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Filed in Dogs, Health

Q: Should I have my dog tested for heartworm? I used to live an area where heartworm was a real problem, but here people don't seen as concerned.

A: Heartworm is a deadly disease carried by mosquitoes, and in many parts of the country it has become a serious epidemic. Now the disease is gradually spreading wherever there are mosquitoes.

In many parts of the world, heartworm is the single biggest health problem for dogs.

Dog owners who want to be careful and protect their pets from this spreading, life-threatening disease should ask their veterinarians to test their pets for heartworm. If your dog's test is negative, your veterinarian will recommend a simple preventive program, usually consisting of one tablet of medication each month. This not only protects your pet, but also helps stop the spread of this disease.

It is very important never to give heartworm medication to dogs that have not been tested or that have tested positive for heartworm because it can make them very sick.

It is particularly critical for any dog that travels to areas where heartworm is a problem to be tested for heartworm and put on a preventive program.

The spread of heartworm begins when a mosquito bites an infected dog. The mosquito withdraws blood containing microscopic immature heartworm larvae called microfilaria. Inside the mosquito, the microfilaria undergoes a series of changes, and within two or three weeks develop into ineffective larvae. The larvae are then passed into another dog when the mosquito takes its next blood meal.

Continuing their development in the dog, the larvae mature into adult worms in about six months. Adult heartworms are six to ten inches long and collect primarily in the right chambers of the heart and in blood vessels that take blood to the lungs.

Microfilaria are continually released by female heartworms and circulate throughout the dog's body. The adult heartworms cause damage by increasing the work load of the heart and impairing circulation to the lungs, liver and kidneys.

When heartworm begins affecting the dog's heart, signs include coughing, lack of energy and reduced appetite.

If a blood test for heartworms is positive, the dog usually is given intravenous medication to kill the worms. The dog must be monitored very carefully during this time because it may become very sick as the heartworms die.

Symptoms of heartworm disease usually are not evident until after major organs have been damaged. This makes early detection and prevention very important.

Source: Ask the Vet, reprinted with permission by Pet Food Express. Ask the Vet is published by Veterinarian's Best, Inc.

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