Veterinary medicine is a constantly evolving profession. A good vet must be willing to adapt the way he or she practices as new discoveries change the field.
Heartworms are blood parasites of dogs and cats. They are spread by mosquitoes, and they can cause heart failure. Veterinary parasitologists, who are the experts on the subject of heartworms, have been sounding alarm bells about the worms for several years. They worry that heartworm disease is a growing threat to pets. And some experts believe that many vets are not treating young animals with heartworm preventatives appropriately.
Most vets recommend starting heartworm preventatives at four to six months of age. But an online discussion forum that occurred through the Veterinary Information Network (VIN) on October 5 challenged this mantra.
Dr. Tom Nelson, moderator of the forum, pointed out that two months of age (or perhaps earlier) is a more appropriate time to begin heartworm prevention. His argument was based on features of the heartworm life cycle and the means by which preventatives protect pets.
I won’t bore you with all of the details. But I am going to change my recommendations for heartworm prevention in young animals.
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How do I know if my dog has parasites?
I have a five-year-old Jack
Russell. My dog goes to the vet twice a year and
has blood work done before I put her on
Revolution. Can the blood tests detect
parasites?
Jan
Whitby, Canada
Three classes of parasites are common in dogs and cats. Each class causes unique symptoms.
Skin parasites such as fleas and mites are very common. In some instances, fleas or flea feces may be present on infested pets. In many other cases the parasites are not detectable with the naked eye but may cause hair loss, scabs or red skin. Skin tests are used to detect skin parasites.
Blood parasites such as heartworm are common in many parts of the world. Blood parasites may cause heart problems, anemia, and immune system disorders. Blood tests are required to check for blood parasites.
Intestinal parasites comprise the third class of animal parasites. Intestinal worms and microscopic parasites such as Giardia and coccidia fall into this class. Intestinal parasites may cause diarrhea or vomiting, but many infested pets show no symptoms whatsoever. Microscopic evaluation of the stool is required to check for intestinal parasites.
No test for parasites is 100% accurate. Therefore, if you want to keep your pet free of parasites your best bet is to use a broad spectrum anti-parasite agent on a regular basis. Revolution is one such agent. If your dog receives Revolution each month, it is unlikely that she is infested with parasites. Advantage Multi is another effective broad spectrum anti-parasite agent. Interceptor and Heartgard Plus also prevent most parasite infestations when combined with a flea preventative such as Advantage, Frontline, Comfortis or Vectra 3D.
Some animal parasites can spread to people. Intestinal roundworms are the most dangerous. Broad spectrum anti-parasite medicines do not only help to keep your pet healthy. They also help protect the people in the house.
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Hi -
I am fostering a dog while a family relocates. I
just found out that their dog is not on heartworm
medication but mine are. What risk, if any, are
my dogs at from the unprotected dog?
Cindy
Michigan
None whatsoever.
Heartworms are blood parasites that are spread by mosquitoes. When an infected mosquito bites a cat or dog, microscopic larvae are injected into the bloodstream. Over several months, the larvae mature into worms that live in the heart and the arteries leading out of the heart.
Cats and dogs suffering from heartworm infestation may show symptoms of heart failure such as coughing, shortness of breath and decreased exercise tolerance. Vomiting is a common symptom in cats.
Fortunately, heartworms cannot spread directly from one pet to another. A mosquito must be involved in the process. What’s more, heartworm larvae must develop in the mosquito for 12 - 19 days before they can infest another pet. Therefore, even if a mosquito bites the foster dog and then bites one of your dogs, your dogs won’t be at increased risk.
Finally, you state that your dogs are on a heartworm preventative. If you use a high-quality preventative as directed, it should afford excellent protection against the parasite regardless of other circumstances. In other words, you don’t need to worry.
See related Vet Blog entries:
Veterinary medicine is a constantly evolving profession. A good vet must be willing to adapt the way he or she practices as new discoveries change the field.
You have questions. 