Updates on Emerging and Evolving Gastrointestinal Parasites in Dogs and Cats

Gastrointestinal parasites are a common veterinary concern and pet owner conversation. Globally, parasite ranges and abundances are evolving, and various clinical management challenges in dogs and cats have emerged. Some of these are novel, such as hookworm multi-drug resistance, and others have been veterinary challenges for years, like Giardia's zoonotic potential. For these examples and others, there has been increased awareness of the need for appropriate veterinary anthelmintic use and stewardship. This review provides an update on selected gastrointestinal parasites of One Health importance, highlights gastrointestinal parasite global management and prevention recommendations, and summarises recent research, along with potential risks associated with pet importation and travel. Suggestions on freely available online resources to assist with practical veterinary clinical management (screening, diagnosis, treatment, prevention) and pet owner communication, along with addressing One Health and antiparasitic stewardship concerns, are provided from a global perspective, for example The European Scientific Counsel for Companion Animal Parasites. Clinical cases are drawn from molecular diagnostic faecal surveillance of dogs and cats during 2022 and 2023, and include the following gastrointestinal parasites with zoonotic potential: hookworms (Ancylostoma caninum), tapeworms (Echinococcus multilocularis), roundworms (Baylisascaris procyonis) and Giardia.