We report 2 autochthonous feline thelaziosis cases caused by the eyeworm Thelazia callipaeda and discuss the spread among dogs in the northeastern United States. Phylogenetic analysis suggests the parasite was introduced from Europe. Adopting a One Health approach is needed to limit further spread of T. callipaeda eyeworms in North America.
Keywords: One Health; Thelazia callipaeda; United States; cats; dogs; eyeworm; parasites; thelaziosis; zoonoses.