Spring is Here!

by Joshua Bub, DVM

The weather is getting warmer, the snow is melting, and the days are getting longer; there’s no doubt that spring is here!  It’s a great time of year to get outside with your pet and enjoy all that Colorado has to offer.  However, with the warmer weather comes a new set of risks for your pet; heartworm disease, leptospirosis, and rattlesnakes to name a few.  I’m writing today to help increase awareness about some of these risks, and provide tips to help your pet stay healthy this season!

Rattlesnakes – In the West Denver area, we see the majority of snake bites occurring on Green Mountain and the Table Mesas, although they can occur anywhere.  There’s very little to know about rattlesnake bites other than – 1. keep your dog on a leash in areas where rattlesnakes may be present, and 2. If your dog is bitten, get to a veterinary hospital immediately.  There’s a saying that goes, “for a snake bite, the most effective first aid kit is a set of car keys and directions to the hospital.”  On route to the veterinary hospital, it is helpful to keep the area that was bitten below the heart, and take necessary steps to keep your dog calm and therefore keep his or her heart rate low to slow the spread of venom.  Rattlesnake bites cause severe swelling, pain, and tissue necrosis in the area that was bitten.  With proper treatment, few animals die from a bite, although there is usually an extensive hospital stay involved to manage pain and swelling, and prevent complications such as infection, blood clotting disorders, and heart problems.  Antivenin can be given within the first few hours after being bitten and can reduce the damage caused by envenomation.

Heartworm disease – Heartworm disease is spread by mosquitos who are infested with the larval stages of heartworm.   When they bite your dog (or less commonly, your cat), the microscopic heartworm larvae are deposited under your dog’s (or cat’s) skin and spend a few months migrating through the body and end up fully mature in the heart after 5-6 months.  Once there, the inflammation caused by the adult worms (which can grow up to a foot in length!) leads to significant lung disease.  Once a dog is infected, treatment is with a series of painful (and expensive) injections which kill the adult worms.  During the treatment and for 1 month afterwards, a treated dog needs to be confined in a crate to prevent the heart rate from elevating, which may dislodge the dying worms and kill the dog.  At the time of this writing, these injections are in very short supply, and are nearly impossible to find.  There is no curative treatment for infected cats.

Luckily, prevention of this disease is simple and involves a once monthly oral medication that kills any immature heartworm larvae that have entered your dog’s system.  This medication needs to be given once monthly as the heartworm larvae become immune to the drug after developing for about 45 days.  The medication also kills any roundworms or hookworms in the intestinal tract.  We’re fortunate in Colorado that heartworm disease hasn’t taken hold as strongly as in other areas of the country due to our light mosquito population, however it is still here.  At Mesa, we recommend starting heartworm prevention on June 1st, and giving it once monthly for 6 months.  A heartworm test is required once yearly to check for heartworm infection to make sure your pet hasn’t acquired infection in the off months or during a lapse in treatment.

Leptospirosis – Leptospirosis is a frightening disease.  It is caused by an organism found in the urine of wild animals and can affect your pet if he or she drinks from contaminated water, eats or gets bitten by an affected animal, or even comes in contact with soil where an infected animal has recently urinated.  Leptospirosis is more common in the warmer, wetter months – usually late summer to early fall. Dogs are more susceptible than cats, and if infected they will enter acute kidney failure and liver failure.    If infected, your dog can transmit the organism to you through contact with his or her urine.  Leptospirosis causes illness in humans ranging from flu-like symptoms (in 90% of people), to kidney failure, liver failure, or meningitis (in 10% of people).

Leptospirosis is increasing in incidence in Colorado; at Mesa we routinely see at least a few cases per year.  We consider every dog at risk, even if you live in downtown Denver and your pet only goes in your yard there are usually raccoons and squirrels present who can carry the disease.  Apart from not letting your pet drink stagnant water, there is little you can do to avoid the organism, the most effective method of prevention is vaccination.  The leptospirosis vaccine is given once yearly (a series of two vaccines is needed if your dog has never had the vaccine before), and it is given at a different date than other vaccines to minimize the chance of a vaccine reaction.

Intestinal parasites – With warmer weather comes more active pets and more active wildlife, and the potential for transmission of intestinal parasites increases.  The majority of intestinal worms (hookworms, roundworms) are transmitted through the fecal-oral route in dogs and cats.  These worms are usually not noticeable by pet owners since they live exclusively in the GI tract, and the only way they are detected is through yearly fecal tests.   The reason we get worked up about intestinal parasites is because of the risk they present to people.  Roundworm infestation in people can cause severe organ damage and blindness, hookworm infestation can cause extremely itching skin disease.   Luckily, prevention is as simple as giving your pet his or her once monthly heartworm preventative.

Tapeworms also live in the GI tract, and spread by breaking off small parts of their body which are defecated by the dog or cat and appear as small white “grains of rice” on the rectum; these are the most common worm that pet owners report.  They are generally spread by fleas or rodents, and treatment is with a single dose of a parasiticide as well as eliminating the source of infestation.

Ticks – The main concern with ticks is not the bug itself, but the diseases they can transmit.  Tick-borne disease can cause any number of signs from fever and lethargy to lameness and organ damage.  Ticks are most active during late Spring and early Summer, before it gets too hot outside.  If you go hiking or visit the mountains with your pet during this time of year, he or she will almost certainly be exposed to ticks.  There are multiple topical medications that can be effective, contact us to discuss the pros and cons of each preventative.

The best way to keep your pet healthy is through preventative medicine, and many of these risks can be easily prevented with a bit of knowledge and a bit of medication.  As always, our veterinarians are just a phone call away to discuss any of these issues and how they may relate to your pet!