● Tick antiserum (TAS, tick antivenom, tick antitoxin) Immunity to tick neurotoxins, after being exposed in the past, or natural immunity has been described in dogs that have survived tick paralysis; however, natural immunity does not last long. The dog can develop tick paralysis after another tick bite. (Lundgren, 2016) Tick antiserum is commercially available in Australia for the treatment of tick paralysis. It is derived from hyperimmune dogs. However, TAS administration is Lyme disease (Lyme Borreliosis) Lyme disease is caused by the spirochete bacteria Borrelia burgdorferi . It is the most common vector-borne disease of canines and humans in North America. (Marconi et. al., 2020) This disease is endemic to temperate areas in the northern hemisphere and is seen sporadically in Europe and Asia. Within the USA, endemic areas include the Northeast (particularly the New England states), the upper Midwest, and the Pacific coast. Ixodes scapularis (deer tick) is the predominant vector in the Northeast and Midwest, whereas I. pacificus is the predominant vector on the Pacific coast. (Vogt, 2021) The possibility of a tick bite is at its highest from early spring to autumn, as ticks are most active during this time. Transmission When the immature life stages (larva and nymph) of blacklegged ticks feed on the blood of infected wildlife, they become infected with Borrelia . The bacteria persist through each molt of the tick, persisting throughout their next life stages. Infected nymph or adult female ticks can transmit the Borrelia when they feed on an animal or human host for at least 24-48 hours. (American Veterinary Medical Association, n.d.) At least 24 hours are required for the transmission of spirochetes from the infected tick into the host. Transmission usually occurs 36–48 hours into the blood meal. Early removal of attached ticks, therefore, reduces the likelihood of spirochete transmission. (Vogt, 2021) Rates of transmission are highest in the late spring, when nymphs and adult ticks are feeding, and in the fall, when adult ticks are feeding. (Straubinger, 2018) However, transmission is also possible during the winter, because ticks may be active as long as temperatures are >4°C (40°F). (Vogt, 2021) Lyme disease cannot be spread directly among dogs and people. (American Veterinary Medical Because the majority of infected dogs (95%) show no clinical signs, bacteria can often spread to other tissues and cause more severe manifestations, such as polyarthritis, transient fever, anorexia, lethargy, neurological dysfunctions, and/ or lymphadenopathy, particularly in the prescapular or popliteal nodes. (Milkovičová, 2023) Association, n.d.) Clinical findings Arthritis is the most common syndrome, affecting one to a few joints, particularly the carpal joints, with or without swelling, causing lameness or shifting leg. Chronically infected dogs may develop serious Lyme nephritis, associated with rapidly progressive glomerulonephritis. Lyme borreliosis symptoms in dogs are mostly manifested as an acute monoarticular or polyarticular lameness with joint swelling, fever, lethargy, and mild local lymphadenopathy, usually in young, often large breed dogs with an active/ outdoor lifestyle. (Milkovičová, 2023) Diagnosis As most dogs do not develop clinical illness after being infected, diagnosis can be challenging. The diagnosis of canine borreliosis is based on the epidemiological
not without the risk of drug reactions, so pros and cons should be weighed carefully before treatment. ● Supportive care : Paralyzed patients will benefit from supportive care that includes IV therapy, urinary bladder management, physiotherapy, and handfeeding. In some cases, a feeding tube may be considered. Antibiotics may be necessary as well as eye lubricants. The conscientious use of tick control products is the best way to protect dogs from tick paralysis. case history, duration of tick exposure, compatible clinical symptoms, exclusion of other diseases, response to antibiotics, and laboratory evidence of infection. (Milkovičová, 2023) In dogs, the characteristic presentation includes an intermittent, shifting lameness. (Vogt, 2021) Laboratory diagnostic techniques include culturing, histological examination of thin sections, serological tests, and polymerase chain reaction (PCR). As Borrelia spp . cannot be identified by standard optical microscopy or by Gram staining, dark-field microscopy or phase-contrast microscopy have become more accurate methods in routine diagnostics (Milkovičová, 2023): ● Indirect immunofluorescence assay (IFA)-testing for Borrelia-specific immunoglobulins M (IgM) detectable within 7 days of infection and immunoglobulins G (IgG) in a few days later. Limitations such as low specificity and cross-reactivity of the antibodies with other antigens, like heat-shock proteins and flagellar antigens, often lead to false-positive results. Very low sensitivity and specificity should not be recommended for screening purposes. ● ELISA test ● PCR has a higher diagnostic sensitivity comparable to that of culture in tissues. ● Metabolomics involves the quantitative detection of multiple small molecule metabolites in biological fluids, cells and tissues, which provides an efficient method for monitoring altered biochemistry that is closely related to the current disease or therapeutic status. Prevention and treatment Along with prevention, early diagnosis and treatment with antibiotics appear to be important to treatment success. (Vogt, 2021) Treatment of LB is based on treating spirochetal infection and managing pain of Lyme arthritis. Borrelia organisms are sensitive to tetracyclines, penicillin, macrolides, and cephalosporins. They are used during the early and late stages of the disease and may be given orally or intravenously. Beta-lactams and tetracyclines are also effective against Lyme disease and are widely used in veterinary medicine. Doxycycline is the first choice for most sick dogs with suspected LB and is recommended due to its easier administration and efficacy against coinfections. However, some veterinarians in the field prefer amoxicillin for doxycycline-sensitive or growing dogs. In case of tetracycline intolerance, other classes of antispirochetal antibiotics can be given. The most effective antibiotic classes for the supportive therapy of dogs are beta-lactams and tetracyclines with a long treatment course (4 weeks) due to the protracted biological behavior of Borrelia. (Milkovičová, 2023) A critical factor of successful treatment is its initiation; therefore, it should start as soon as possible with a focus on suppressing infection and pain.
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