Recently two dogs came to our clinic; one with very few symptoms, except relative lethargy (being a pug he did not run around and did not want to play as much), lack of appetite and slight signs of pale jaundice-colored gums.
The second dog was brought in severe shock, unable to walk, with severe jaundice, high temperature, having vomiting and diarrhea for 3 days. As with all cases that come to our clinic, the diagnosis is our absolute priority and so our team dived straight into blood work, stool samples, rapid tests, etc.
Eventually, both dogs tested positive for leptospirosis. Both passed away within 24 hours, even though the severity of the cases were very different – one mild and one severe – and the best medicines and supportive care was given to both continuously for 24 hours. And so, given the seriousness of the disease, its high mortality rates, and the fact that it is a zoonotic (which means that can easily be transmitted to humans through the contact with urine of infected animal) and thus, presents a huge hazard to humans and public health in Cambodia, I believe it is appropriate that we discuss it.
So, what is leptospirosis? In simple terms, leptospirosis is a bacterial infection that is commonly found in soil and water all over the world, although it tends thrive in warmer climates with higher annual rainfall. The World Health Organization (WHO) estimates that over one million human cases of leptospirosis are reported globally and there is strong evidence that this number is rapidly growing, with higher number of countries reporting leptospirosis outbreaks. I suspect, in developing countries, where medical care is limited, the rates are much higher and go undiagnosed most of the time.
For the real science buffs among my readers, here are some molecular biology study synapsis of the bacteria: according to Dr. Russell C. Jonhson,“Leptospira interrogans causes leptospirosis, a usually mild febrile illness that may result in liver or kidney failure. Leptospira enters the host through mucosa and broken skin, resulting in bacteremia. The spirochetes multiply in organs, most commonly the central nervous system, kidneys, and liver. They are cleared by the immune response from the blood and most tissues but persist and multiply for some time in the kidney tubules. Infective bacteria are shed in the urine.”
According to studies, some of them carried out in Southeast Asia, contamination with Leptospires of humans may be direct, via contact with urine or tissues from infected animals, or indirect, where freshwater or humid environments are contaminated with an infected animal’s urine.
While leptospirosis is the most prevalent bacterial zoonosis worldwide, “rodents are believed to be the main reservoirs of Leptospira”. Many studies on the subject suggest that the close proximity of human activities and rodent population increase the probability of contracting leptospirosis. In Southeast Asia, the risk of leptospiral transmission to humans is not limited only to wetlands and rice fields, but is also “linked to forested areas, and activities such as the hunting and/or preparation of rodents for consumption.”
As far as pets are concerned, dogs are reported to be more likely to be affected than cats. According to the American Veterinary Medical Association, the risk factors in dogs include exposure to or drinking from rivers, lakes or streams; exposure to wildlife and rodent-infested environments; farms and farm lands, and direct contact with rodents and infected dog urine. “Dogs can become infected and develop leptospirosis if their mucus membranes, skin with wounds, such as a cut or a scrape, come in contact with an infected animal or infected urine; by urine-contaminated soil, water, food or bedding; and by eating infected tissues and carcasses”.
In Cambodia, where the open sewage is a common and during heavy rains create the overflow of sewage into the streets; where rodent population is in high in both urban and rural areas, it is would be no surprise that leptospirosis is highly prevalent, but due to its wide variation of symptoms – from none at all to a kidney or liver failure, it goes misdiagnosed much too frequently.
Most commonly, the symptoms are high fever, jaundice (yellowing of the skin, gums, and mucous membranes), vomiting, diarrhea (often bloody), lethargy, loss of appetite, dehydration to name a few. But as said earlier, some dogs may present little to no symptoms and there are cases, where dogs resolve the disease on their own without any medical intervention, while others die suddenly, while also presenting no symptoms and diagnosed post-mortem. This is what makes this disease so difficult to diagnose.
So, as responsible pet owners, how do we recognize leptospirosis and most importantly, protect our dogs from contracting the illness in the first place? Early detection is the key to successful treatment outcome. If caught and treated early and aggressively, there are good chances of recovery, although many vets suggest that leptospirosis may leave its permanent damage on liver and kidney functions of the animal.
My advice to those living in Cambodia with their pets, both in urban and rural areas, are the following:
1. Make absolute sure that your dog is vaccinated against leptospirosis. Cambodia is by all means is a high-risk area and thus, annual vaccination is a key.
2. When you walk your dog, ensure that s/he is not off the leash and never allow them to pick up dead animals, sniffing dead rodents or even worse, chase rodents and kill them (thus, being in direct contact with potential disease carrier).
3. Ensure that the rodent population in your garden/property is always under control.
4. Do not let your dog/s eat rats and needless to say, please do not eat them either.
5. If you catch your dog with a rat or suspect direct contact with a rat or rat urine, infected animal, and wildlife, observe your dog carefully for at least 24 hours and seek veterinary help if you see any signs of illness.
6. Avoid lakes and stale waters and, unfortunately rivers. As much as our dogs might love swimming, given the current poor natural water conditions, pollution, sewage system (or lack thereof), and poor sanitation, none of the natural water reservoirs are safe for them (or us).
7. If your dog loves to swim, I suggest you get a small pool, sold in any kids’ shops to give you animal a chance to frolic and yet, making sure the water is clean.
8. Take extra precaution with choosing your walking paths during the monsoon seasons. As water levels are rising, sewages break into the streets and contamination is highly likely. I would suggest to avoid the high-risk areas altogether.
And finally, I cannot stress enough, proper hygiene is of utmost importance for you and your dog. While direct dog-to-human transmission is highly unlikely, nonetheless, if your dog has been diagnosed with leptospirosis, please ensure you seek medical advice for yourself and everyone who have been in contact with your sick pet.
Stay safe for 2019.
Animal Mama® Animal Clinic & Welfare Centre provides a wide range of services for animals & pets: vet care, boarding, daycare, pet food & supplies, hydrotherapy, grooming and doggy play dates.
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Villa #15, Street 500
Toul Tom Pong, Phnom Penh 12311