The fox lungworm, Crenosoma vulpis, continues to be identified in dogs in Ontario. The attached map from WormsAndGermsMap shows the cases we know about. There aren’t many, but the issue of “rare vs rarely diagnosed” is important. As a relatively new (or newly identified) problem that requires specific testing, it’s easy for it to be overlooked. The distribution on the map shows how widely lungworm cases have been spread across the province.

Lungworm is a possible cause of chronic cough dogs in areas where the parasite is present. That now includes much of Ontario. Readily treatable, it’s important that lungworm testing is considered in cases of chronic respiratory disease, particularly those that have not been recently or routinely treated with antiparasitics that are effective against lungworms.