What's eating you? clinical manifestations of Dermacentor tick bites.

Dermacentor ticks are hard ticks found throughout most of North America and are easily identified by their large size, ornate scutum, and prominent dorsal pits. They are important disease vectors and are implicated in transmission of Rocky Mountain spotted fever (RMSF), Colorado tick fever, tularemia, and erlichiosis. They also are an important cause of fatal tick paralysis.

Rare Cause of Facial Palsy: Case Report of Tick Paralysis by Ixodes Holocyclus Imported by a Patient Travelling into Singapore from Australia.

BACKGROUND: Ticks are blood-sucking arachnids that feed on all classes of vertebrates, including humans. Ixodes holocyclus, also known as the Australian Paralysis Tick, is capable of causing a myriad of clinical issues in humans and companion animals, including the transmission of infectious agents, toxin-mediated paralysis, allergic and inflammatory reactions, and mammalian meat allergies in humans. The Australian Paralysis Tick is endemic to Australia, and only two other exported cases have been reported in the literature. CASE REPORT: We report the third exported case of tick paralysis caused by I. holocyclus, which was imported on a patient into Singapore. We also discuss the clinical course of the patient, the salient points of management, and the proper removal of this tick species. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: With increasing air travel, emergency physicians need to be aware of and to identify imported cases of tick paralysis to institute proper management and advice to the patient. We also describe the tick identification features and proper method of removal of this tick species.

The relationship between the Southern Oscillation Index, rainfall and the occurrence of canine tick paralysis, feline tick paralysis and canine parvovirus in Australia.

The aim of this study was to describe the association between climate, weather and the occurrence of canine tick paralysis, feline tick paralysis and canine parvovirus in Australia. The Southern Oscillation Index (SOI) and monthly average rainfall (mm) data were used as indices for climate and weather, respectively. Case data were extracted from a voluntary national companion animal disease surveillance resource. Climate and weather data were obtained from the Australian Government Bureau of Meteorology. During the 4-year study period (January 2010-December 2013), a total of 4742 canine parvovirus cases and 8417 tick paralysis cases were reported. No significant (P ≥ 0.05) correlations were found between the SOI and parvovirus, canine tick paralysis or feline tick paralysis. A significant (P < 0.05) positive cross-correlation was found between parvovirus occurrence and rainfall in the same month (0.28), and significant negative cross-correlations (-0.26 to -0.36) between parvovirus occurrence and rainfall 4-6 months previously. Significant (P < 0.05) negative cross-correlations (-0.34 to -0.39) were found between canine tick paralysis occurrence and rainfall 1-3 months previously, and significant positive cross-correlations (0.29-0.47) between canine tick paralysis occurrence and rainfall 7-10 months previously. Significant positive cross-correlations (0.37-0.68) were found between cases of feline tick paralysis and rainfall 6-10 months previously. These findings may offer a useful tool for the management and prevention of tick paralysis and canine parvovirus, by providing an evidence base supporting the recommendations of veterinarians to clients thus reducing the impact of these diseases.

Tick paralysis in Australia caused by Ixodes holocyclus Neumann.

Ticks are obligate haematophagous ectoparasites of various animals, including humans, and are abundant in temperate and tropical zones around the world. They are the most important vectors for the pathogens causing disease in livestock and second only to mosquitoes as vectors of pathogens causing human disease. Ticks are formidable arachnids, capable of not only transmitting the pathogens involved in some infectious diseases but also of inducing allergies and causing toxicoses and paralysis, with possible fatal outcomes for the host. This review focuses on tick paralysis, the role of the Australian paralysis tick Ixodes holocyclus, and the role of toxin molecules from this species in causing paralysis in the host.

Biochemical perspectives on paralysis and other forms of toxicoses caused by ticks.

Tick toxicoses, of which paralysis is the most widespread and dominant form, are important elements of pathogenesis induced by ticks. Tick paralysis is the most widespread and dominant form of tick toxicoses. Non-paralytic forms of tick toxicoses do occur and evidence suggests that these forms of toxicoses are not evolutionary related. While functional significance has been suggested for tick toxins, the advantages for tick survival in general are not clear. This review considers the molecular nature of tick toxins, the possibility that tick toxins have originated more than once independently and whether these toxins could have unrecognized benign functions.

Pathogenic mechanisms of sand tampan toxicoses induced by the tick, Ornithodoros savignyi.

The tick, Ornithodoros savignyi has been implicated in inducing paralysis and tampan toxicosis. In this study, a basic toxin (TSGP4) was identified and the presence of an acidic toxin (TSGP2) was confirmed. Both basic and acidic toxins were more lethal than previously described, with TSGP4 (34microg) and TSGP2 (24microg) causing mortality of adult mice within 30min. Pathological effects on the cardiac system, notably of salivary gland extract on an isolated rat heart perfusion system and of purified toxins on mouse electrocardiogram patterns could be observed. TSGP4 caused Mobitz type ventricular block, while TSGP2 induced ventricular tachycardia. Conversely, fractions from reversed phase high performance liquid chromatography preparations caused paralysis-like symptoms of the limbs after only 48h. The toxins also differ from previously described tick paralysis toxins in terms of molecular behavior and properties. These results indicate that tampan toxicoses and tick paralysis are unrelated pathogenic phenomena.

Tick paralysis: 33 human cases in Washington State, 1946-1996.

Tick paralysis is a preventable cause of illness and death that, when diagnosed promptly, requires simple, low-cost intervention (tick removal). We reviewed information on cases of tick paralysis that were reported to the Washington State Department of Health (Seattle) during 1946-1996. Thirty-three cases of tick paralysis were identified, including 2 in children who died. Most of the patients were female (76%), and most cases (82%) occurred in children aged <8 years. Nearly all cases with information on site of probable exposure indicated exposure east of the Cascade Mountains. Onset of illness occurred from March 14 to June 22. Of the 28 patients for whom information regarding hospitalization was available, 54% were hospitalized. Dermacentor andersoni was consistently identified when information on the tick species was reported. This large series of cases of tick paralysis demonstrates the predictable epidemiology of this disease. Improving health care provider awareness of tick paralysis could help limit morbidity and mortality due to this disease.

Neurologic aspects of North American zoonoses.

Neurologic dysfunction is a frequent presentation or complication of zoonotic infections. The differential diagnosis is broad and will include nonzoonotic diseases as well. Patterns of neurologic findings, systemic signs of infection, and epidemiologic risk factors are useful in the approach to diagnosis and initial empiric treatment of the patient with suspected zoonotic infection. Associations between these patterns and specific organisms are emphasized by means of tables and algorithms.

Paralysis with Ixodes cornuatus envenomation.

Ixodes cornuatus is a tick that is widely distributed in Victoria, Tasmania and southern New South Wales. Serious human envenomation has not been reported previously. The clinical syndrome that results from envenomation by Ixodes cornuatus in a three-year-old boy is presented. Bulbar palsy and respiratory failure necessitated endotracheal intubation and mechanical ventilation for five days. Canine tick antivenom was administered.

Nonpolio causes of polio-like paralytic syndromes.

In a study of patients with suspected poliomyelitis, but from whom poliovirus was not isolated, a variety of causes of the paralysis was found. Injury of the spinal column sometimes followed by periostitis or osteomyelitis was relatively common. Exotic causes included paralysis due to snake bite, spider bite, scorpion sting, and tick bite and schistosomiasis involving the spinal cord. Chemical poisons, such as arsenic, triorthocresyl phosphate, and organophosphorus insecticides, were responsible for paralysis affecting groups of people. Paralysis in individual patients with porphyria followed the administration of anesthesia and certain drugs. Normal clinicopathologic findings in hospital nurses with Iceland disease suggested a psychological component. The Guillain-Barré syndrome in some patients resulted from virus infection of the nerve tissue, in others it was related to a hyperreactive autoallergic state. Enterovirus infections, especially coxsackieviruses A9 and A23 (echovirus 9) and group B coxsackieviruses, frequently caused meningoencephalitis often associated with transient paralysis. Coxsackievirus A7 infection occasionally resulted in permanent paralysis. Clearly it is important to maintain surveillance of these infections.

Tick paralysis in a western harvest mouse.

An engorging female Ixodes pacificus was observed on a western harvest mouse (Reithrodontomys megalotis) in Humboldt County, California. The mouse demonstrated a flaccid paraplegia, but it appeared to recover fully after the tick was removed.

Paralysis of calves by the tick, Ixodes Holocyclus.

Adult female Ixodes holocyclus were collected from the field at Fig Tree Pocket, a Brisbane suburb, at Tamborine Mountain, Queensland and at Lismore, New South Wales, in November 1974. Females were also reared from engorged nymphs collected off bandicoots from Tamborine Mountain July 1974 and 1975. In November 1974 unexposed 2-3 week old British breed calves, weighing between 26 and 46 kg were infested with 2,4,8 or 10 ticks. Neither 2 nor 4 females per calf caused paralysis. A challenge of 8 to 10 females induced paralysis 6 to 9 days after infestation by which time most ticks had engorged. There was little difference between ticks from different geographic localities. The site of attachment had no influence on tick toxicity. In September 1975, 2-3 week old British breed and Sahiwal x Jersey calves were infested with female ticks which had moulted 2-4 weeks prior to infestation. All but one calf with 10 ticks and all calves with 4 ticks became paralysed 8 to 13 days after infestation. At the time of paralysis only 1 of the 86 ticks had engorged and the remainder were small (30 to 50 mg). The greater toxicity of the latter ticks may have been due to the different treatment of ticks prior to infestation or to variations in the production of toxin associated with slow feeding. Four of 7 paralysed calves were saved using canine antitick serum.