Hookworms (Ancylostoma spp., Uncinaria stenocephala)
Why they matter: Can cause intestinal blood loss, especially in puppies; some species can affect people via skin contact.
How dogs get them: Ingesting larvae/eggs from contaminated soil or feces; larvae can also penetrate skin.
Common signs: Diarrhea, dark/tarry stool, weakness, pale gums, poor growth (or no signs).
Diagnosis: Fecal testing.
Treatment & prevention: Deworming plus year-round broad-spectrum parasite control and feces removal from the yard.
Human risk: Zoonotic hookworms can cause cutaneous larva migrans (itchy, winding skin lesions).