Leptospirosis made the news last week when the New York City Department of Health and Mental Hygiene reported a cluster of three human cases had been identified in the Bronx. One infection was fatal. In the case of the Bronx residents, the specific type of Leptospira typically occurs in rats and a rat infestation is believed to be the source of these infections.
Leptospirosis was again in the news further from home when the Arizona Department of Agriculture warned dog owners about leptospirosis circulating in the Scottsdale Valley area. Typically, Arizona officials identify four cases of canine leptospirosis annually, but the warning was provoked by a number of confirmed cases 10 times the norm. The source of the infection in Arizona dogs has not been pinpointed, but officials warn dog owners to exercise caution in areas with damp soil and in dog parks.

This News is Not Fake

These two news reports illustrate several features of leptospirosis. First, the Leptospira bacteria is hearty, survives in many climates, and thus is a worldwide concern. The bacteria can infect multiple species including humans, dogs and other mammals. Although one news article last week was entitled “Rat-spread disease,” many animals, including rats, raccoons, deer, dogs and humans, can spread the disease in their urine. If urine containing Leptospira bacteria contaminates food or water, the bacteria can be transmitted when the food or water is consumed.

Clinical Signs of Leptospirosis

Diagnosis of canine leptospirosis can be challenging, since dogs infected with the Leptospira organism have vague clinical signs. Most dogs have no signs at all. Lethargy, weakness, poor appetite, vomiting and increased water consumption top the list in dogs with clinical signs. Routine blood tests show an elevated white count, abnormal liver tests and evidence of acute kidney injury. Specialized testing for leptospirosis is available and is required to confirm the diagnosis.

Dog Owner Action Steps

• Call your veterinarian and be sure your dog is up to date on his leptospirosis vaccination.
• Keep your dog out of areas with standing water which may harbor the Leptospira bacteria.
• Avoid walking your dog in areas frequented by wildlife and don’t attract wildlife to your property by providing them with food.
• If your dog is sick, see your veterinarian immediately because early diagnosis and treatment with appropriate antibiotics can cure leptospirosis.
• Tell your veterinarian if you dog has been in areas where Leptospira organisms could be hiding.