Prior to 1989, heartworm disease was not a problem in Utah.  At that time, cases began to be reported along the Wasatch Front, and there have been dozens of reports since then.  This number has increased every year, and we expect the trend to continue.

How do Heartworms Affect My Dog?

Adult heartworms live in the right side of the heart and in the main blood vessels leading to the lungs.  Their accumulation impairs blood circulation, which causes damage to the dog's heart, lungs, liver and kidneys.  Unfortunately, a great deal of damage can occur before any outward signs of heartworm disease are noticed. 

 Symptoms include:

• Reduced Endurance
• Frequent Coughing
• Listlessness
• Labored Breathing
• Weight Loss

Without treatment, the disease leads to congestive heart failure and death.

How is Heartworm Disease Spread?

Heartworms are spread by mosquitoes, and are therefore more common in areas where mosquitoes are numerous.  Outdoor  dogs, which are constantly exposed to mosquitoes during the warmer months, are the most frequent victims.  When a mosquito bites an infected dog, the blood it takes contains microscopic, immature forms of the heartworms, which develop into infective larvae in the mosquito's body.  When the mosquito bites another dog, these infective larvae are then transmitted to that dog.  They migrate to the dog's heart and develop into adult heartworms if the dog is not on preventive medication.

What if I Travel with My Dog?

Heartworm is a very serious problem in other areas of the country, so prevention is especially important if you travel with your dog. Your dog can be tested and placed on preventive medication, both during the trip and for two months following your return.  It is important to continue prevention beyond the actual time of travel, in order to destroy any infective larvae that may have developed after your return.  Remember, heartworm was originally brought into Utah from other areas.  Protect your pets. Contact your veterinarioan before you go, to discuss your travel concerns

How Can I Tell if My Dog Has Heartworm Disease?

Most dogs with heartworm do not show symptoms.  However, your veterinarian can accurately diagnose this through the use of blood testing.  Dogs showing clinical signs may need x-rays and other lab testing.

Can Infected Dogs Be Treated?

Most dogs can be successfully treated for heartworms if the disease is detected early.  Blood tests are usually run before treatment begins, to detect underlying disease, and treatment can be modified as needed to minimize risks.  A series of carefully monitored, intravenous injections kills the adult heartworms.  After all the adult heartworms have been eliminated, a second medication is administered to destroy any immature heartworms or larvae in the bloodstream.

Prevention is Best!

Treatment of heartworm disease is an option.  However, prevention is far safer, less complicated, and less traumatic for your dog.  Preventive medication effectively kill the infective larvae before they can develop into adult heartworms.  Dog owners can choose between a monthly or a daily pill, which is given during the mosquito season and for two months after.  However, dogs must have an annual blood test first, since severe reactions can occur if preventive medications are inadvertently given to dogs with heartworms. (Your veterinarian is familiar with the extent of the heartworm problem in your area, and will advise you as to whether or not your dog should be tested and started on heartworm preventive.)  Infected dogs which are not treated can spread disease to other dogs.