Heartworm disease is a serious and potentially fatal disease in dogs (and less often, cats.) Heartworm disease is transmitted by mosquitoes. The mosquito bites an infected dog and ingests a small amount of infected blood while feeding. The infected blood contains the larval stage of the heartworm- a microfilaria. The microfilaria enter the pet’s bloodstream, travel through the bloodstream, growing as they mature. Within a few months time, the microfilaria become adult heartworms and reach the heart where they begin to reproduce.

Adult worms cause disease by clogging the heart and major blood vessels leading from the heart. They interfere with the valve action in the heart. By clogging the main blood vessels, the blood supply to other organs of the body is reduced, particularly to the lungs, liver, and kidneys, leading to malfunction of these organs.

The most obvious signs of infection are a dry cough, shortness of breath, weakness and loss of stamina. All of these signs are most noticeable after exercise when some dogs may even faint. A dog may also have weight loss, poor coat condition, and anemia. Severely infected dogs may die suddenly during exercise or excitement.

Microfilaria (young worms) circulate throughout the body but remain primarily in the small blood vessels. Because they are as wide as the small vessels, they may block the flow of blood. The body cells being supplied by these vessels (particularly the lungs and liver) are deprived of the nutrients and oxygen normally supplied by the blood.

(see chart below)

Destruction of lung tissue can lead to coughing. Cirrhosis of the liver causes jaundice and general weakness because this organ is essential in maintaining a healthy animal. The kidneys may also be affected and allow toxins to accumulate in the body.

In most cases diagnosis of heartworm infection can be made by a simple blood test that can be run at our hospital. Further diagnostics, such as blood chemistries, urinalysis, radiographs (x-rays), or an echocardiogram (ultrasound) of the heart are necessary to determine if the dog can tolerate heartworm treatment.

With heartworm treatment, there is some risk, although fatalities rarely occur. Heartworm disease can be treated successfully in more than 95% of patients, with the newer drugs on the market. In some situations of advanced disease, it is often safer to treat the organ damage, rather than risk treatment to kill the worms. Dogs in this condition are not likely to live more than a few weeks or months.

While heartworm disease can be devastating to the body and potentially fatal to your pet, it is also completely preventable. We highly recommend yearly testing and yearround heartworm prevention for your dog. Heartworm disease is much easier to prevent than to treat.

Cats are also susceptible heartworm infection. Outdoor cats are more likely to become infected than indoor cats, but cats are not the natural host for heartworm infection. Therefore, we see a drastically lower incidence of heartworm disease in cats than dogs. What this means is that while a cat may become infected through a mosquito bite, they are less likely to develop disease. The cat is unable to provide the ideal environment for the development of the heartworm larvae into the adult worm. If cats do develop heartworm infection, there is generally a small number of adult worms that survive in the heart; there is usually only 1 adult worm. For this reason, it can be very challenging to diagnose heartworm disease in cats. Because there is such a low incidence of heartworm disease in cats and because they are not the natural host for the parasite, we do not recommend preventative for cats.

Due to the dry climate of Colorado, there is not a high incidence of fleas in this area. However, wildlife, such as prairie dogs, rabbits, foxes, raccoons, squirrels, and birds are natural hosts for fleas and ticks and can bring these annoying pests closer to home than most of us would like to realize. Fleas are not only annoying to your pets, but if ingested they can cause tapeworms. And some pets even have allergies to flea saliva causing allergic reactions. Understanding the flea life cycle and how to prevent and/or control flea infestations are important to keeping your pet and home flea-free!

Although the adult fleas are visible, they are small and move quickly. If you see adult fleas on your pet, most likely there are more hiding elsewhere. One adult flea can lay up to 50 eggs on your pet per day! And it only takes 3-4 weeks for those eggs to hatch and mature into reproducing adults that can continue this process. Not all flea preventatives work the same way or include ingredients to kill all the stages of the flea life cycle. By understanding the flea life cycle you can choose the proper product to prevent or control potential flea infestations.

Fleas can infest your yard either by falling off their old host or by the flea eggs, that have fallen off the host, hatching. Because fleas feed on blood, they will seek out a new host (your pet) as soon as possible. Within 2 days, adult fleas will begin laying eggs. Most eggs fall out of the coat and accumulate where your pet frequents (bedding, carpet, and vacuum cleaner bag after the carpet has been swept).

Larvae hatch from the eggs after 4 days and go through 2 molts. After week 3, the larvae spin a cocoon and begin to pupate. At week 3-4, the adult fleas emerge from the pupa and begin looking for a suitable host.

Not all flea products are created equal, nor are most products suitable for both dogs and cats. Some products only kill adult fleas, some only kill flea eggs, some are not waterproof, and some are unsafe if touched by humans. Please read the product label carefully before choosing your flea prevention/treatment.

Paws of the Rockies recommends Frontline Plus to control flea and ticks. Frontline Plus kills adult fleas, flea eggs, and flea larvae for up to 3 months. Frontline Plus is an oil that is applied to the skin (by parting the hair on the pet’s back). It is absorbed and quickly spreads over the entire body via the oil (sebaceous) glands in the skin. From the sebaceous glands, the medication is continually replenished onto the skin and hair. It is this process that makes Frontline Plus truly waterproof. When the flea or tick comes in contact with the hair, it begins to die. Thus, the flea or tick does not need to bite your pet for the Frontline to work.

In order to eradicate an existing flea problem, it is important to clean the pet’s environment on a regular basis. To eliminate the flea eggs that may have fallen off your pet, you should wash all bedding the pet is in contact with, vacuum the carpets, and empty the vacuum bag. This will only eliminate the eggs that have been laid up until that point. Flea larvae and pupae are very sticky and will remain in the environment. Thus, more adult fleas may hatch during the treatment period. This part of the life cycle is why Frontline Plus should be used for at least 3 consecutive months if a flea infestation is already present. It is also important to treat all pets in the household, even if you do not see fleas on them. If not, any of the other animals can become a suitable host, allowing the flea life cycle to continue.

As you can see, once an infestation has occurred, it is timely and costly to treat. The best way to get rid of fleas is to prevent a problem in the first place. Flea eggs require temperatures between 55-89 degrees with 50-92% relative humidity for 14 consecutive days in order to hatch. The Colorado environment does not always provide these ideal conditions, but your home, boarding or grooming facility, or doggy day-care may! Call today to reserve your box of Frontline Plus.

Canine Influenza (H3N8) was first diagnosed in 2003. It is a highly contagious viral infection spread by aerosolized respiratory secretions and contact with contaminated objects. These objects could be kennel surfaces, food and water bowls, collars, leashes, toys, hands, and clothing. The virus is viable on surfaces for up to 48 hrs, on clothing for 24 hours, and on hands for 12 hours. The incubation period, which is the time from exposure to the virus to the onset of clinical symptoms, is typically 2-4 days. Dogs are most contagious during this 2-4 day incubation period when they are not exhibiting signs of illness. Virus shedding may continue 7-10 days.

Virtually all dogs that are exposed to H3N8 become infected with the virus. Approximately 80% develop clinical signs of disease, while the other 20% that do not exhibit clinical signs may still shed the virus and spread infection. Symptoms of canine influenza consist of: severe coughing, eye and/or nasal discharge, sneezing, depression, difficulty breathing, and fever.

Because symptoms of canine influenza are similar to many other respiratory conditions, diagnosis cannot be made from the symptoms alone. Available testing includes: nasal or pharyngeal swabs during the first 4 days of illness, antibody testing after 7 days of clinical illness, or blood serum collection during peak symptoms and again after symptoms resolve.

If blood is not taken while symptoms are present, antibodies can still be identified to tell whether the dog has been exposed to the virus.

Treatment for canine influenza includes supportive care based on clinical symptoms. Antibiotics are typically prescribed for secondary infections to the nasal pathways. Most dogs recover from illness within 2-3 weeks. Mortality rate is thought to be 1-5%, mainly among the immune compromised dogs.

Prevention includes washing hands after handling other dogs, dog supplies, or dog poop to prevent viral spread. If your dog is coughing or exhibiting any signs of illness, it is advised to isolate your dog from other dogs to prevent potential spread of infection. A canine influenza vaccine is now available to help control the spread of the disease.

The canine influenza vaccine is available through Schering Plough on a conditional license by the USDA. This means that data from the 700 dogs in the test study supported a reasonable efficacy. There were no reactions reported in this study but there are no long-term studies at this time. Initially, a series of 2 vaccines should be given, approximately 2-4 weeks apart. Annual revaccination is recommended thereafter.

The vaccine was created to aid in the control of canine influenza. Although the vaccine may not prevent infection altogether, it will reduce the severity and duration of clinical illness, reduce the amount of virus shed as well as shorten the shedding interval. Therefore, dogs that are vaccinated may still become infected with canine influenza, but are less likely to develop severe illness or spread the virus to other dogs. These benefits are similar to those provided by the influenza vaccine for humans.

Please contact Paws of the Rockies if you would like to schedule your dog to get the canine influenza vaccine.