Lungworms are a type of parasite that can infect the respiratory tract. There are several different parasites that have been identified including: Paragonimus kellicotti, Capillaria aerophilia, Filaroides and Osleri spp.

Outdoor pets in certain geographic areas of North America and elsewhere are predisposed to respiratory parasites. Infection typically occurs from exposure to the hosts that carry the parasite.

The lung fluke (Paragonimus) is found near lakes that harbor the intermediate host (crayfish and snails) or the raccoons that eat them. Dogs that hunt and eat raccoon meat may be at risk.

The tracheal (windpipe) worm Osleri osleri is directly transmitted from the mother to pup.

Clinically important infections occur most often in younger animals, those less than two years old, that are heavily infested.

The symptoms for lungworm infections depend on the specific parasite, the severity of the infection and the host response. Some pets with mild infections are normal, while other pets will exhibit a cough, lethargy, exercise intolerance and weight loss.

What to Watch For

Coughing is the most common sign of lungworm infection.

Diagnosis

Veterinary care should include diagnostic tests and subsequent treatment recommendations. Diagnostic tests are needed to recognize lungworms, and exclude other diseases. Tests may include:

Complete medical history and physical examination including lung auscultation (stethoscope examination)

Thoracic radiographs (chest X-rays)

Fecal examination must be done to check for ova or larvae. A special technique called the Baermann technique may be required.

Examination of respiratory secretions should be done to check for ova or larvae. These secretions may be obtained by a procedure called transtracheal or endotracheal wash.

A heartworm test should be performed to exclude this disease.

Treatment

If lungworms are diagnosed, an anti-parasite drug must be given. Often these are the common "dewormers" used for roundworms, hookworms and tapeworms in dogs.

If there is severe reaction to the parasite, an anti-inflammatory dose of corticosteroids may be needed for a brief period, usually three to 10 days.

Home Care and Prevention

In addition to careful observation, you may be asked to medicate your pet for this condition. This can be a challenge in some cases and you should ask for help at your veterinarian's office if you need directions regarding proper medication techniques. A variety of medications may be prescribed depending on the exact parasite identified and are in the form of liquids or pills.

The only effective preventative is to control the roaming and hunting of dogs allowed out-of-doors. In the case of Osleri osleri infection, the bitch (mother) should also be treated for the tracheal worm.