How contaminated soil becomes infectious
Hookworms do not pass directly from fresh feces into a person. Their eggs leave an infected person’s body in stool; in warm, damp soil, the eggs hatch and the young worms develop into larvae capable of entering human skin. Open defecation or poorly managed sanitation can bring those larvae into places where people walk or work barefoot.
A journey that ends in the intestine
After entering the skin, larvae are carried in the blood toward the lungs. They cross into the airways, are moved upward by coughing and swallowing, and reach the small intestine. There they mature and attach to the intestinal lining, where they feed on blood. The adult worms can produce eggs that leave in stool, restarting the cycle if they reach suitable soil.
The route through the lungs is part of the parasite’s life cycle, not its final home. Skin entry may cause an itchy rash; later, infection can cause abdominal symptoms. Because the worms take blood, a substantial or prolonged infection can lead to iron-deficiency anemia, which may cause tiredness and weakness.
Why shoes and sanitation matter
Shoes form a barrier between skin and infectious larvae, while toilets and safe disposal of feces keep eggs from reaching the soil where they can develop. Breaking either link interrupts the cycle: fewer larvae can reach people, and fewer eggs return to the ground.
