Heartworm disease in dogs is caused by a parasite Dirofilaria immitis and is transmitted by mosquitos that carry the parasite. For information on the history of heartworm disease and the life cycle of the parasite, please visit the following page before reading the guidelines and recommendations below.
http://bouldermountainvet.com/2011/05/heartworm-disease-in-colorado/
The following are general guidelines for heartworm testing and prevention. Because each dog’s lifestyle is different, if there is any confusion about whether your dog should be tested and/or on preventative it’s always best to ask about your dog’s specific situation. I generally recommend that dogs be tested every two years if they have not traveled outside of Colorado and have been given heartworm preventative during the previous mosquito season.
Heartworm disease is a devastating disease that can be painful and difficult to treat but is easily prevented with a very safe and inexpensive chewable ‘treat’ that is given once monthly. Some people choose not to use the preventative because heartworm disease is less common in Colorado than it is in other areas of the country. Dogs that are not given the preventative should be tested every spring.
Your dog should be tested for heartworm disease if ANY of the following apply:
1) the dog was not tested for heartworm disease last year
2) the dog was not on heartworm prevention during last mosquito season (May-Oct)
3) the dog has traveled outside of Colorado in the past year without heartworm prevention on his trip. This especially applies to dogs that have traveled to the east coast, the southeast, Texas, and the west coast.
4) your dog was on heartworm prevention last year but he missed a dose
5) your dog is a puppy 7 months or older
6) your dog was adopted recently and you don’t know the history. This is especially important for dogs that came from outside Colorado.
Your dog does not need to be tested this year (he will be tested next year) and can start heartworm prevention without testing if ALL of the following apply:
1) the dog had a negative heartworm test last year
2) the dog was given heartworm preventative May-October last year without missing any doses
3) the dog has not traveled outside of Colorado in the past year.
OR
the dog is a puppy under 7 months old
If you find any of the above information confusing, rest assured you are not alone. You may have heard different recommendations or have been given different information in the past. Please feel free to contact me with any questions. My goal is to help you make an informed decision and to be sure all dogs are protected against this deadly disease.
