Prevalence of hookworm infection is the highest in developing, tropical countries. As much as 740 million people contract this infection. Although a serious parasitic infection, it is easily treatable, and preventable too.
|Gross to know…
The Ancylostoma duodenale hookworm species possesses 2 pointed ventral teeth on each side which it uses to suck blood from its host. The Necator americanus, however, do not have teeth but rounded ventral cutting plates.
Human hookworm infection does not cause any prominent symptoms, and that is why about 70% of people suffer from the infection without knowing about it. Mostly, Ancylostoma duodenale and Necator americanus are the species of hookworms that cause the infection. Infection from Ancylostoma duodenale occurs solely through direct contact of the skin with soil contaminated with the parasitic larvae. Infection caused by Necator americanus, on the other hand, can occur through penetration and oral transmission as well.
They Live on Blood…
Hookworms are known as blood suckers as they ingest blood from the host’s intestinal walls and damage the mucosa. A N. americanus hookworm can feed on 0.03 mL of blood per day, and a A. duodenale, 0.02 mL. The ill effect which follows includes anemia, and loss of iron (and protein) in the gut. Hookworm infection is more severe in children as it might cause growth retardation.
Journey to the Small Intestine…
In developing nations of the tropics and sub tropics, given the unavailability of proper sanitary disposal system, most people defecate directly on grounds. When an infected person does that, the eggs are passed along with the feces. These eggs mature, hatch, and develop into infective larvae in 7-10 days. Upon contact, these larvae attach themselves to the skin, usually on the foot, and break the skin to penetrate it. Thereafter, using the bloodstream as the carrier, they migrate in the body until they enter the lungs. The larvae are then expelled from the lungs into the mouth through cough, and from there they finally make their way to their feeding ground – the small intestine. Here they latch on to the intestinal walls and start feeding on the blood. It takes a few weeks before the larvae mature into adults and start mating. Females can produce up to 30,000 eggs per day, which are excreted in the feces, and the cycle continues.
There are no specific signs of hookworm infection in humans, particularly at the start of the infection. However, people who suffer from long-term infection tend to be thin, tired, and weak. Anemia may be associated with the symptoms which occur due to heavy infestation. Probable symptoms which might occur in an event where a person has been affected by a large number of larvae include:
• Abdominal discomfort
• Increased gas production
• Bloody sputum
• Loss of appetite
• Nausea and vomiting
• Black stools
• Eggs and blood in the stool
• Itchy rash (at the penetrated area; also called “ground itch”)
Medicines such as mebendazole or albendazole are recommended for the treatment as they help in killing adult hookworms. Pyrantel pamoate is another medicine which can be used in both humans as well as dogs, however, the dosages vary. Studies have revealed that a moderately small number of hookworms does not raise any concern, provided there is enough iron in the diet. Problems occur when these parasites start growing rapidly in the body.
The best defense against hookworm infection comprises measures such as avoiding direct skin contact with soil in areas where the infection is common, not using night soil as a form of fertilizer, and regularly deworming pets. Hookworm infection is usually not fatal, but it may be severe for infants and people who are already undernourished.
Disclaimer: The information provided in this article is solely for educating the reader. It is not intended to be a substitute for the advice of a medical expert.