Haemaphysalis longicornis calreticulin is not an effective molecular tool for tick bite diagnosis and disruption of tick infestations.

BACKGROUND: Tick calreticulin (CRT) is a calcium-binding protein secreted into the host during blood feeding. It has been used as a biomarker of tick exposure and has potential as an anti-tick vaccine, but there is no information about these uses for Haemaphysalis longicornis CRT (HlCRT). We synthesized recombinant H. longicornis CRT (rHlCRT) and evaluated its potential for tick bite diagnosis and for disrupting tick infestations. METHODS: The responses of mice and rabbits exposed to H. longicornis ticks were measured with ELISA to determine the antibody level against rHlCRT. To evaluate the effects of rHlCRT-induced anti-tick immunity, engorgement weight, tick engorgement index (TEI), feeding duration, ecdysis rate, and egg weight per engorged tick were compared between ticks fed on immunized and normal mice. RESULTS: Mean anti-tick CRT antibody levels in sera collected from mice at 1 and 15 days after primary tick exposure were not significantly different from the mean antibody levels in negative control mice that were not bitten by ticks (all P values > 0.05). No significant anti-HlCRT IgG responses developed in mice after second exposure to tick bites compared with the level of anti-HlCRT antibody response in negative control mice (all P values > 0.25). For rabbits, no significant differences in the antibody levels were observed in animals before challenge infestation and after tick exposures, and in animals after two tick exposures (all P values > 0.10). There were no significant differences in the body weight of ticks fed on immunized and normal mice (all P values > 0.15). No significant differences in TEI were observed between ticks fed on immunized mice and normal control mice (all P values > 0.50). There were no significant differences in feeding duration for female ticks, and feeding duration and ecdysis rate for nymphs in the experimental and control groups (all P values > 0.10 for feeding duration and P value = 0.19 for ecdysis rate). We did not observe a significant difference in egg weight per tick in the rHlCRT-immunized and the control groups (P = 0.88). CONCLUSIONS: HlCRT in H. longicornis tick saliva proteins appears to be nonimmunogenic to mammalian hosts like mice and rabbits. Vaccination with rHlCRT did not generate effective immunity against parthenogenetic and bisexual H. longicornis nymphs or female ticks. These results indicate that HlCRT is not a suitable molecular candidate for H. longicornis tick bite diagnosis and not effective for the disruption of tick infestations.

Putative Otobius megnini-associated clinical signs in horses in South Africa (2012-2018).

Otobius megnini has been associated with certain clinical conditions in horses in both California and Mexico. A number of cases similar to those described previously have been identified by the author in South Africa. This case report summarises these cases to demonstrate that the clinical condition occurs readily in South Africa and may be increasing in occurrence. The disease has minimal coverage in the literature making it more likely that a veterinarian, unfamiliar with the disease, will miss the diagnosis. The author would like to make veterinarians aware of this as a potential differential diagnosis. This study is a retrospective review of clinical data. Clinical records of patients with similar clinical signs and treatment were reviewed and grouped together as relevant cases for this case report. Ten cases of O. megnini associated neuromuscular dysfunction are reported, suggesting a link between the occurrence of the tick and the clinical condition. Clinical signs include third eyelid prolapse, localised muscle fasciculations, elevated heart rate and limb stamping. Serum chemistry changes commonly show increased aspartate aminotransferase and creatine kinase enzymes activities. The occurrence of the ticks within South Africa and the increasing number of cases presented demonstrate the need for more investigation into the pathophysiology of this condition.

Tick paralysis in a free-ranging bobcat (Lynx rufus).

CASE DESCRIPTION: A free-ranging male bobcat (Lynx rufus) was evaluated because of signs of pelvic limb paralysis. CLINICAL FINDINGS: Physical examination of the anesthetized animal revealed tick infestation, normal mentation, and a lack of evidence of traumatic injuries. Radiography revealed no clinically relevant abnormalities. Hematologic analysis results were generally unremarkable, and serologic tests for exposure to feline coronavirus, FeLV, FIV, and Toxoplasma gondii were negative. Results of PCR assays for flea- and common tick-borne organisms other than Bartonella clarridgeiae were negative. TREATMENT AND OUTCOME: Ticks were manually removed, and the patient received supportive care and fipronil treatment. The bobcat made a full recovery within 72 hours after treatment for ticks, and a presumptive diagnosis of tick paralysis was made. Identified tick species included Dermacenter variabilis, Amblyomma americanum, and Ixodes scapularis. CLINICAL RELEVANCE: To the authors' knowledge, tick paralysis has not previously been reported in felids outside Australia. This disease should be considered a differential diagnosis in felids, including exotic cats, with signs of neuromuscular disease of unknown etiopathogenesis.

Larval tick infestation causing an eruption of pruritic papules and pustules.

Ticks are well-documented human parasites and vectors of infectious disease. The larval ("seed") stage is 1 of 3 motile life stages, and larval ticks have been known to attack in droves, causing diffuse pruritic erythematous papules and pustules. In the absence of close examination, larval tick infestation can easily be missed in the wide differential for this clinical presentation. We present 2 cases of larval tick infestation occurring during the summer within the same month at a single institution. Our purpose is to encourage physicians to include larval tick infestation when generating a differential diagnosis for diffuse pruritic erythematous papules and pustules.

Citizen science informs human-tick exposure in the Northeastern United States.

BACKGROUND: Tick-borne disease is the result of spillover of pathogens into the human population. Traditionally, literature has focused on characterization of tick-borne disease pathogens and ticks in their sylvatic cycles. A limited amount of research has focused on human-tick exposure in this system, especially in the Northeastern United States. Human-tick interactions are crucial to consider when assessing the risk of tick-borne disease since a tick bite is required for spillover to occur. METHODS: Citizen scientists collected ticks from the Northeastern US through a free nationwide program. Submitted ticks were identified to species, stage, and sex. Blacklegged ticks, Ixodes scapularis, were tested for the presence of Borrelia burgdorferi sensu lato (s.l.) and hard-tick relapsing fever Borrelia. Seasonality of exposure and the citizen science activity during tick exposure was recorded by the citizen scientist. A negative binomial model was fit to predict county level CDC Lyme disease cases in 2016 using citizen science Ixodes scapularis submissions, state, and county population as predictor variables. RESULTS: A total of 3740 submissions, comprising 4261 ticks, were submitted from the Northeastern US and were reported to be parasitizing humans. Of the three species submitted, blacklegged ticks were the most prevalent followed by American dog ticks and lone star ticks. Submissions peaked in May with the majority of exposure occurring during every-day activities. The most common pathogen in blacklegged ticks was B. burgdorferi s.l. followed by hard-tick relapsing fever Borrelia. Negative binomial model performance was best in New England states followed by Middle Atlantic states. CONCLUSIONS: Citizen science provides a low-cost and effective methodology for describing the seasonality and characteristics of human-tick exposure. In the Northeastern US, everyday activities were identified as a major mechanism for tick exposure, supporting the role of peri-domestic exposure in tick-borne disease. Citizen science provides a method for broad pathogen and tick surveillance, which is highly related to human disease, allowing for inferences to be made about the epidemiology of tick-borne disease.

Ticks in wild animals at a resort and the first documentation of Amblyomma sculptum infesting Emu (Dromaius novaehollandiae) / Carrapatos em animais selvagens em um resort e o primeiro registro de Amblyomma sculptum infestando Emu (Dromaius novaehollandiae)

Abstract The study aimed to identify species of ticks present in the environment and among captive animals, in Mangaratiba, Rio de Janeiro, Brazil. Ticks were isolated from captive animals by manual examination and free-living ticks in the environment were captured using the flannel drag technique. A total of 91 ticks were obtained (51 adults, 25 nymphs and 15 larvae). The specimens were identified morphologically as Amblyomma sp., Amblyomma dubitatum, Amblyomma ovale and Amblyomma sculptum , and were distributed among five species of native mammals and an exotic bird. This study also reports the first case of infestation of the Australian emu (Dromaius novaehollandiae) by A. sculptum.

Resumo O estudo teve como objetivo identificar espécies de carrapatos presentes no ambiente e entre animais de cativeiro em Mangaratiba, Rio de Janeiro, Brasil. Os carrapatos foram removidos manualmente de animais de cativeiro e no ambiente usando a técnica de arrasto em flanela. Um total de 91 carrapatos foram capturados (51 adultos, 25 ninfas e 15 larvas). Os espécimes foram identificados morfologicamente como Amblyomma sp., Amblyomma dubitatum, Amblyomma ovale e Amblyomma sculptum, e foram distribuídos entre cinco espécies de mamíferos nativos e uma ave exótica. Este estudo também relata o primeiro caso de infestação do emu australiano (Dromaius novaehollandiae) por A. sculptum .

Ticks in wild animals at a resort and the first documentation of Amblyomma sculptum infesting Emu (Dromaius novaehollandiae).

The study aimed to identify species of ticks present in the environment and among captive animals, in Mangaratiba, Rio de Janeiro, Brazil. Ticks were isolated from captive animals by manual examination and free-living ticks in the environment were captured using the flannel drag technique. A total of 91 ticks were obtained (51 adults, 25 nymphs and 15 larvae). The specimens were identified morphologically as Amblyomma sp., Amblyomma dubitatum, Amblyomma ovale and Amblyomma sculptum , and were distributed among five species of native mammals and an exotic bird. This study also reports the first case of infestation of the Australian emu (Dromaius novaehollandiae) by A. sculptum.

Detection of Ehrlichia ruminantium infection in cattle in Cameroon.

OBJECTIVES: Ehrlichia ruminantium infection (heartwater) is a major constraint that impacts negatively on the cattle industry development in sub-Saharan Africa and so far, little is known of the presence of heartwater in cattle in Cameroon. This study sought to investigate the prevalence of E. ruminantium infection in cattle in Cameroon and to determine the predictors of infection. RESULTS: A species-specific semi-nested pCS20 polymerase chain reaction was used to screen the buffy coats from 182 cattle (comprising 82 cattle that received intensive tick control regimen and 100 cattle on strategic tick control) from two study sites in Cameroon for E. ruminantium DNA in a cross-sectional study. E. ruminantium infection was confirmed in 12 (6.6%) of the 182 cattle comprising 11 that received intensive tick control and one on strategic tick control. Of the 12 cattle detected, 11 were apparently healthy and one was clinically diagnosed of heartwater. All DNA sequences of pCS20 amplicons were identical to each other (a representative sequence deposited in GenBank under accession number JQ039939). These findings which have veterinary and epidemiological significance, suggest the need for further investigation to determine the extent and role of heartwater in cattle in Cameroon.

What's eating you? Ixodes tick and related diseases, part 2: diagnosis and treatment of regional tick-borne diseases.

The Ixodes tick is an important arthropod vector in the transmission of human disease. Although Lyme disease is the most prevalent zoonosis transmitted by Ixodes ticks, other less common diseases may be encountered, including human granulocytic anaplasmosis, babesiosis, Powassan virus infection, tick-borne encephalitis, Borrelia miyamotoi disease, and tick paralysis. In part 2 of this review, disease presentation, diagnosis, and treatment of these less commonly encountered tick-borne diseases are discussed.

[Tick Infestation of the Eyelid: Case Report and Literature Review]. / Parasitose Palpebral por Carraça: Caso Clínico e Revisão da Literatura.

Tick infestation is rarely seen in ophthalmological practice. We report the case of a 73-year-old woman who presented with edema and erythema of her right upper eyelid. Biomicroscopic examination revealed a tick firmly attached to the eyelid margin. The tick was successfully removed using fine tweezers, and within a few days, the patient had fully recovered without sequelae. Ticks are a threat to public health as they are known vectors of numerous infectious agents responsible for serious pathologies such as Lyme disease. Ticks may also induce cutaneous local reactions, and more rarely, tick paralysis. Since morbidity increases substantially with the duration of the infestation, the tick should be completely removed as soon as possible, and patients should be aware about possible signs of tick related diseases.

No âmbito da prática clínica oftalmológica, as parasitoses por carraças são incomuns. Os autores descrevem o caso clínico de uma doente de 73 anos observada por edema e eritema da pálpebra superior direita. O exame oftalmológico revelou uma carraça aderente à margem palpebral. A carraça foi removida usando uma pinça fina, e poucos dias após, houve regressão total dos sinais inflamatórios, sem registo de complicações. O parasitismo por carraças representa uma ameaça para a Saúde Pública, pois as carraças são vetores de inúmeros agentes infeciosos responsáveis por patologias potencialmente graves, como a doença de Lyme. As carraças podem também induzir reações cutâneas locais e, mais raramente, paralisia neuromuscular. A morbilidade associada à picada da carraça aumenta com a duração da parasitação, pelo que a carraça deve ser removida o mais rápido possível, e os doentes devem ser alertados para os sinais de possíveis complicações locais e sistémicas.

Assessment of using recombinant Ixodes ricinus AV422 saliva protein for confirmation of tick bites in hunting dogs as naturally infested hosts.

Due to the recorded spreading of ticks in past years, a higher incidence of tick-borne diseases (TBDs) can be expected in the future in endemic areas, but can also pose an emerging public health concern in areas where they have not yet been recognized. Assessment of the exposure of vulnerable hosts to ticks would be a very helpful tool for TBD epidemiological studies, as well as for their proper managing. To confirm previous tick bites, the method of choice is detection of antibodies in host serum as markers developed against injected tick saliva proteins during feeding. We recently showed that the recombinant form of Ixodes ricinus AV422 saliva protein (rIrAV422) can serve for detection of markers in experimentally infested rats. Here we examine whether it can be used in the same manner in naturally exposed hosts. We chose hunting dogs as good sentinel animals. The study group consisted of 15 dogs that varied in breed, age, sex, previous tick infestation history and repellent treatment. Western blot analysis with rIrAV422 as an antigen confirmed the presence of tick bite markers in all analysed dogs. For some of the dogs, their previous tick infestation history was unclear, which emphasizes the usefulness of rIrAV422 for revealing it. Since hunting dogs are naturally infested with different ticks, the potential of rIrAV422 in assessment of general exposure to ticks is highlighted. Use of rIrAV422 can also be helpful in veterinary practice and research as a tool for validation of the efficiency of tick repellent products.

Metabolic differentiation of early Lyme disease from southern tick-associated rash illness (STARI).

Lyme disease, the most commonly reported vector-borne disease in the United States, results from infection with Borrelia burgdorferi. Early clinical diagnosis of this disease is largely based on the presence of an erythematous skin lesion for individuals in high-risk regions. This, however, can be confused with other illnesses including southern tick-associated rash illness (STARI), an illness that lacks a defined etiological agent or laboratory diagnostic test, and is coprevalent with Lyme disease in portions of the eastern United States. By applying an unbiased metabolomics approach with sera retrospectively obtained from well-characterized patients, we defined biochemical and diagnostic differences between early Lyme disease and STARI. Specifically, a metabolic biosignature consisting of 261 molecular features (MFs) revealed that altered N-acyl ethanolamine and primary fatty acid amide metabolism discriminated early Lyme disease from STARI. Development of classification models with the 261-MF biosignature and testing against validation samples differentiated early Lyme disease from STARI with an accuracy of 85 to 98%. These findings revealed metabolic dissimilarity between early Lyme disease and STARI, and provide a powerful and new approach to inform patient management by objectively distinguishing early Lyme disease from an illness with nearly identical symptoms.

Human otoacariasis caused by Amblyomma testudinarium: Diagnosis and management: Case report.

RATIONALE: Tick infestation of the external auditory canal (EAC) constitutes <1% of all patients presenting with ear complaints. Consequently, parameters for the diagnosis and management of ticks in the EAC have not been established. PATIENT CONCERNS: We report 2 cases of EAC infestation by Amblyomma testudinarium in 2 female patients, aged 12- and 72 years old. DIAGNOSES INTERVENTIONS AND OUTCOMES: In both patients, otoscopic examination revealed engorged ticks attached to the ear canal. The 12-year-old girl had a narrow EAC, necessitating slight dislodging of the tick to determine if its mouth parts were embedded in the EAC skin. The tick's mouth parts were confirmed to be free, enabling complete removal of the tick. The 72-year-old woman had a wide EAC, enabling tick removal using Hartman's forceps because the tick's mouth parts were confirmed to be free of the skin. Prophylactic tetracycline (200 mg/day) was administered to each patient for 7 days; neither showed any signs of fever or rash. LESSONS: This report describes 2 patients with A testudinarium infestation of the EAC, and proposes a simple, noninvasive protocol for determining if the tick is anchored to the ear canal.

The use of infrared images to detect ticks in cattle and proposal of an algorithm for quantifying the infestation.

This paper presents a study on the use of low resolution infrared images to detect ticks in cattle. Emphasis is given to the main factors that influence the quality of the captured images, as well as to the actions that can increase the amount of information conveyed by these images. In addition, a new automatic method for analyzing the images and counting the ticks is introduced. The proposed algorithm relies only on color transformations and simple mathematical morphology operations, thus being easy to implement and computationally light. Tests were carried out using a large database containing images of the neck and hind end of the animals. It was observed that the proposed algorithm is very effective in detecting ticks visible in the images, even if the contrast with the background is not high. On the other hand, due to both intrinsic and extrinsic factors, the thermographic images used in this study did not always succeed in creating enough contrast between ticks and cattle's hair coat. Although these problems can be mitigated by following some directives, currently only rough estimates for tick counts can be achieved using infrared images with low spatial resolution.

Severe meningeal fibrinoid vasculitis associated with Theileria taurotragi infection in two short-horned Zebu cattle.

The Authors describe a severe vasculitis with fibrinoid necrosis of the meningeal arteries observed in two brains of indigenous short-horn zebu (Bos indicus) cattle, with bovine cerebral theileriosis (BCT) caused by a tick-transmitted hemoprotozoan, Theileria taurotragi, from Northern Tanzania. In the Author's opinion, the role of T. taurotragi infection in the angiocentric and angiodestructive detected features remains to be evaluated. A possible immunopathologic cancerous mechanism, secondary to the lymphoid deregulation, could be involved. This report suggests further studies to better characterize the lymphoid cell involvement in the pathogenesis of the meningeal vascular lesions by T. taurotragi.