Hookworm may be diagnosed if there is a personal history, such as residence in or travel to an endemic area, walking barefoot in contaminated soil, and symptoms of hookworm infection as described above. Individuals who walk barefoot or with open footwear are at particular risk of hookworm infection. Ideal soil conditions for the survival of larvae.Contamination of soil with human faeces.Three conditions are necessary for the spread of hookworm: The hookworms eventually reproduce, and the female worms lay eggs in the bowel. Hookworm infection in a pregnant woman leads to low birthweight babies, and infested children may fail to grow normally. Chronic blood loss leads to anaemia and tiredness. The hookworms feed off the host's blood and grow larger. At this stage, the infected individual may experience gastrointestinal symptoms such as nausea, diarrhoea, vomiting, and abdominal pain. Once the larvae have been swallowed, they travel to the small intestine where they mature into adult worms and attach to the intestinal wall. Infected individuals are often unaware of the larvae travelling through the lungs, but they may have a mild cough and throat discomfort. In a minority of patients, this phase is associated with generalised urticaria. Uncommonly, the larvae may migrate within the skin, producing a snake-like track similar to cutaneous larva migrans, which is due to infection by the hookworms that infect cats and dogs.Īs the hookworm larvae travel via the bloodstream to the lungs, they penetrate the lung air sacs and ascend the windpipe to the pharynx (the back of the mouth) and are swallowed. This may appear as a localised area of redness and swelling, or papules. Skin penetration by hookworm larvae produces a focal, itchy area at the site of infection (also called ‘ground itch’). There are four phases of hookworm infection: What are the symptoms of hookworm infestation? americanus tends to be found in North and South America, Central Africa, South Pacific islands, Indonesia, and certain parts of India. duodenale can be found in Mediterranean countries, the Far East, Iran, India, and Pakistan. Hookworm infections are most common in the tropics and subtropics.Ī. Two species commonly infest humans: Ancylostoma duodenale and Necator americanus. Hookworms are nematodes, parasites that live in the small intestine of the host.