Symptoms of hookworm infection

Symptoms depend on how many worms are present, the animal's age, and its overall health. A lightly infected adult may show almost nothing; a heavily infected puppy can become critically ill within days. The thread running through all of it is blood loss.

Common signs

• Pale gums. The clearest at-home anemia check — healthy gums are bubble-gum pink, anemic gums look pale or whitish.
• Dark, tarry, or bloody stool. Digested blood turns stool black; fresh blood appears as streaks.
• Weight loss & poor condition. A dull, dry coat and visible ribs despite normal appetite.
• Weakness & lethargy. Tiring easily, reluctance to play, exercise intolerance.
• Diarrhea. Often soft or mucoid, sometimes with that dark tarry colour.
• Poor growth in the young. Puppies, kittens and young stock that fail to thrive or fall behind littermates.

Why young animals are hit hardest

A newborn has a small blood volume, so the same worm burden that an adult shrugs off can drain a puppy or kitten dangerously. Ancylostoma caninum larvae can also pass directly to nursing puppies through the mother's milk, meaning a litter can be infected before it ever touches the ground.

How it's confirmed

Symptoms point the way, but diagnosis is made in the lab. A veterinarian runs a fecal flotation to find hookworm eggs under the microscope, often alongside bloodwork to gauge the degree of anemia. Because eggs aren't shed continuously, a single negative test doesn't always rule infection out — your vet may repeat it.