In details

Hookworm: Yellowish

Hookworm is a helminthiasis that can be caused by either the Ancylostoma duodenale as at Necatur americanus.

Both are small, worm-like worms measuring between 1 and 1.5 cm. The disease may also be popularly known as "yellowing", "jeca-armadillo disease", "ailing", "miner anemia," opilation ", etc.

People with this worm are pale, with yellowish skin, because the worms live in the small intestine and, with their sharp plates or teeth, tear the intestinal walls, suck blood and cause bleeding and anemia.

The person becomes infected by maintaining contact with the soil contaminated by manure. Filarioid larvae actively penetrate through the skin (when ingested, can penetrate through the mucosa). The larvae originate in eggs eliminated by man.

Previous portion of Ancylostoma duodenaleshowing mouth with lacerating denticles.

Life cycle

Adult worms live in a man's small intestine. After mating, the eggs are expelled with the feces (the female of the Ancylostoma duodenale lays up to 30,000 eggs a day, while that of the Necator americanus put 9 thousand). Finding favorable conditions in the heat (heat and humidity), they become embryonic 24 hours after expulsion.

The larva thus originated is called rabitoid. It leaves the eggshell and becomes free-living in the soil. After a week, on average, it becomes a larva that can penetrate through a man's skin called a larva. filarioid weed

When individuals walk barefoot in these areas, the filarioid larvae penetrate the skin, migrate to the lymphatic capillaries of the dermis, and then move to the blood capillaries, being carried through the circulation to the heart and finally to the lungs.

Then they pierce the pulmonary capillaries and the alveolar wall, migrate through the bronchioles and reach the pharynx. They then descend down the esophagus and reach the small intestine, where they become adults.

Another contamination is by the encysted filarioid larva (the larval encystation may occur in the soil) which, if ingested orally, reaches the adult state in the small intestine, without following the pathways previously described.

Detailed life cycle

1- Larvae actively penetrate through the skin, reach the circulation and perform a journey similar to that made by roundworm larvae, migrating from the heart to the pulmonary alveoli.

2- From the alveoli, they go to the bronchi, trachea, larynx, pharynx, esophagus, stomach and small intestine, where they become adults.

3- After mating in the intestine, the females start laying eggs, which, when mixed with the feces, are eliminated to the soil. The difference with ascariasis is that in this case the eggs hatch into the soil and release a larva.

4- In damp, dark soil, the larvae stay alive and feed. Suffer changes in the cuticle during this period.


At the site of filarioid larvae penetration, an inflammatory (itchy) reaction occurs. In the course, cough or even pneumonia (passage of the larvae through the lungs) may be observed. Next, intestinal disturbances appear which are manifested by cramps, nausea and hemorrhages resulting from the plundering action of the teeth or sharp plaques in the mouth of these worms. These hemorrhages can last a long time, leading to intense anemia, which aggravates the condition.

Complications may occur, such as cachexia (deep malnutrition), amenorrhea (absence of menstruation), deliveries with a dead fetus and, in children, growth disorders.

The main preventive measures consist of the construction of adequate sanitary facilitiesthus preventing the worms' eggs from contaminating the soil; wearing shoes, preventing the penetration of the larvae by the feet. In addition to treating patients, a comprehensive health education campaign is needed. Otherwise, the man will always run the risk of getting the worm again.
In the treatment of the sick, the classic remedy is befene; Pirantel, mebendazole and thiabendazole are also effective.