You Don't Want Lepto, Your Dog Doesn't Either


March, 2005

There aren’t too many diseases that kill both people and dogs; leptosis is one of them.

There aren’t too many diseases that kill both people and dogs; leptospirosis is one of them. What’s more, this disease – which most people have never heard of and can barely pronounce – can potentially be passed from dogs to people.

“Based on various surveys, there is no doubt whatsoever that leptospirosis is under-diagnosed (in dogs),” says Dr. Larry Glickman, professor of epidemiology at Purdue University School of Veterinary Medicine, West Lafayette, IN..

Leptospirosis is a disease caused by spiral-shaped bacteria organisms, called spirochete found in the urine of infected animals. People and animals who happen to drink infected water become ill.

Glickman said that the results of one survey demonstrated that when dogs exhibited general symptoms possibly indicative of lepto, it turned out twenty to thirty per cent did indeed test positive for the disease.

“The problem is that most vets don’t necessarily test for this disease in the first place,” says Glickman. “They should, but the symptoms (for leptospirosis) are general; they just don’t have the mind set to think about leptospirosis.”

Those general symptoms in dogs may be liver and/or kidney values gradually falling out of whack, a fever, generalized depression, vomiting and lack of appetite. “The difficulty is that any combination of these symptoms might indicate any number of other illnesses,” says Atlanta, GA-based Dr. Stephen Jaffe, director field veterinary services Ft. Dodge Animal Health.

Lepto can diagnosed by a blood test. But what you think you see isn’t always what you get when it comes to lepto. Even though a positive blood test indicates a positive infection, an initial negative blood test doesn’t necessarily rule out leptospirosis.

“I can’t believe I hadn’t heard about this disease,” says Al Luhua, who lives in Waimea, Hawaii, a state where lepto is relatively common. His 4-year old German shepherd-mix was diagnosed last year. “I’m lucky, Ginger is just fine now. But I could have lost her.” Because he lives at a place where lepto occurs with some frequency, vets know to look for it, even if the pet’s owners have never heard of the disease, but that’s generally not the case elsewhere in America.

Of course, the best way to deal with leptospirosis is to avoid it in the first place. Ft. Dodge has manufactured a vaccine, which Jaffe maintains is new and improved. Jaffe says the vaccine is safe and will fight off various serovars or strains of the disease. Again, what you see isn’t always what you get with lepto. Because there are there are about 200 known serovars, treatment and/or diagnosis may be complicated when vets don’t know exactly which strain they’re dealing with.

For example, a strain of lepto, called grippotyphosa, was recently discovered in New York City, a place where you might not expect to find lepto in the first place. The Cornell University Diagnostic Laboratory and public health officials in the Big Apple have repeatedly expressed concern about the potential spread of the disease.

Raccoon, deer and all sorts of animals, including city rats – apparently a primarily transmitter in places like New York City – deliver the disease through their urine. So, it’s easy to understand how lepto occurs in dogs since they’re not always choosy about where they choose to drink.

Lepto is transmitted to people the same way as it is in dogs. Since people are more discerning about where they drink, you’d think lepto would be pretty much non-existent here. Not being a reportable disease, the Centers for Disease Control and Prevention (CDC) in Atlanta, GA say they don’t know for certain – but estimate 100 to 200 instances of lepto in people annually, with about half of those occurring in Hawaii. There are places in Hawaii where signs warn: ‘Lespospirosis: Don’t drink the water.”

The CDC calls leptospirosis the most widespread zoonotic disease in the world (that’s any disease that animals and people can pass to one another). According to the World Health Organization, following last year’s tsunami in Asia, leptospirosis was responsible for deaths throughout Indonesia, Sri Lanka, Thailand and India.

When lepto in people is diagnosed swiftly and treatment is appropriate, it is rarely fatal. However, diagnosis and treatment may not be so efficient in third world countries, particularly following disasters.

The disease is transmitted when people drink from, or even bathe or swim in water infected by wild and/domestic animals (and then accidentally take in small amounts of water).

While your own infected dog could transmit the disease to family members, Glickman says that’s not likely to happen. “Of course, vaccinating the dog is one way to alleviate any concern,” he says.

Those people most at risk may be veterinary professionals who deal with infected dogs, and certainly geography does play a role for people and pets.

In the U.S., Hawaii remains a hot bed for the disease, and, of course, dogs don’t read signs telling them not to doggy paddle in picturesque lagoons. But lepto occurs in the contiguous 48 states as well, particularly in pets.

Certainly, you might figure indoor/outdoor cats would be susceptible. It seems cats may be infected, and may possibly continue to spread the disease; however they don’t become ill. “All kinds of animals do get sick with lepto though,” says Glickman. who points out there’s currently an outbreak among California sea lions.

In the past, it was thought that climates with more rain and therefore more standing water would have the most lepto. Those climates remain places where lepto happens. However, Glickman’s soon to be published research demonstrates that where suburban sprawl intersects with forests – and their inhabitants – the disease is apparently on the rise. Farms have always been places where lepto occurs, and now – as confirmed by New York’s experiences – lepto has come to the big city.

All unvaccinated dogs are susceptible if they’re exposed to lepto. Of course, dogs who are outdoors more often, or who go camping or even to dog parks might be more prone. It seems small dogs who spend their lives in high rise condos are less at risk.

Glickman, says the vaccine is no more or less safe than most other canine vaccines. However, dogs under twenty pounds are more likely to have an adverse vaccine reaction. “The higher the dog’s weight, the lower the chance of a bad reaction to any vaccine,” Glickman says.

As with all vaccines, talk to your veterinarian about what’s right for your pets.