How Do Dogs Get Heartworm?

Heartworm is a disease that you would not want your pet to have. It is a serious disease that can affect your dog and is potentially fatal.

As the name suggests, heartworm is called such because it lives in the heart of the dog. Other than the heart, it also goes to the the lungs and associated blood vessels. Heartworms are foot long worms that causes heart failure and lung disease that leads to organ failure in the dog’s body.

Although there are other animals that are affected by heartworms, dogs are natural hosts for them. This means that heartworms can mature to adulthood inside the dog undetected.

How is heartworm transmitted to your dog?

The culprit of heartworm disease is no other than the lowly mosquito. When a mosquito bites an infected animal with heartworm, the blood taken is with baby worms called microflaria.

Stages of Heartworms

There are 5 larva stages of the heartworms (L1 to L5). The baby worms go through L1 to L3 while inside the mosquito.

L3 larva is ready to infect other animals. It is in L3 stage that these larvae go into a dog’s bloodstream when bitten by an infected mosquito.

In the dog’s bloodstream, the L3 larva develops into L4 in as early as 2 to 5 days after infection. From L4, it takes around 2 months to be an L5 larva.

At this stage, the larvae has entered adulthood. At about 90 days inside the bloodstream, they have reached the heart and stays there. From the heart, they grow rapidly in length and size. Heartworms can live from 5 to 7 years.

Heartworm Symptoms in Dogs

In the early stage of heartworm infection, dogs will show no sign of it. Even a blood test will not detect these heartworms initially.

Symptoms will only show when the L5 larvae has arrived in the heart and surrounding blood vessels.

Some of these signs include mild persistent cough, fatigue after some mild activity, loss of appetite and weight loss. Heartworms blocks the blood vessels and can threaten the life of your dog.

Treatment for heartworm disease can take a toll on your dog not to mention your finances. Especially when the heartworms have penetrated the heart, lungs and blood vessels of your pet.

The best way to avoid heartworm disease is getting the heartworm preventatives. It is recommended that your puppy start this at 8 weeks of age. At 7 months, their blood should be tested for heartworm. Then annual tests is recommended as per veterinarian’s advice.

Learn More About Heartworm at Makati Dog and Cat Hospital


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