Changes

===Clinical Signs===

===Clinical Signs===

Heartworm disease tends to develop slowly and gradually

The onste of disease due to ''Dirofilaria immitis'' is insidious, and clinical sign are related either to a high parasite burden, or to an allergic response to the parasite². Signs often only manifest during exercise, and so patients with a sedentary lifestyle may never show overt disease.

and clinical signs are usually only present in cases

 

with a high worm burden and/or when the host has a

In dogs,

significant allergic response to the parasite. Frequently,

clinical signs of D immitis infection only manifest during

intense exercise and, therefore, sedentary patients may

never show overt signs of heartworm disease. In dogs,

coughing is the most common clinical sign, followed by

coughing is the most common clinical sign, followed by

tachypnoea and dyspnoea, exercise intolerance, chronic

tachypnoea and dyspnoea, exercise intolerance, chronic