Heartworms and Health Certificates
As I write this, it is Sunday and I'm on call, waiting for a sick dog to arrive. So I've been reading some FAX messages, from Charlie Powell, who is the Public Information Director of the Washington State Veterinary Medical Association. I had questions so I called Charlie's number, expecting to leave a message on his answering machine. But Charlie himself answered and gave me the information for this column.
One FAX said people traveling from Washington into Canada with their pet dogs do not need a health certificate. I asked Charlie what those folks would need to come back into the U.S. from Canada.
He said, "That's the rub and there's not a clear answer." The problem is, there are four entities that have authority at those border crossings - the U.S. Customs, U.S. Border Patrol, Canadian Customs, and Canadian Border Patrol. Each of these has it's own directives and policies, and the bottom line is, if any one of these four agents thinks you need a health certificate for your dog, you may either have to go somewhere and get one or spend a few days proving you don't need it.
Your veterinarian can write a health certificate. It is simple and not very expensive, and it may save you the extra cost of getting one on a Sunday at the border. And don't forget to bring a current rabies certificate - you are supposed to have that.
***
Charlie also told me about a recent article in the Spokane newspaper that is raising eyebrows amongst veterinarians. A veterinarian in the area reported that she had found positive heartworm tests on a dog and two cats that had never traveled outside the Spokane area. The slant of the article was that "the invasion has arrived" and you'd better put your dogs and cats on the monthly preventative medication.
Heartworms are a serious problem in areas where there are mosquitoes that live long enough to effectively spread the disease. A mosquito cannot transmit the disease by biting an infective dog, and then immediately biting another dog. After a mosquito bites an infected dog, any heartworm larvae that come with the dog's blood must go through a developmental stage inside the mosquito. It takes two to three weeks for the larvae to develop and migrate to the mouthparts of the mosquito, and until that happens, the mosquito cannot spread the disease. Even if the dog and the two cats did get bitten and infected by mosquitoes from the Spokane area, the chances of this being the start of an epidemic are pretty slim. It takes longer unbroken strings of warm days and nights than we've had, or are likely to have. In fact, it is probably more likely these pets were infected last summer, or even before that.
The article also suggested that adopted stray canine refugees from the Katrina hurricane might have been responsible for bringing heartworms to our neighborhood. They may have brought some heartworms, but for many years dogs with heartworms have turned up among the pets of military personnel, as well as other people, moving here from heartworm endemic areas. A few years ago someone brought several heavily infected hound dogs from the south into an area along the Washington/Canadian border. There were a few infections from those dogs, but that "epidemic" seems to have petered out.
The bottom line is, if heartworms ever become endemic here, it won't be because of imported heartworm positive dogs. Your dog doesn't need heartworm preventatives now, and probably won't - until global warming makes significant changes in our climate.