LEPTOSPIROSIS A Modern-Day Threat by Beverley Cross
		It’s time to start using the 8-way vaccinations on your litters again, and if your adult hounds haven’t had a Lepto shot in a while, give them one, or have your veterinarian give them one, too. Leptospirosis has reared it’s ugly head pretty much all over the country (it used to be more prevalent in the northeast and south in marshy areas.) This is a nasty disease which left untreated or undiagnosed, could mean the difference between life or death in your dogs. It’s important that you not only vaccinate for it, but keep alert for the signs and symptoms.
	Leptospirosis is a bacterial disease caused by pathogenic members of the Genus Leptospira. This disease occurs worldwide in many animals, including our dogs. The canine disease presents as an acute infection of the kidney and liver and sometimes as a septicemia, (or better known as blood poisoning). Because many aspects of the infection are poorly understood, there is the possibility that the disease in dogs may go undiagnosed.  While diagnostic methods have improved over the years, most are relatively insensitive. This re-emerging infection is most likely influenced by the cycles of infection in wildlife, where the infection may be transmitted to domestic animals. Chronic kidney disease commonly follows infection, and abortions may occur in pregnant dams. Due to recent trends and events in the Northeastern states, leptospirosis has become suspect of differential diagnoses for dogs that are seen for acute liver and/or kidney disease. Other factors that may affect the pattern of disease in dogs are the vaccination history and the use of antibiotics. Common clinical signs reported in dogs include fever, vomiting, abdominal pain, diarrhea, refusal to eat, severe weakness and depression, stiffness, severe muscle pain, or inability to carry puppies to term. Generally younger animals are more seriously affected than older animals. Leptospira do not multiply outside of the host and their survival depends on environmental conditions in which leptospirae are found, e.g., soil and water conditions. Leptospira organisms can survive up to 180 days in wet soil, for many months in surface water and survive better in stagnant rather than free-flowing water. The source of infection to animals is either by direct contact with infected urine, fetal and placental material or fluids, uterine discharges, or indirect contact from a contaminated environment. A higher incidence of disease is more likely in soils with an alkaline pH, during the wet season (high rainfall areas), in low lying areas susceptible to run off conditions during rains, warm and humid climates, areas with an abundance of surface water resulting in marshy fields and muddy areas. Although dogs in fenced yards may be exposed to urine from wildlife, (including rodents) dogs such as hunting and show breeds, and all those with access to ponds or slow-moving streams are at greater risk than housedogs.
						Once leptospires penetrates the mucus membranes or intact or abraded skin, organisms rapidly invade the bloodstream over the next 4 to 11 days, creating a leptospiremia. In susceptible dogs, leptospires usually establish a septicemia and spread systemically to the internal organs, including the liver and kidneys, or to the placenta and fetus of the pregnant dam. If a dog had been vaccinated, it still may have antibodies, or it may mount an anamnestic (or recalled) response in the absence of antibodies. Young dogs who are unvaccinated, or whose dams were not vaccinated, are obviously at greater risk of severe disease and death that may occur due to an acute septicemia or hemolytic anemia (destruction of red blood cells). Previously vaccinated older dogs who, later, become infected naturally with a field strain similar to the vaccine given at an early age generally have minimal clinical signs. The treatment goals for acute cases of canine leptospirosis are to control the infection in the liver and kidneys before irreparable damage is done, and to suppress the leptospiruria. Severely ill, acute cases require a high degree of supportive care for survival and the immediate administration of fluids is essential. The prognosis is guarded for patients with acute renal failure and/or liver disease. Vaccination is especially recommended in endemic areas. Dogs usually recover after 2 weeks, if treated promptly with antibiotics and intravenous fluids, however, if kidney or liver involvement is severe, the infection may be fatal. Owners should be advised that leptospirosis is a zoonotic disease that can be spread to humans and is spread mainly by the urine of infected dogs. An infected dog’s housing and outside areas need to be thoroughly disinfected. Optimum prevention of contact would be vaccination, avoiding muddy, stagnant water (not always practical for the hunting beagle) and rodents. Needless to say, rodent control is a must and it is not wise to allow dogs to eat dead animals of any kind in the field.  Always consult your veterinarian if your dog presents any of the symptoms mentioned in this article.