There's something lurking in the waters left behind by the recent rains that can be deadly to dogs and cats -- and it's much smaller than an alligator.

The standing water left behind has quickly become a breeding ground for mosquitoes and as all pet owners know that can lead to heartworms in unprotected dogs and cats.

Heartworms are found in just about every area of the United States, including Alaska and although there are preventatives available animals still contract the disease. Many of the animals that go into humane shelters are heartworm-positive.

Animals contract heartworms through a bite from a mosquito with the infected larval form of the heartworm. The heartworm larva can grow and develop into worms that live inside blood vessels within and surrounding the animal's heart and lungs. A trip to the veterinarian is all that is needed to have a dog tested and to get a prescription for an appropriate dosage for his weight. Tests before prescribing the preventative are needed to ensure the animal is not already infected. Federal regulations require the medicine be prescribed by a veterinarian.