Heartworm Resistance Update September 2011
In “Time to Step It Up” (WDJ July 2011), we described one small study that showed only Advantage Multi was 100 percent effective against the MP3 strain of resistant heartworms after a single dose. The report was true as far as it went, but new points have emerged that make this a more complex story and one for which we do not have all the answers yet.
Study Reveals Most Common Diseases in Dogs
Banfield Pet Hospital has issued a report analyzing the most common diseases in dogs and cats. The “State of Pet Health 2011 Report” collected data from 2.1 million dogs seen at Banfield’s 770 veterinary hospitals in 2010. Some of the more interesting findings included increases in diabetes, dental disease, ear infections, and flea infestations since 2006. Hookworms and whipworms in dogs also increased during that time period.
Some Heartworm Preventative Medications Have Become Less Effective
As we reported in Whole Dog Journal in March 2011, there is now ample evidence that at least one strain of heartworms has developed resistance to some of the market's best-known preventives. In addition, there is evidence to suggest that one of the most popular heartworm preventives, Heartgard, has an efficacy rate of less than 100 percent. The U.S. Food and Drug Administration's Center for Veterinary Medicine has sent at least one warning letter to Merial, the maker of Heartgard, asking the company to stop claiming 100 percent effectiveness for heartworm prevention. Given these developments, what should responsible dog owners do differently to better protect their dogs? The answer depends a bit on where you live and what you've already been doing to prevent heartworm infection.
Allegations From a Former Merial Insider Regarding Heartgard’s Ineffectiveness
The lawsuit filed by Kari Blaho-Owens, PhD, against Merial, her former employer, contains a number of serious allegations regarding Heartgard’s decreased efficacy and Merial’s knowledge of the problem.We may never know whether all the details alleged in the suit are true. It might take years in court – or it might be settled out of court. But the suit makes for fascinating reading.
When Buying Veterinary Drugs Online, Look for Accredited Sites
Purchasing veterinary medications such as heartworm preventatives online can offer significant cost savings, but how can you be sure that you're buying the real thing and not counterfeit products from China, which can be impossible to tell apart? I recently read about a dog who tested positive for heartworms despite being given monthly preventative medications. The reason may be that the heartworm preventative the owner purchased online was not what it claimed to be.
ProMeris Discontinued
Pfizer has announced plans to discontinue manufacture and sale of its flea and tick control product, ProMeris. Orders will continue to be filled until September 20, 2011. ProMeris was introduced in the fall of 2007, and touted as the first topical product to use metaflumizone. Pfizer gained control of ProMeris when it acquired Wyeth/Fort Dodge Animal Health in 2009. Pfizer is also the maker of Revolution, used to control fleas and one species of ticks, along with heartworm, ear mites, and sarcoptic mange.
Corticosteroids: Lifesaver or Killer?
There are almost as many opinions among veterinarians concerning the use of corticosteroids as there are veterinarians. Some feel that these drugs – prednisone, prednisolone, methylprednisolone, and dexamethasone foremost among them – are invaluable to every dog who itches; some feel that corticosteroids ought to be used only as a last resort, and only for short periods and in small amounts. Still others regard them as verboten. Why are these drugs so controversial?
Are Heartworms Developing Resistance to Preventatives?
In August 2010, representatives of the American Heartworm Society (AHS), the Companion Animal Parasite Council (CAPC), and experts in the field of nematode resistance met in Atlanta. Their goal was to discuss the possibility of heartworms becoming resistant to macrocyclic lactones
Shortage of Immiticide for Canine Heartworm Treatment
On December 1, 2009, Merial published an open letter to veterinarians, announcing a shortage of Immiticide (melarsomine dihydrochloride), the only drug licensed for use in treating heartworm infestations in dogs. The shortage is due to a manufacturing site transfer. The company expressed hope that the shortage will not persist beyond the first quarter of this year.
Canine Pain Management
Pain may be the most enigmatic of all the disease symptoms of man or beast. It is a sensation we all have experienced at one time or another and in varying degrees. But, few of us can explain adequately how a particular pain feels, fewer still can give a reasonable explanation for why pain occurs; and despite all the recent scientific research that has gone into pain, we still have a minimal understanding for how it occurs – or truthfully, for how to consistently prevent or alleviate it.
Letters: 08/06
American BioSciences
Blauvelt