Heartworm

  • CAPC “Parasite Prevalence Maps”

  • American Heartworm Society Maps

  • How To Mosquito-Proof Your Yard

  • Dr. Karen Shaw Becker Recommendations

  • Dr. Judy Morgan Recommendations

  • Dr. W. Jean Dodds Recommendations

  • Dr. Melissa Shelton Recommendations

CDC confirms oil of lemon eucalyptus as effective as DEET

Living in Southern California I have not given my dogs heartworm preventatives since I consider it low risk for my dogs. If I were choosing a heartworm preventative I would select Interceptor and its use would be dependent on the area and risk. “Timing of first monthly dose of heartworm preventative”

The Companion Animal Parasite Council (CAPC) provides “Parasite Prevalence Maps” tracking Heartworm, Intestinal Parasites, Tick Born Disease Agents, and Viral Diseases that affect both dogs and cats. (See above)

Every three years, the American Heartworm Society (AHS) gathers data on heartworm testing to understand the impact heartworm is having nationwide, as well as in specific regions. Testing data from thousands of veterinary practices and shelters is used to create a detailed map showing the average number of heartworm-positive cases per clinic. American Heartworm Society (AHS) Tracking the impact of heartworm disease


Dr. Karen Shaw Becker Recommendations

“The American Heartworm Society, heartworm drug manufacturers and many conventional veterinarians recommend giving preventives 12 months a year, no matter where you live or your pet's individual risk of exposure.” [1]

“This isn't a wise or logical approach, in my opinion, since where you live is the most important consideration in assessing your pet's risk. I absolutely do not agree that every pet, everywhere, should be given a chemical insecticide once a month, year in and year out.” [1]

“According to the 2019 heartworm prevalence map published by the Companion Animal Parasite Council (CAPC), just 1 out of every 75 dogs in the U.S. — about 1.3% — tests positive for heartworm.” [1]

“In addition, in only 11 states are dogs considered at high risk for heartworm infection. These numbers have remained essentially unchanged since the first map was created in 2012. The 11 states are primarily in the southeast, where soaring temperatures and high humidity during the warmer months of the year provide an ideal environment for mosquitoes to thrive.” [1]

“The rest of the U.S. ranges from three to seven months of high exposure risk. The majority of states are at six months or less. If you're concerned your dog is at risk of a heartworm infection, in consultation with your integrative veterinarian, you can use the following maps to guide you in when to start and stop a heartworm preventive.[1]

“It’s also important in mosquito-endemic areas to have your pet tested for heartworms and other parasitic diseases at the beginning and again at the end of pest season” [1]

American Heartworm Society (AHS)

American Heartworm Society (AHS)

Dr. Judy Morgan Recommendations

“It has been shown that maturation of larvae, within three mosquito species, ceases at temperatures below 57°F (14°C).  Thus, heartworm transmission does decrease in winter months, although the risk of transmission never reaches zero. The length of the heartworm transmission season in the temperate latitudes is critically dependent on the accumulation of sufficient heat to incubate larvae to the infective stage in the mosquito. The peak months for heartworm transmission in the Northern Hemisphere are typically July and August.” [2]  

” The heartworm preventives currently marketed (ivermectin, milbemycin oxime, moxidectin, and selamectin) belong to the macrocyclic lactone class of drugs. These drugs affect microfilariae, third- and fourth-stage larvae, and with continuous use, may affect adult heartworms.  Macrocyclic lactones, when given according to label instructions, are highly effective and are among the safest medications used in veterinary medicine.´[2]

“In my clinic the only preventative we carry is Interceptor, which contains milbemycin. Some clients opt for Sentinel, which also contains lufeneron, which prevents flea eggs from hatching. I do NOT recommend using Interceptor PLUS or Sentinel SPECTRUM, which also contain a tapeworm dewormer, praziquantel. Unless your pet has chronic flea infestation, they will not have chronic tapeworm infestation. Beware of products containing Moxidectin, a particularly dangerous chemical dewormer. Long-acting injections may seem convenient, but once given, there is no antidote to reverse side effects which may include the following adverse reactions: anaphylaxis, vomiting, diarrhea (with and without blood), listlessness, weight loss, seizures, and death.” [3]

“To be maximally effective, heartworm prophylaxis should be given year-round, but if seasonal treatment is chosen, administration should begin at least one month prior to the anticipated start of heartworm transmission and should continue for at least 3 months after transmission typically ceases. The latter 3-month recommendation emanates from new knowledge regarding resistant strains, which showed that extended treatment after exposure is required to prevent infection. Current data demonstrate that not all compounds and formulations necessitate this extension.” [2]

“Heartworm infection is preventable with this therapy.  Puppies should be started on preventives as early as possible, but no later than 8 weeks of age. Puppies started on a heartworm preventive after 8 weeks of age, or housed unprotected outdoors in heavily endemic areas, should be tested 6 months after the initial dose and annually thereafter. Before initiating a preventive regimen in older dogs (7 months of age or greater), heartworm antigen and microfilariae testing should be performed.” [2]

“Therapy to Kill Adult Heartworms:  The American Heartworm Society recommends use of doxycycline and a macrocyclic lactone prior to the three-dose regimen of melarsomine (arsenic; one injection of 2.5 mg/kg body weight followed at least one month later by two injections of the same dose 24 hours apart) for treatment of heartworm disease in both symptomatic and asymptomatic dogs. Any method utilizing only macrocyclic lactones (e.g. milbemycin oxime) as a slow-kill adulticide is not recommended.” [2]

Dr. W. Jean Dodds Recommendations

“Hemopet and Dr. Dodds advise the use of heartworm preventatives for healthy dogs – once the ambient temperature is above 57 degrees Fahrenheit (14 degrees Centigrade) for approximately two weeks and mosquitoes are prevalent. A basic rule of thumb is Mid-April through November for the majority of the country and basically year-round for the southern states.” [4]

Antimicrobial Resistance Series Part 3: Antiparasitic Resistance By W. Jean Dodds, DVM on July 28, 2019

“Puppies should be started on preventives as early as possible, but no later than 8 weeks of age. Puppies started on a heartworm preventive after 8 weeks of age, or housed unprotected outdoors in heavily endemic areas, should be tested 6 months after the initial dose and annually thereafter. Before initiating a preventive regimen in older dogs (7 months of age or greater), heartworm antigen and microfilariae testing should be performed.” [5]

“To be maximally effective, heartworm prophylaxis should be given year-round, but if seasonal treatment is chosen, administration should begin at least one month prior to the anticipated start of heartworm transmission and should continue for at least 3 months after transmission typically ceases. The latter 3-month recommendation emanates from new knowledge regarding resistant strains, which showed that extended treatment after exposure is required to prevent infection. Current data demonstrate that not all compounds and formulations necessitate this extension.” [5]

Canine Heartworm Disease W. Jean Dodds, DVM on January 14, 2016


Dr. Melissa Shelton Recommendations

“Essential oils should be part of every health program I feel - and completing small layers such as topical applications and diffusion are amazing tools in our tool box. If it is deemed necessary for your dog to have a preventive medication - especially if your dog has a compromised system in any way, shape, or form, or if heartworm is common in your area - then I do feel that a monthly preventive can be worth while in those situations. A dog on steroids, having "allergies", chronic stress, or disease - may be at further risk to get a heartworm infection that cannot be cleared by the body. So we may need some "traditional help" - and that is okay. But the type of traditional help is VERY important.”

“I suggest sticking with older, "tried and true" medications. Such as Heartgard and Interceptor (even Sentinel). These medications have been around for a very long time (even plain Ivermectin would be fine) - and have a much larger safety profile. While still not 100% benign, I certainly feel much better about the chronic use of these items, than with "new fangled" medications that are coming out on the market, designed to kill everything that could possibly affect your dog. I do not think we need to deworm for tapeworms every month etc... So if you ask me what to use - it will not include Revolution, Trifexis, Advantage Multi, and most certainly not injections such as ProHeart 6 etc... The same premise for flea and tick preparations...never use the "new" item for at least 1-2 years after it comes on the market, and if older items are available with a great track record, let's use those.”

“For my clients, even if a heartworm preventive is selected, I would like to see the dog using essential oils to help support the immune system, as well as to support the body from medications we give.”

“Why do I care about heartworm? Well first I am a veterinarian...but second my own dog was heartworm positive.” “I have no doubt that Babe's heartworm was greatly helped along through elimination by the holistic support we gave her. She was never administered a dewormer or heartworm pill while on her study - however eliminated both intestinal parasites and heartworm from her body over the course of 2 1/2 years, with confirmation of fully negative results 4 1/2 years later. Her health continued to improve along our journey, and today she is 100% happy, healthy, and active. In the veterinary community, I do not know of many vets who would expect a dog to be negative for heartworm in 4 years, without traditional treatments. Most would have only considered the fact that things would continue to get worse and worse, until Babe succumbed to massive numbers of adult heartworm.”

Heartworm Disease & Prevention Dr. Melissa Shelton




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