Leptospirosis

Leptospirosis is a highly contagious disease both to humans and animals. Rats are known to be the carriers of the bacteria. Dogs are infected by ingesting food contaminated with rat feces or urine and by direct contact with other infected animals. Symptoms of the disease are usually seen one week after the dog has been infected. Aside from dogs being less appetent and less active, the most common clinical signs seen are vomiting, diarrhea (with or without blood), and in severe cases – yellowing of the skin and the sclera.

Certain laboratory tests such as complete blood count, liver and kidney enzyme tests and sometimes EDISA are done to diagnose leptospirosis. Complete blood count will help the veterinarian to gauge the body condition of the dog, it also helps narrow down the possible diseases producing the same clinical signs. In some cases, results from the complete blood count is not enough to make a full diagnosis—during this time ELISA is of great aid. ELISA (enzyme linked immunosorbent assay) is the laboratory test that detects antibodies against the bacteria, this can also differentiate an active infection from a vaccine produced antibodies. Results made by ELISA are considered gold standard with little false negative probability. When Leptosirosis has already been confirmed the next question a veterinarian should ask is the extent of damage the bacteria had done to the body. The bacteria damages the liver and in advanced cases the kidneys as well, enzyme tests (ALT,AST, BUN, CREA, etc) help determine the state of these organs.

Fluid therapy has two importance: the first one is to prevent the animal from being dehydrated and the second one is to ensure that the kidneys are still functioning well. Treatment of leptospirosis is not an easy task--- usually the dog dies due to liver or kidney damage or both. Combined penicillin and streptomycin is the treatment of choice against the bacteria. Encephalopathies caused by these damages must be guarded against. Symptomatic treatments like anti-emetics, anti-pyretics, vitamins and liver tonics are also given to help prevent liver complications and make the animal comfortable. Unfortunately, when the bacteria reaches the kidneys and does extensive damage, the disease becomes harder to treat. The kidney is a very important organ when it comes to excreting toxins out of the body. When they are damaged toxins tend to build up in the blood stream. Polluted blood circulates around the body ergo producing more damage to the brain and other vital organs. Lactulose and metronidazole are sometimes helpful to cease the build up of ammonia and other toxin producing bacteria. A wide array of medicines can be used as supportive therapy to patients infected with leptospirosis. But the recovery greatly depends on the animal’s immune system.

The spread of the disease can be stopped by disinfecting the surrounding once a day when there is active infection or once a weak in endemic areas ( especially during the rainy season). Chlorine has proved to be effective in eliminating the bacteria from the environment. At least, 2 tablespoons of chlorine are mixed in half bucket of water. The mixture can be sprayed onto the environment. Be sure to do this during the hottest part of the day to facilitate rapid evaporation of the chemical and prevent possible poisoning of your pets. Leptospirosis can infect all ages--- this is why infected dogs should immediately be separated from healthy dogs. In cases when a household has several other dogs but does not show symptoms yet, the uninfected dogs are given prophylaxis to prevent them from getting infected. Family members should always handle infected dogs with caution. Thorough washing of hands is a must to prevent zoonosis ( transfer of the disease from the animals to humans). Wearing of gloves is recommended especially when cleaning dog urine and feces.

Prevention is still better than cure --- leptospirosis can be prevented by vaccination. The vaccine can be administered at 6 -16 weeks of age with 2-3 weeks intervals. But because the disease is bacterial in nature, the protection given by vaccination only lasts 6 months, thus it is recommended that pets should be given booster shots every 6 months (in endemic areas) or during rainy seasons.

Written by:
May Valera, DVM