Intestinal worms are also known as soil – transmitted helminthes (STH) and they are the most common NTDs worldwide. STHs are caused by a group or parasitic worms and the most common of them are whipworm (trichuriasis), roundworm (ascariasis) and hookworm. They are either transmitted by ingesting parasite eggs or trough contaminated soil. In the world there are 604 million people infected with trichuriasis, 807 million people infected with ascariasis and 700 million people which are infected with hookworm (in this number are also included pregnant women and their number is 44 million).  This transmission is usually happening in the tropical climates and where hygiene and sanitation are poor. Once, the hookworm was one of the biggest public health problems in the South of the United States of America.  This parasite was so widespread and the economy of the South was also affected. It is known fact that morbidity is directly related to worm burden and this means that the greater number of worms is in the infected person, the greater will be the severity of this disease in the affected person.
Symptoms of intestinal worms
We know that intestinal worms are parasites which are deriving their nutrition from the human gut. The mentioned types of worms can live in different parts of the intestines which is causing differing symptom patterns. People who have mild to moderate intestinal worm infestations may not show symptoms.
- Diarrhea: This is the most common symptom of intestinal roundworm and fluke infestation including fasciolopsiasis, trichinosis, strongyloidiasis, ancylostomiasis and trichuriasis. You should know that diarrhea is not a typical symptom of tapeworm infestations. 
- Abdominal pain: This is possible symptom of any of the tapeworm, fluke or roundworm infestations in our intestines (human intestines). We know that this symptom is least likely to happen with the largest intestinal worms and those are tapeworms. Abdominal pain which is associated with intestinal worms typically is intermittent and cramping. Sudden onset of severe abdominal pain may signal intestinal obstruction which can happen with heavy infestation of the roundworms – Ascaris lumbricoides. 
- Growth retardation: Children are having increased chances of having nutritional deficiencies which are caused by infestations of intestinal roundworms. There was one study in which was said that the severe cases of ascariasis, trichuriasis, strongyloidiasis and ancylostomiasis can cause growth retardation and malnutrition. Also when there are severe cases of strongyloidiasis and ancylostomiasis, then the weight loss can happen. 
- Fatigue: This can be a symptom of infestation with intestinal worms, especially those that feed off the blood supply flowing through our intestines. There was one study in which is said that the severe cases of strongyloidiasis and ancylostomiasis can provoke fatigue and anemia. Also the long – standing infection with the fish type tapeworm – Diphyllobothrium latum can lead to Vitamin B12 deficiency which can cause anemia. The fish tapeworm infestation can also cause fatigue.
- Cough and lung congestion: The life cycle of some types of roundworms is involving migration of an immature form of the worm through our lungs. The presence of this immature worm can trigger an inflammatory reaction which is known as pulmonary eosinophilia. There are some doctors who have said that symptoms can include wheezing, chest pain, fever, shortness of breath and dry cough. Roundworm infestations which are associated with pulmonary eosinophilia are including trichinosis, strongyloidiasis, ancylostomiasis and ascariasis. 
- Worms in the stool: There was one study in which is said that people with tapeworm infestations, including diphyllobothriasis and taeniasis, may pass large segments of the worms in the stool. We know that the tapeworms are the largest of the intestinal worms and the passed segments can be substantial. On the other hand there are pinworms which are thread – like worms and they are less than one half inch long. Also these worms can be passed in the stool but in many cases they can be unnoticed. 
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