Lyme Disease in Dogs
Oliver Organista, LA Lyme disease is triggered by the bacterium Borrelia burgdorferi, which belongs to the spirochete class, characterized by its worm-like, spiral shape within the genus Borrelia. This bacterium is spread to both dogs and humans through the bite of an infected black legged tick, also known as the deer tick (Ixodes scapularis). The lifecycle of the I. scapularis tick occurs at various times throughout the year, influenced by geographic location, which in turn affects the timing of Lyme disease transmission. This disease is predominantly found in certain regions, including southern New England, the eastern Mid-Atlantic, the upper Midwest (notably Wisconsin and Minnesota), and parts of the West Coast such as northern California in the United States. Lyme disease is also encountered in Europe and Asia. Typical habitats for these ticks include forests, grassy areas, wooded and marshy zones near bodies of water, and secluded or rural parts of homes and buildings. In Canada, Lyme disease can be spread by two types of black legged ticks: Ixodes scapularis and Ixodes pacificus. Dogs are most often bitten by adult I. scapularis ticks, which are particularly active during the cooler months of early spring and late fall. It is rare for a female tick to pass B. burgdorferi directly to her offspring. Ticks generally acquire the infection during their juvenile stages after feeding on an infected wildlife host, typically rodents. Since ticks feed only once at each life stage, the bacterium’s next chance to spread occurs with the tick’s subsequent blood meal in its next developmental stage. Clinical symptoms Symptoms of Lyme disease typically emerge several months after infection, often between two to five months post-exposure. The clinical presentation of Lyme disease can closely resemble that of anaplasmosis, as both diseases share similar symptoms and occur in similar regions of the country. The most common indicators of Lyme disease in dogs include: Lameness: One of the hallmark signs of Lyme disease is the inability to properly use one or more limbs, often due to pain. Swollen lymph nodes: The swelling of lymph nodes, located in areas such as the neck, chest, armpits, groin, and behind the knees, often signals an immune response to the infection. Joint swelling: Dogs may show signs of swollen joints, which can lead to stiff movements or reluctance to be touched, indicative of discomfort. Fatigue: Affected dogs may display flu-like symptoms, including a noticeable decrease in energy and increased lethargy. Loss of appetite: A reduction in eating habits, particularly if it results in weight loss, can be a symptom of Lyme disease. Fever: A fever is another possible symptom that can accompany the other signs mentioned. In some uncommon instances, untreated Lyme disease can lead to serious complications involving the kidneys, nervous system, and heart. Kidney involvement is the second most frequent severe manifestation of Lyme disease in dogs and often proves to be fatal. Cases involving the nervous system may present with facial paralysis and seizures. Heart-related complications, while rarer, have also been documented. Diagnosis To diagnose Lyme disease in dogs, serologic assays are the most widely used methods. While some laboratories continue to utilize traditional approaches like the whole-cell enzyme-linked immunosorbent assay (ELISA) , the immunofluorescence assay (IFA), and rapid tests. These tests identify the presence of antibodies against specific proteins of B. burgdorferi, offering a simple yes/no result regarding the dog’s serology status. Treatment Treatment is advised for dogs that test positive for Lyme disease and show clinical symptoms, as well as for asymptomatic dogs that have signs of protein-losing nephropathy. The antibiotics doxycycline and minocycline are the primary medications used, administered at a dose of 10mg/kg orally every 12 to 24 hours for 30 days. Amoxicillin and erythromycin are alternative antibiotic options. Additionally, a non-steroidal anti-inflammatory drug (NSAID), such as carprofen or deracoxib, may be prescribed to manage symptoms. Prevention To safeguard against Lyme disease, the most effective approach is the consistent use of tick-prevention products throughout the year. There are numerous commercial options available for controlling ticks on both dogs and cats, such as systemic treatments (like isoxazolines), topical applications (such as permethrin and fipronil), and tick-preventive collars. Vaccination also serves as an effective means of protection. Additionally, limiting exposure to tick-infested areas and practicing caution in environments known to harbor ticks are important preventive strategies. References 2. Lyme Disease in Dogs: Signs and Prevention, Kathryn E. Reif, MSPH, PhD.,April 2020, https://todaysveterinarypractice.com/parasitology/lyme-disease/ 3. Lyme Disease, IPAC (https://ipac-canada.org/lyme-disease.php) 4. Littman MP, Gerber B, Goldstein RE, et al. ACVIM consensus update on Lyme borreliosis in dogs and cats. J Vet Intern Med 2018;32(3):887-903. 5. Mullegger RR. Dermatological manifestations of Lyme borreliosis. Eur J Dermatol. 2004 Sep-Oct;14(5):296-309. PMID: 15358567
Canine Lyme Disease
Oliver Organista, LA Lyme disease is a disease caused by the bacterium Borellia burdorgferi; a worm like, spiral-shape bacterium of spirochete class in the genus Borellia. The bacterium B. burgdorferi is transmitted through a bite of infected blacklegged tick or deer tick (Ixodes scapularis) to dogs and humans[1]. Different life-stage of I. scapularis ticks emerge at different times of the year (varies according to geographic location), giving a seasonality to Lyme disease transmission dynamics. It appears primarily in specific areas including the southern New England states; eastern Mid-Atlantic states; the upper Midwest, particularly Wisconsin and Minnesota; and on the West Coast, particularly northern California in the United States. It is also present in Europe and Asia[7]. Most of the areas where to find them are in forest or grassy, wooded, marshy areas near rivers, lakes or ocean, and are common in homes and buildings in secluded or rural areas. In Canada, there 2 types of blacklegged or deer tick that can spread Lyme disease. The blacklegged tick (Ixodes scapularis) and the blacklegged (Ixodes pacificus) [3] . Dogs tend to be bitten by infected I. scapularis adults, which are most active in the cooler early spring and late fall months [2]. An adult female tick is rarely (if ever) transmitted the B. burgdorferi to her offspring. Ticks most commonly become infected as juveniles after a bloodmeal on an infected wildlife host (most commonly rodents). Because ticks typically feed only one time per life stage, the next opportunity for B. burgdorferi transmission is during the next bloodmeal in the tick’s next life stage[2]. Typically, Lyme disease symptoms will take a couple of months or more to appear (2-5 months) after getting infected [8]. Symptomatically, Lyme disease can be difficult to distinguish from anaplasmosis because the signs of the diseases are very similar, and they occur in essentially the same areas of the country. Lyme disease is diagnosed through a blood test that shows whether an animal has been exposed to the bacterium[11]. Common symptoms that will appear are: Lameness: An inability to use one or more limbs is one of the most common symptoms of Lyme disease in dogs. Swollen lymph nodes: found in the neck, chest, armpits, groin, and behind the knees, are typically the first to show swelling. Lymph node swelling indicates an immune response triggered to fight the disease. Joint swelling: Swollen joints, stiff walking, or avoidance to touch may be other signs of the disease. Fatigue: Dogs with Lyme disease may also exhibit flu-like symptoms of low energy and lethargy. Loss of appetite: Losing interest in eating, especially if it leads to weight loss, is another sign that a dog may have Lyme. Fever: In addition to the above symptoms, a dog may have a fever caused by the Lyme disease infection. In rare cases, if Lyme disease is left untreated it can lead to damage in the kidneys, nervous system, and heart. Lyme disease affecting the kidneys is the second most common syndrome in dogs and is generally fatal. Facial paralysis and seizure disorders have been reported in the disease form affecting the nervous system. The form of the disease that affects the heart is rare. [10]. The most commonly used to diagnose Lyme disease in dogs are the serologic assays. Although some laboratories still use traditional serologic methods (e.g., whole-cell enzyme-linked immunosorbent assay and immunofluorescence assay), these assays have largely been replaced by serologic assays that detect host antibodies to specific B. burgdorferi proteins. These assays are qualitative, providing a yes/no answer regarding B. burgdorferi serostatus[3]. Treatment is generally recommended for seropositive dogs that display clinical signs of Lyme disease or are asymptomatic but have evidence of protein-losing nephropathy[4]. Most frequently antibiotics used to treat Lyme disease in dogs are doxyclycline and monicycline, at a dosage of 10mg/kg PO q12h to q24h for 30 days [2][5]. Amoxicillin and erythromycin are other antibiotics that can be used for treating the disease. A non-steroidal anti-inflammatory (carprofen or deracoxib) may also be given to the patient [6]. A possible complications may occur when treating Lyme disease. Some dogs who take antibiotics can develop loss of appetite, vomiting and diarrhea. Once infected, a dog will always have the bacteria that cause Lyme disease in his or her body. Therefore, relapses are possible; lookout for unexplained fever, swollen lymph nodes, and/or lameness. A small percentage of dogs develop kidney failure as a result of Lyme disease. Clinical signs include vomiting, weight loss, poor appetite, lethargy, increased thirst and urination, and abnormal accumulations of fluid within the body. [6] The best way to protect from Lyme disease is to use tick-preventive products year-round. Several safe and effective commercial parasiticides are available for tick control on dogs and cats, including systemics (isoxazolines), topicals (permethrin, fipronil), and collars. Another effective strategy is vaccination. Other prevention strategies include reducing exposure to ticks and avoiding areas with ticks [2]. References [1] Lyme Disease Diagnostic Market – Growth, Trends, COVID-19 Impact, and Forecasts (2022 – 2027), MOdor Intelligence, January 202 [2] Lyme Disease in Dogs: Signs and Prevention, Kathryn E. Reif, MSPH, PhD.,April 2020, https://todaysveterinarypractice.com/parasitology/lyme-disease/ [3] Lyme Disease, IPAC (https://ipac-canada.org/lyme-disease.php) [4] / Littman MP, Gerber B, Goldstein RE, et al. ACVIM consensus update on Lyme borreliosis in dogs and cats. J Vet Intern Med 2018;32(3):887-903. [5] Mullegger RR. Dermatological manifestations of Lyme borreliosis. Eur J Dermatol. 2004 Sep-Oct;14(5):296-309. PMID: 15358567 [6] How to Treat Lyme Disease in Dogs, Jennifer Coates, DVM, December 2014, PETMD (https://www.petmd.com) [7] Lebech AM. Polymerase chain reaction in diagnosis of Borrelia burgdorferi infections and studies on taxonomic classification. APMIS Suppl. 2002;(105):1-40. PMID: 11985118 [8] Could Your Dog Have Lyme Disease? How to Recognize the Symptoms and Get Treatment, Lavanya Sunkara , July 2022, GoodRx Health [9] Everything You Need To Know About Lyme Disease In Dogs, Kimberly Alt, July 2022, Canine Journal [10] Lyme Disease (Lyme Borreliosis) in Dogs, Reinhard K. Straubinger, DrMedVetHabil, PhD, Institute for Infectious Diseases and Zoonoses, Department of Veterinary Sciences, Faculty of Veterinary Medicine, LMU, October 2022 [11] Lyme disease: A pet owner’s guide, American Veterinary Medical Association
