5. Address the envelope. In the lower right third of the envelope, write the name of the person you are sending the letter to. Write the company name on the line below that (if there is a company name).
Once inside a new host, it takes approximately 6 months for the larvae to mature into adult heartworms. Once mature, heartworms can live for 5 to 7 years in dogs and up to 2 or 3 years in cats. Because of the longevity of these worms, each mosquito season can lead to an increasing number of worms in an infected pet.
This means that if you opt to treat a heartworm positive dog with an ivermectin-based heartworm. preventive only, you can expect the dog to remain heartworm positive for as long as two to three years. and the heartworm disease will be progressing during those two years. This is not good for the dog but.