Fleas pose health risks to pets, including allergic reactions and skin irritation. They can also infest homes, spreading to carpets, furniture, and floorboards, making eradication challenging. Flea collars, while commonly used, may contain chemicals that could be harmful to both pets and humans, as noted by Consumer Reports. Regular inspections of pets and homes are essential to catch infestations early and minimize risks. Fleas can thrive in warm, shady outdoor areas, increasing the likelihood of reinfestation if yards are not properly maintained.