Overview
- Published February 10, 2026, the PeerJ paper reanalyzed roughly 6,500 citizen-science reports from 2013–2025 in metropolitan France.
- Researchers documented 15 instances of flatworms stuck to pet fur—13 on cats and 2 on dogs—with every case identified as Caenoplana variegata.
- Between 2020 and 2024, 7.3% of C. variegata reports (10 of 137) involved observations linked to dogs or cats.
- C. variegata’s sticky mucus and asexual reproduction in Europe make hitchhiking likely and establishment possible from a single individual.
- An estimated 18 billion km traveled annually by French pets makes rare carriage events plausible, prompting calls for targeted monitoring and pet-owner checks focused on ecological risk, not animal health.