns showed peaks during spring and fall, correlating with tick activity and potentially exacerbated by climate change. Tick infestation and seroprevalence studies indicated a high prevalence of Hyalomma ticks and CCHF seropositivity among domestic animals in southern Iraq (60%), consistent with the distribution of CCHF human cases. Iraq's ongoing CCHF outbreak demands multidisciplinary One Health strategies. The Iraqi government has adopted such a control strategy, contributing to regional and global efforts to enhance pandemic preparedness.

Taxonomic identification and prevalence of hard ticks on different breeds of sheep from district Quetta in Balochistan, Pakistan

Ticks, being ectoparasites, are vectors for the transmission of various pathogens that can infect animals and can also pose a significant threat to human health. Due to hot and humid climatic conditions across different agro-ecological regions of Pakistan, ticks are widespread and infest a diverse range of animal species. This study aimed for taxonomic identification and prevalence determination of ticks in sheep collected from four different marketplaces in the Quetta district of Balochistan. A total of 200 sheep from six different breeds, Balochi, Harnai, Turki, Mari wal, black Shinwari-Afghani, and Kooka, were examined, and ticks were collected from their five distinct anatomical regions. The species are identified over petri-dish and under microscope using their morphological features. Out of total 200 sheep, 107 were identified to be infested by ticks with an overall prevalence of 53.50 %. The class of ≤6 month's age are more prevalent and more prone to tick infestation, with tick prevalence of 55 %. The female sheep were found more prone to tick infestation (56 %) as compared to male species (51 %). A total of 559 species were documented including H. anatolicum, R. microplus, H. rufipes, H. dromedary, R. (Boophilus) annulatus, R. decoloratus, Ixodes Pilosus, R. camicasi, R. pravus, and R. turanicum. R. decoloratus was noted in higher abundance (N; 31) at larvae stage, while H. anatolicum are more in nymph stage (N: 30); the R. (Boophilus) annulatus species are dominating the adult sage (N: 60). The amount of tick infestation also varied according to the season and month of the year: in the summer, the highest number of sheep become infected with ticks, with July having the highest frequency of tick predominance; in the winter, the lowest prevalence of ticks is found in January. The specie abundance was noted to be 559, Specie richness to be 10, and the diversity was calculated as 0.93.

Serological evidence of Crimean-Congo haemorrhagic fever in domestic animals from eight regions of Namibia.

Crimean-Congo haemorrhagic fever (CCHF) is a viral zoonotic disease endemic to regions of Africa, the Balkans, the Middle East, and Asia, with increasing reports of cases in southern Europe. Human transmission occurs primarily through the bite of infected ticks and by body fluids from infected human. Crimean-Congo haemorrhagic fever virus (CCHFV) affects a broad host range, including both domestic and wild vertebrates. Recent studies have suggested a potential susceptibility of companion animals, posing an additional threat to public health. In the present study, the presence of CCHFV antibodies was evaluated by screening 374 dog and 238 cat serum samples collected from eight Namibian regions using a commercial enzyme-linked immunosorbent assay. Overall, dogs (11.50%) showed significantly higher odds of seropositivity (OR = 7.60; 95% CI = 3.02 - 25.51; p-value < 0.001) compared to cats (1.68%). Most of the positive dogs and all positive cats originated from the Kunene and Hardap regions. No other factors were found to affect seroprevalence. The limited development of farming systems in these regions, combined with the higher roaming activity of dogs, may suggest a greater exposure risk to wild animals or infected ticks. Tick species of the genus Hyalomma are not commonly reported to infest dogs in Namibia, and other tick species may also be involved in transmission. The detection of CCHFV antibodies in dogs and cats in Namibia should be considered by public health authorities as a potential threat, warranting further investigation to identify infection sources and risk factors. While the level and duration of viremia in companion animals, as well as their actual infectivity, remain unknown, efforts should focus on reducing contact between domestic pets, livestock, and wild animals, as well as regular prophylactic tick treatment of pets to prevent or minimise tick infestations.

Deciphering Rickettsia conorii metabolic pathways: a treasure map to therapeutic targets

Indian tick typhus is an infectious disease caused by intracellular gram-negative bacteria Rickettsia conorii (R. conorii). The bacterium is transmitted to humans through bite of infected ticks and sometimes by lice, fleas or mites. The disease is restricted to some areas with few cases but in last decade it is re-emerging with large number of cases from different areas of India. The insight in to genetic makeup of bacterial pathogens can be derived from their metabolic pathways. In the current study 18 metabolic pathways were found to be unique to the pathogen (R. conorii). A comprehensive analysis revealed 163 proteins implicated in 18 unique metabolic pathways of R. conorii. 140 proteins were reported to be essential for the bacterial survival, 46 were found virulent and 10 were found involved in resistance which can enhance the bacterial pathogenesis. The functional analysis of unique metabolic pathway proteins showed the abundance of plasmid conjugal transfer TrbL/VirB6, aliphatic acid kinase short chain, signal transduction response regulator receiver and components of type IV transporter system domains. The proteins were classified into six broad categories on the basis of predicted domains, i.e., metabolism, transport, gene expression and regulation, antimicrobial resistance, cell signalling and proteolysis. Further, in silico analysis showed that 88 proteins were suitable therapeutic targets which do not showed homology with host proteins. The 43 proteins showed hits with the DrugBank database showing their druggable nature and remaining 45 proteins were classified as novel drug targets that require further validation. The study will help to provide the better understanding of pathogens survival and embark on the development of successful therapies for the management of Indian tick typhus.

Molecular epidemiological survey of Babesia species infecting cattle in Paraguay

Paraguay, an agricultural country in South America, has a high prevalence of tick infestations in its cattle population due to warm temperatures, high humidity, and extensive grazing management practices. Consequently, Babesia infections, which are transmitted by ticks, might have a wide distribution in Paraguay, but the current status of these infections remains uncertain. Therefore, we aimed to assess the infection status of three clinically significant Babesia species, including Babesia bovis, Babesia bigemina, and Babesia naoakii, among cattle populations in Paraguay. Blood samples were collected from a total of 326 cattle across nine departments in Paraguay, and their DNAs were screened with species-specific PCR assays. Of the surveyed cattle, single infections of B. bovis and B. bigemina were detected in 24 (7.4 %) and 127 (39.0 %), respectively, while co-infection with both the parasite species was detected in 38 (11.7 %). In contrast, all of the surveyed cattle were negative for B. naoakii infection. The prevalence of B. bigemina-single infection was higher in the Eastern region (49.0 %) compared to the Western region (34.6 %), in cattle under extensive management (51.3 %) compared to those under semi-intensive management (34.6 %), and in Bos indicus cattle (50.3 %) compared to Bos taurus (15.8 %). Our findings demonstrated a wide distribution of B. bovis and B. bigemina infections among cattle in Paraguay, underscoring the importance of implementing effective control measures to reduce the potential economic losses associated with bovine babesiosis.

Experimental evidence of high tick infestation limiting chick growth and survival in a colonial seabird

AbstractWhile numerous studies have established correlations between parasite load and negative effects on their hosts, establishing causality is more challenging because parasites can directly compromise host condition and survival or simply opportunistically thrive on an already weakened host. Here, we evaluated whether Ixodes uriae, a widespread seabird tick, can cause a decrease in growth parameters (body mass, bill length and growth rates) and survival of chicks of a colonially seabird, the black-browed albatross (Thalassarche melanophris) breeding on New Island (West Falkland). To investigate this, we daily removed the ticks from 28 randomly selected chicks during their first 14 days of life (treated chicks) and compared their growth and survival with 49 chicks of a control group. The tick load on control chicks correlated negatively with their body mass, growth rates and survival. Comparisons between treated and control chicks demonstrated that tick infestation depleted body mass and hampered the growth of control chicks. Treated chicks had a higher survival rate than control ones to fledgling age, but not to 14 days old, suggesting that the delayed higher mortality on control chicks was caused by the accumulation of sub-lethal effects of ticks. This study experimentally demonstrates that high tick infestation can cause reduced host growth and survival.

How long do ticks live? A survey of lifespan, life cycle and longevity in Ixodida (Acari: Parasitiformes)

Ticks are hematophagous parasites transmitting pathogens to animals and humans. This review summarizes the current understanding of their lifespan, life cycles and longevity, which is essential for preventing and controlling tick-borne diseases. As of October 2022, the lifespan, longevity, and life cycle of 117 tick species (approximately 12.2% of the world's total) from 10 genera have been recorded. Most of this data is collected in laboratory conditions, with only a few investigated in the field studies. The life cycles of 110 tick species are summarized in 150 publications, while the adult longevity of 62 species is reported in 65 publications. Data on tick lifespan is limited to 26 species documented in 18 publications. It should be noted that the lifespan of most argasid ticks is much longer (ranging from 114–861 days to 10585 days) compared to ixodid ticks (ranging from 55–114 days to 252ؘ–387 days). Also, environmental and climate changes can affect ticks' distribution and activity globally. Therefore, monitoring the lifespan, life cycles, and longevity of ticks in the field is particularly important for predicting the spread of ticks.

New records of ticks (Acari: Ixodida) and Rickettsia species in El Salvador.

The tick fauna of El Salvador is currently represented by 10 species of hard ticks (family Ixodidae) and 2 species of soft ticks (family Argasidae). This study aimed to report new and additional records of ticks and rickettsiae in El Salvador. During 2019-2021, a total of 216 specimens of ticks were collected from eight host species (domestic and wild animals) and in the environment among 15 geographic localities of El Salvador. Combining morphological and molecular analyses, tick specimens were identified into the following 11 tick species: Amblyomma dissimile, Amblyomma longirostre, Amblyomma mixtum, Amblyomma ovale, Amblyomma cf. parvum, Amblyomma sabanerae, Amblyomma scutatum, Dermacentor panamensis, Ixodes boliviensis, Ornithodoros puertoricensis, and Otobius megnini. In addition, one free-living nymph was morphologically and molecularly identified as Ixodes sp., although closely related to Ixodes brunneus and Ixodes silvanus. Three rickettsial agents of the spotted fever group were identified: Rickettsia rhipicephali in D. panamensis; a Rickettsia endosymbiont in Ixodes boliviensis; and Rickettsia amblyommatis in A. cf. parvum. This study reports the first records of A. longirostre, D. panamensis, I. boliviensis, O. puertoricensis and O. megnini in El Salvador. In addition, the agents R. rhipicephali and Rickettsia sp. endosymbiont of I. boliviensis are also reported for the first time in the country. With the present study, the current tick fauna of El Salvador increases to 17 species, being 13 Ixodidae and 4 Argasidae, including the addition of one genus to each of these two families (Ixodes and Otobius, respectively).

Teratological abnormalities in hard ticks (Acari: Ixodidae) from Pakistan.

Studying teratological abnormalities in ticks are taxonomically important because this poorly understood biological phenomenon causes difficulties in tick's identification. Globally, reports regarding these abnormalities in ticks, reasons of their causes and their impacts are scarce. According to the available published data, there are no studies regarding teratological abnormalities in ticks from Pakistan. Herein, ticks examined for these abnormalities were museum deposited, collected from buffalos, cattle, camels, goats and sheep in 17 districts of Pakistan during 2017-2023. The abnormalities were observed in 88 out of 3279 (2.68%) ticks, representing eight ixodid species (Rhipicephalus microplus, Rhipicephalus turanicus, Rhipicephalus haemaphysaloides, Haemaphysalis bispinosa, Haemaphysalis montgomeryi, Hyalomma anatolicum, Hyalomma scupense, Hyalomma dromedarii). Among abnormal ticks, 67 abnormalities were characterized as local, 12 as general and nine as a combination of both. Local abnormalities were observed in the scutum, palpal segments, anal aperture, spiracular plates, ventral plates, caudal appendage, festoons and posterior grooves. Also, the constrictions and excavations of body parts were observed. General abnormalities included irregular idiosoma and lateral idiosomal bifurcation. This study, for the first time, highlights the diversity of teratological abnormalities in Pakistani ticks, and are reported in in Hy. anatolicum, Ha. bispinosa and Ha. montgomeryi for the first time.

The AxBioTick study – immune gene expression signatures in human skin bitten by Borrelia-infected versus non-infected ticks

BackgroundBorrelia infection is caused by Borrelia burgdorferi sensu lato and transmitted by Ixodes ricinus ticks, a common tick-borne infection in Northern Europe. The establishment of Borrelia infection depends on transmission of the spirochetes, as well as the immune response generated in the skin after a bite. Here we aim to investigate the local immune response in the skin after a tick bite and assess the possible direct effects of Borrelia, by applying gene expression analysis of the immune response in skin exposed to Borrelia-infected and non-infected ticks, respectively.MethodsSkin biopsies from the study participants were taken 7–10 days after the tick-bite. The ticks and skin biopsies were analysed by real-time PCR for Borrelia spp. and other tick-borne pathogens. Dermal transcriptome profiles derived from RNA sequencing with focus on immune system regulation were created. In addition, we performed enrichment analysis of dermal transcriptome profiles with focus on immune system regulation.ResultsSkin biopsies exposed to a Borrelia-positive tick induced an overall higher expression of immune-related genes. Cytokines involved in the regulation of T-cell and macrophage activation, pro-inflammatory regulators and Toll-like receptor 2, 3 and 7 involved in pathogen recognition were upregulated in skin exposed to Borrelia, although Borrelia DNA was not detected in the biopsies.ConclusionThe evidence of upregulation of genes in Borrelia exposed skin suggests an influence on the immune system of ticks and spirochetes. Characterization of Borrelia-associated gene expression signatures in the skin could contribute to future diagnostics and increase our understanding of the development of various manifestations of Borrelia infection.

Assessment of occupational exposure of soldiers to Lyme disease and Borrelia miyamotoi disease in selected military training areas from northern Poland.

Ixodes ricinus tick is a vector of bacteria of Borreliella genus and Borrelia miyamotoi. Exposure to ticks constitutes occupational risk to soldiers, but the current knowledge on this subject is still limited. Therefore, the aim of this study was to evaluate tick abundance and prevalence of infection with Borreliella spp. and/or B. miyamotoi. Ticks were collected from vegetation on Drawsko, Ustka and Orzysz military training areas. Additionally, ticks infesting soldiers were also obtained. Ticks were examined by nested PCR and sequencing of flaB gene fragment. General Linear Models of One Variable was used for analysis of mean tick abundance and Maximum Likelihood technique based on log-linear analysis of contingency tables was used for analysis of prevalence of pathogens in ticks. Molecular phylogenetic analyses were also performed. 852 I. ricinus were collected from vegetation from three military areas. The overall mean abundance of ticks was almost 4 ticks/100 m2. Season of study had a significant effect on density of total ticks, infected nymphs and females and infected nymphs, which were higher in spring-early summer. Total prevalence of pathogens was 25.7% in 711 questing ticks, and 16.0% in 282 I. ricinus collected from soldiers. Six species of Borreliella and Borrelia were identified with predominance of B. afzelii. It should be assumed that there is a risk for soldiers of acquiring infection after tick bite. The awareness of presence of pathogens in ticks should be raised in military.