Ascariasis

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Ascariasis
Ascaris infection in X-ray image- Duedenal worms - in the first portion of the bowel after the stomach (South Africa) (16238958958).jpg
High number of ascaris worms – visible as black tangled mass – are filling the duodenum, the first portion of the bowel after the stomach, of this South African patient (X-ray image with barium as contrast medium).
Specialty Infectious disease
Symptoms Abdominal swelling, abdominal pain, diarrhea, shortness of breath [1]
CausesIngestion of Ascaris eggs [2]
PreventionImproved sanitation, handwashing [1]
Medication Albendazole, mebendazole, levamisole, pyrantel pamoate [2]
Frequency762 million (2015) [3]
Deaths2,700 (2015) [4]

Ascariasis is a disease caused by the parasitic roundworm Ascaris lumbricoides . [1] Infections have no symptoms in more than 85% of cases, especially if the number of worms is small. [1] Symptoms increase with the number of worms present and may include shortness of breath and fever in the beginning of the disease. [1] These may be followed by symptoms of abdominal swelling, abdominal pain, and diarrhea. [1] Children are most commonly affected, and in this age group the infection may also cause poor weight gain, malnutrition, and learning problems. [1] [2] [5]

Contents

Infection occurs by ingestion of food or drink contaminated with Ascaris eggs from feces. [2] The eggs hatch in the intestines, the larvae burrow through the gut wall, and migrate to the lungs via the blood. [2] There they break into the alveoli and pass up the trachea, where they are coughed up and may be swallowed. [2] The larvae then pass through the stomach for a second time into the intestine, where they become adult worms. [2] It is a type of soil-transmitted helminthiasis and part of a group of diseases called helminthiases. [6]

Prevention is by improved sanitation, which includes improving access to toilets and proper disposal of feces. [1] [7] Handwashing with soap appears protective. [8] In areas where more than 20% of the population is affected, treating everyone at regular intervals is recommended. [1] Reoccurring infections are common. [2] [9] There is no vaccine. [2] Treatments recommended by the World Health Organization are the medications albendazole, mebendazole, levamisole, or pyrantel pamoate. [2] Other effective agents include tribendimidine and nitazoxanide. [2]

About 0.8 to 1.2 billion people globally have ascariasis, with the most heavily affected populations being in sub-Saharan Africa, Latin America, and Asia. [1] [10] [11] This makes ascariasis the most common form of soil-transmitted helminthiasis. [10] As of 2010 it caused about 2,700 deaths a year, down from 3,400 in 1990. [12] Another type of Ascaris infects pigs. [1] Ascariasis is classified as a neglected tropical disease. [6]

Signs and symptoms

In populations where worm infections are widespread, it is common to find that most people are infected by a small number of worms, while a small number of people are heavily infected. This is characteristic of many types of worm infections. [1] [13] Those people who are infected with only a small number of worms usually have no symptoms. [14]

Migrating larvae

As larval stages travel through the body, they may cause visceral damage, peritonitis and inflammation, enlargement of the liver or spleen, and an inflammation of the lungs. Pulmonary manifestations take place during larval migration and may present as Loeffler's syndrome, a transient respiratory illness associated with blood eosinophilia and pulmonary infiltrates with radiographic shadowing. [15]

Intestinal blockage

Piece of intestine, blocked by worms, surgically removed from a three-year-old boy in South Africa Piece of intestine, blocked by worms (16424898321).jpg
Piece of intestine, blocked by worms, surgically removed from a three-year-old boy in South Africa

The worms can occasionally cause intestinal blockage when large numbers get tangled into a bolus or they may migrate from the small intestine, which may require surgery. [17] More than 796 A. lumbricoides worms weighing up to 550 g (19 oz) were recovered at autopsy from a two-year-old South African girl. The worms had caused torsion and gangrene of the ileum, which was interpreted as the cause of death. [18]

The worms lack teeth. However, they can rarely cause bowel perforations by inducing volvulus and closed-loop obstruction.[ citation needed ]

Bowel obstruction

Bowel obstruction may occur in up to 0.2 per 1000 per year. [1] A worm may block the ampulla of Vater, or go into the main pancreatic duct, resulting in acute pancreatitis with raised serum levels of amylase and lipase. Occasionally, a worm can travel through the biliary tree and even into the gallbladder, causing acute cholangitis or acute cholecystitis. [19] [ citation needed ]

Allergies

Ascariasis may result in allergies to shrimp and dustmites due to the shared antigen, tropomyosin; this has not been confirmed in the laboratory. [20] [21]

Malnutrition

The worms in the intestine may cause malabsorption and anorexia, which contribute to malnutrition. [22] The malabsorption may be due to a loss of brush border enzymes, erosion and flattening of the villi, and inflammation of the lamina propria. [23]

Others

Ascaris have an aversion to some general anesthetics and may exit the body, sometimes through the mouth, when an infected individual is put under general anesthesia. [24]

Cause

Ascaris life cycle: Adult worms (1) live in the lumen of the small intestine. A female may produce approximately 200,000 eggs per day, which are passed with feces (2). Unfertilized eggs may be ingested but are not infective. Fertile eggs embryonate and become infective after 18 days to several weeks (3), depending on the environmental conditions (optimum: moist, warm, shaded soil). After infective eggs are swallowed (4), the larvae hatch (5), invade the intestinal mucosa, and are carried via the portal, then systemic circulation and/or lymphatics to the lungs. The larvae mature further in the lungs (6) (10 to 14 days), penetrate the alveolar walls, ascend the bronchial tree to the throat, and are swallowed (7). Upon reaching the small intestine, they develop into adult worms (8). Between 2 and 3 months are required from ingestion of the infective eggs to oviposition by the adult female. Adult worms can live 1 to 2 years. Ascariasis LifeCycle - CDC Division of Parasitic Diseases.png
Ascaris life cycle: Adult worms (1) live in the lumen of the small intestine. A female may produce approximately 200,000 eggs per day, which are passed with feces (2). Unfertilized eggs may be ingested but are not infective. Fertile eggs embryonate and become infective after 18 days to several weeks (3), depending on the environmental conditions (optimum: moist, warm, shaded soil). After infective eggs are swallowed (4), the larvae hatch (5), invade the intestinal mucosa, and are carried via the portal, then systemic circulation and/or lymphatics to the lungs. The larvae mature further in the lungs (6) (10 to 14 days), penetrate the alveolar walls, ascend the bronchial tree to the throat, and are swallowed (7). Upon reaching the small intestine, they develop into adult worms (8). Between 2 and 3 months are required from ingestion of the infective eggs to oviposition by the adult female. Adult worms can live 1 to 2 years.

Transmission

The source of infection is from objects which have been contaminated with fecal matter containing eggs. [2] Ingestion of infective eggs from soil contaminated with human feces or contaminated vegetables and water is the primary route of infection. Infectious eggs may occur on other objects such as hands, money and furniture. [2] Transmission from human to human by direct contact is impossible. [25]

Transmission comes through municipal recycling of wastewater into crop fields. This is quite common in emerging industrial economies and poses serious risks for local crop sales and exports of contaminated vegetables. A 1986 outbreak of ascariasis in Italy was traced to irresponsible wastewater recycling used to grow Balkan vegetable exports. [26]

The number of ova (eggs) in sewage or in crops that were irrigated with raw or partially treated sewage, is a measure of the degree of ascariasis incidence.[ citation needed ] For example:

Lifecycle

The first appearance of eggs in stools is 60–70 days. In larval ascariasis, symptoms occur 4–16 days after infection. The final symptoms are gastrointestinal discomfort, colic and vomiting, fever, and observation of live worms in stools. Some patients may have pulmonary symptoms or neurological disorders during migration of the larvae. There are generally few or no symptoms. A bolus of worms may obstruct the intestine; migrating larvae may cause pneumonitis and eosinophilia. Adult worms have a lifespan of 1–2 years which means that individuals may be infected all their lives as worms die and new worms are acquired. [13]

Eggs can survive potentially for 15 years and a single worm may produce 200,000 eggs a day. [2] They maintain their position by swimming against the intestinal flow. [30]

Mechanism

Ascaris takes most of its nutrients from the partially digested host food in the intestine. There is some evidence that it can secrete enzyme inhibitors, presumably to protect itself from digestion by the hosts' enzymes. Children are often more severely affected. [1]

Diagnosis

Most diagnoses are made by identifying the appearance of the worm or eggs in feces. Due to the large quantity of eggs laid, diagnosis can generally be made using only one or two fecal smears. [31] The diagnosis is usually incidental when the host passes a worm in the stool or vomit. The eggs can be seen in a smear of fresh feces examined on a glass slide under a microscope and there are various techniques to concentrate them first or increase their visibility, such as the ether sedimentation method or the Kato technique. The eggs have a characteristic shape: they are oval with a thick, mamillated shell (covered with rounded mounds or lumps), measuring 35–50 micrometer in diameter and 40–70 in length. During pulmonary disease, larvae may be found in fluids aspirated from the lungs. White blood cell counts may demonstrate peripheral eosinophilia; this is common in many parasitic infections and is not specific to ascariasis. On X-ray, 15–35 cm long filling defects, sometimes with whirled appearance (bolus of worms).[ citation needed ]

Prevention

Prevention is by improved access to sanitation which includes the use of properly functioning and clean toilets by all community members as one important aspect. [1] Handwashing with soap may be protective; however, there is no evidence it affects the severity of the disease. [8] Eliminating the use of untreated human faeces as fertilizer is also important.[ citation needed ]

In areas where more than 20% of the population is affected treating everyone is recommended. [1] This has a cost of about 2 to 3 cents per person per treatment. [1] This is known as mass drug administration and is often carried out among school-age children. [32] For this purpose, broad-spectrum benzimidazoles such as mebendazole and albendazole are the drugs of choice recommended by WHO. [33]

Treatment

Medications

Medications that are used to kill roundworms are called ascaricides. Those recommended by the World Health Organization for ascariasis are: albendazole, mebendazole, levamisole and pyrantel pamoate. [2] Single‐dose of albendazole, mebendazole, and ivermectin are effective against ascariasis. They are effective at removing parasites and eggs from the intestines. [34] Other effective agents include tribendimidine and nitazoxanide. [2] Pyrantel pamoate may induce intestinal obstruction in a heavy worm load. Albendazole is contraindicated during pregnancy and children under two years of age. Thiabendazole may cause migration of the worm into the esophagus, so it is usually combined with piperazine.[ citation needed ]

Piperazine is a flaccid paralyzing agent that blocks the response of Ascaris muscle to acetylcholine, which immobilizes the worm. It prevents migration when treatment is accomplished with weak drugs such as thiabendazole. If used by itself, it causes the worm to be passed out in the feces and may be used when worms have caused blockage of the intestine or the biliary duct.[ citation needed ]

Corticosteroids can treat some of the symptoms, such as inflammation.[ citation needed ]

Other medications

  • Hexylresorcinol, effective in single dose. [35] During the 1940s this compound, as Crystoids brand pills, was the treatment of choice; patients were instructed not to chew the Crystoids in order to prevent burns to the mucous membranes. A saline cathartic would be administered several hours later. [36]
  • Santonin, more toxic than hexylresorcinol [35] and often only partly effective. [37]
  • Oil of chenopodium, more toxic than hexylresorcinol [35]

Surgery

In some cases with severe infestation the worms may cause bowel obstruction, requiring emergency surgery. [38] The bowel obstruction may be due to the number of worms in the bowel or twisting of the bowel. [38] During the surgery the worms may be manually removed. [38]

Prognosis

It is rare for infections to be life-threatening. [1]

Epidemiology

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Ascariasis deaths per million persons in 2012
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Disability-adjusted life year for ascariasis per 100,000 inhabitants in 2004
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Regions

Ascariasis is common in tropical regions as well as subtropical and regions that lack proper sanitation. It is rare to find traces of the infection in developed or urban regions. [39]

Infection estimates

Roughly 0.8–1.3 billion individuals are infected with this intestinal worm, primarily in Africa and Asia. [1] [2] [11] About 120 to 220 million of these cases are symptomatic. [1]

Deaths

As of 2010, ascariasis caused about 2,700 directly attributable deaths, down from 3,400 in 1990. [12] The indirectly attributable deaths due to the malnutrition link may be much higher.[ citation needed ]

Research

There are two animal models, the mouse and pig, used in studying Ascaris infection. [40] [41]

Other animals

Ascariasis is more common in young animals than mature ones, with signs including unthriftiness, potbelly, rough hair coat, and slow growth. [42]

In pigs, the infection is caused by Ascaris suum. It is characterized by poor weight gain, leading to financial losses for the farmer. [1]

In horses and other equines, the equine roundworm is Parascaris equorum.[ citation needed ]

Society and culture

Kings of England Richard III [43] and Henry VIII [44] both had ascariasis.

Related Research Articles

<i>Ascaris lumbricoides</i> One of several species of Ascaris

Ascaris lumbricoides is a large parasitic worm that causes ascariasis in humans. A roundworm of genus Ascaris, it is the most common parasitic worm in humans. An estimated 807 million–1.2 billion people are infected with A. lumbricoides worldwide. People living in tropical and subtropical countries are at greater risk of infection.

<i>Trichuris trichiura</i> Parasitic roundworm that causes intestinal infection

Trichuris trichiura, Trichocephalus trichiuris or whipworm, is a parasitic roundworm that causes trichuriasis when it infects a human large intestine. It is commonly known as the whipworm which refers to the shape of the worm; it looks like a whip with wider "handles" at the posterior end.

<span class="mw-page-title-main">Trichuriasis</span> Infection by Trichuris trichiura (whipworm)

Trichuriasis, also known as whipworm infection, is an infection by the parasitic worm Trichuris trichiura (whipworm). If infection is only with a few worms, there are often no symptoms. In those who are infected with many worms, there may be abdominal pain, fatigue and diarrhea. The diarrhea sometimes contains blood. Infections in children may cause poor intellectual and physical development. Low red blood cell levels may occur due to loss of blood.

<span class="mw-page-title-main">Helminthiasis</span> Any macroparasitic disease caused by helminths

Helminthiasis, also known as worm infection, is any macroparasitic disease of humans and other animals in which a part of the body is infected with parasitic worms, known as helminths. There are numerous species of these parasites, which are broadly classified into tapeworms, flukes, and roundworms. They often live in the gastrointestinal tract of their hosts, but they may also burrow into other organs, where they induce physiological damage.

Hymenolepiasis is infestation by one of two species of tapeworm: Hymenolepis nana or H. diminuta. Alternative names are dwarf tapeworm infection and rat tapeworm infection. The disease is a type of helminthiasis which is classified as a neglected tropical disease.

<span class="mw-page-title-main">Hookworm infection</span> Disease caused by intestinal parasites

Hookworm infection is an infection by a type of intestinal parasite known as a hookworm. Initially, itching and a rash may occur at the site of infection. Those only affected by a few worms may show no symptoms. Those infected by many worms may experience abdominal pain, diarrhea, weight loss, and tiredness. The mental and physical development of children may be affected. Anemia may result.

<i>Necator americanus</i> Species of hookworm

Necator americanus is a species of hookworm commonly known as the New World hookworm. Like other hookworms, it is a member of the phylum Nematoda. It is an obligatory parasitic nematode that lives in the small intestine of human hosts. Necatoriasis—a type of helminthiasis—is the term for the condition of being host to an infestation of a species of Necator. Since N. americanus and Ancylostoma duodenale are the two species of hookworms that most commonly infest humans, they are usually dealt with under the collective heading of "hookworm infection". They differ most obviously in geographical distribution, structure of mouthparts, and relative size.

<i>Ascaris suum</i> Species of roundworm

Ascaris suum, also known as the large roundworm of pig, is a parasitic nematode that causes ascariasis in pigs. While roundworms in pigs and humans are today considered as two species with different hosts, cross-infection between humans and pigs is possible; some researchers have thus argued they are the same species. Ascariasis is associated with contact to pigs and pig manure in Denmark.

<i>Ascaris</i> Genus of roundworms

Ascaris is a nematode genus of parasitic worms known as the "small intestinal roundworms", which is a type of parasitic worm. One species, Ascaris lumbricoides, affects humans and causes the disease ascariasis. Another species, Ascaris suum, typically infects pigs. Other ascarid genera infect other animals, such as Parascaris equorum, the equine roundworm, and Toxocara and Toxascaris, which infect dogs and cats.

<span class="mw-page-title-main">Parasitic worm</span> Large type of parasitic organism

Parasitic worms, also known as helminths, are large macroparasites; adults can generally be seen with the naked eye. Many are intestinal worms that are soil-transmitted and infect the gastrointestinal tract. Other parasitic worms such as schistosomes reside in blood vessels.

The soil-transmitted helminths are a group of intestinal parasites belonging to the phylum Nematoda that are transmitted primarily through contaminated soil. They are so called because they have a direct life cycle which requires no intermediate hosts or vectors, and the parasitic infection occurs through faecal contamination of soil, foodstuffs and water supplies. The adult forms are essentially parasites of humans, causing soil-transmitted helminthiasis (STH), but also infect domesticated mammals. The juveniles are the infective forms and they undergo tissue-migratory stages during which they invade vital organs such as lungs and liver. Thus the disease manifestations can be both local and systemic. The geohelminths together present an enormous infection burden on humanity, amounting to 135,000 deaths every year, and persistent infection of more than two billion people.

Necatoriasis is the condition of infection by Necator hookworms, such as Necator americanus. This hookworm infection is a type of helminthiasis (infection) which is a type of neglected tropical disease.

<i>Toxocara canis</i> Species of roundworm

Toxocara canis is a worldwide-distributed helminth parasite that primarily infects dogs and other canids, but can also infect other animals including humans. The name is derived from the Greek word "toxon," meaning bow or quiver, and the Latin word "caro," meaning flesh. T. canis live in the small intestine of the definitive host. This parasite is very common in puppies and somewhat less common in adult dogs. In adult dogs, infection is usually asymptomatic but may be characterized by diarrhea. By contrast, untreated infection with Toxocara canis can be fatal in puppies, causing diarrhea, vomiting, pneumonia, enlarged abdomen, flatulence, poor growth rate, and other complications.

<span class="mw-page-title-main">Pyrantel</span> Medication for parasitic worm infections

Pyrantel is a medication used to treat a number of parasitic worm infections. This includes ascariasis, hookworm infections, enterobiasis, trichostrongyliasis, and trichinellosis. It is taken by mouth.

<i>Toxascaris leonina</i> Species of roundworm

Toxascaris leonina is a common parasitic roundworm found in dogs, cats, foxes, and related host species. T. leonina is an ascarid nematode, a worldwide distributed helminth parasite which is in a division of eukaryotic parasites that, unlike external parasites such as lice and fleas, live inside their host. The definitive hosts of T. leonina include canids and felines (cats), while the intermediate hosts are usually rodents, such as mice or rats. Infection occurs in the definitive host when the animal eats an infected rodent. While T. leonina can occur in either dogs or cats, it is far more frequent in cats.

Ascaricides are drugs to treat ascariasis that is caused by infections with parasitic nematodes (roundworms) of the genus Ascaris. The large roundworm of pigs typically infects pigs while Ascaris lumbricoides affects human populations, typically in sub-tropical and tropical areas with poor sanitation. Ascaricides belong to the group of drugs collectively called anthelmintics which expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host.

<span class="mw-page-title-main">Pinworm infection</span> Medical condition

Pinworm infection, also known as enterobiasis, is a human parasitic disease caused by the pinworm, Enterobius vermicularis. The most common symptom is itching in the anal area. The period of time from swallowing eggs to the appearance of new eggs around the anus is 4 to 8 weeks. Some people who are infected do not have symptoms.

<span class="mw-page-title-main">Anthelmintic</span> Antiparasitic drugs that expel parasitic worms (helminths) from the body

Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host. They may also be called vermifuges or vermicides. Anthelmintics are used to treat people who are infected by helminths, a condition called helminthiasis. These drugs are also used to treat infected animals, particularly small ruminants such as goats and sheep.

<span class="mw-page-title-main">Soil-transmitted helminthiasis</span> Roundworm infection contracted from contaminated soil

Soil-transmitted helminthiasis is a type of worm infection (helminthiasis) caused by different species of roundworms. It is caused specifically by those worms which are transmitted through soil contaminated with faecal matter and are therefore called soil-transmitted helminths. Three types of soil-transmitted helminthiasis can be distinguished: ascariasis, hookworm infection and whipworm infection. These three types of infection are therefore caused by the large roundworm A. lumbricoides, the hookworms Necator americanus or Ancylostoma duodenale and by the whipworm Trichuris trichiura.

<span class="mw-page-title-main">Hookworm</span> Intestinal, blood-feeding, parasitic roundworms that cause types of infection known as helminthiases

Hookworms are intestinal, blood-feeding, parasitic roundworms that cause types of infection known as helminthiases. Hookworm infection is found in many parts of the world, and is common in areas with poor access to adequate water, sanitation, and hygiene. In humans, infections are caused by two main species of roundworm, belonging to the genera Ancylostoma and Necator. In other animals the main parasites are species of Ancylostoma. Hookworm is closely associated with poverty because it is most often found in impoverished areas, and its symptoms promote poverty through the educational and health effects it has on children. It is the leading cause of anemia and undernutrition in developing countries, while being one of the most commonly occurring diseases among poor people. Hookworm thrives in areas where rainfall is sufficient and keeps the soil from drying out, and where temperatures are higher, making rural, coastal areas prime conditions for the parasite to breed.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Dold C, Holland CV (July 2011). "Ascaris and ascariasis". Microbes and Infection. 13 (7): 632–7. doi:10.1016/j.micinf.2010.09.012. hdl: 2262/53278 . PMID   20934531.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Hagel I, Giusti T (October 2010). "Ascaris lumbricoides: an overview of therapeutic targets". Infectious Disorders Drug Targets. 10 (5): 349–67. doi:10.2174/187152610793180876. PMID   20701574.
  3. ↑ Vos T, Allen C, Arora M, Barber RM, Bhutta ZA, Brown A, et al. (GBD 2015 Disease and Injury Incidence and Prevalence Collaborators) (October 2016). "Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015". Lancet. 388 (10053): 1545–1602. doi:10.1016/S0140-6736(16)31678-6. PMC   5055577 . PMID   27733282.
  4. ↑ Wang H, Naghavi M, Allen C, Barber RM, Bhutta ZA, Carter A, et al. (GBD 2015 Mortality and Causes of Death Collaborators) (October 2016). "Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980-2015: a systematic analysis for the Global Burden of Disease Study 2015". Lancet. 388 (10053): 1459–1544. doi:10.1016/s0140-6736(16)31012-1. PMC   5388903 . PMID   27733281.
  5. ↑ "Soil-transmitted helminth infections Fact sheet N°366". World Health Organization. June 2013. Archived from the original on 2014-02-21.
  6. 1 2 "Neglected Tropical Diseases". cdc.gov. June 6, 2011. Archived from the original on 4 December 2014. Retrieved 28 November 2014.
  7. ↑ Ziegelbauer K, Speich B, Mäusezahl D, Bos R, Keiser J, Utzinger J (January 2012). "Effect of sanitation on soil-transmitted helminth infection: systematic review and meta-analysis". PLOS Medicine. 9 (1): e1001162. doi: 10.1371/journal.pmed.1001162 . PMC   3265535 . PMID   22291577.
  8. 1 2 Fung IC, Cairncross S (March 2009). "Ascariasis and handwashing". Transactions of the Royal Society of Tropical Medicine and Hygiene. 103 (3): 215–22. doi:10.1016/j.trstmh.2008.08.003. PMID   18789465.
  9. ↑ Jia TW, Melville S, Utzinger J, King CH, Zhou XN (2012). "Soil-transmitted helminth reinfection after drug treatment: a systematic review and meta-analysis". PLOS Neglected Tropical Diseases. 6 (5): e1621. doi: 10.1371/journal.pntd.0001621 . PMC   3348161 . PMID   22590656.
  10. 1 2 Keiser J, Utzinger J (2010). "The drugs we have and the drugs we need against major helminth infections". Advances in Parasitology. 73: 197–230. doi:10.1016/s0065-308x(10)73008-6. ISBN   978-0-12-381514-9. PMID   20627144.
  11. 1 2 Fenwick A (March 2012). "The global burden of neglected tropical diseases". Public Health. 126 (3): 233–236. doi:10.1016/j.puhe.2011.11.015. PMID   22325616.
  12. 1 2 Lozano R, Naghavi M, Foreman K, Lim S, Shibuya K, Aboyans V, et al. (December 2012). "Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010". Lancet. 380 (9859): 2095–128. doi:10.1016/S0140-6736(12)61728-0. hdl: 10536/DRO/DU:30050819 . PMID   23245604. S2CID   1541253.
  13. 1 2 Anderson RS, May RM (1991). Infectious diseases of humans. Dynamics and control. Oxford: Oxford Scientific Publications.
  14. ↑ "Parasites - Ascariasis". C.D.C, U.S. Department of Health & Human Services. 20 October 2020. Retrieved 27 June 2021.
  15. ↑ Torok E. Oxford Handbook Infect Dis and Microbiol, 2009
  16. ↑ Fincham, J., Dhansay, A. (2006). Worms in SA's children – MRC Policy Brief Archived 2015-04-02 at the Wayback Machine . Nutritional Intervention Research Unit of the South African Medical Research Council, South Africa
  17. ↑ Yetim, I; Ozkan, OV; Semerci, E; Abanoz, R (17 June 2009). "Rare cause of intestinal obstruction, Ascaris lumbricoides infestation: two case reports". Cases Journal. 2: 7970. doi:10.4076/1757-1626-2-7970. PMC   2740073 . PMID   19830032. S2CID   15081841.
  18. ↑ Baird JK, Mistrey M, Pimsler M, Connor DH (March 1986). "Fatal human ascariasis following secondary massive infection". The American Journal of Tropical Medicine and Hygiene. 35 (2): 314–8. doi:10.4269/ajtmh.1986.35.314. PMID   3953945.
  19. ↑ "Acute Cholangitis". The Lecturio Medical Concept Library. Retrieved 27 June 2021.
  20. ↑ Berman JJ (2012), Taxonomic Guide to Infectious Diseases: Understanding the Biologic Classes of Pathogenic Organisms, Academic Press, p. 151, ISBN   978-0-12-415895-5, archived from the original on 2013-05-30
  21. ↑ Reddy A, Fried B (2008). Rollinson D, Hay SI (eds.). "Atopic disorders and parasitic infections". Advances in Parasitology. 66: 149–91. doi:10.1016/S0065-308X(08)00203-0. ISBN   978-0-08-087900-0. PMID   18486690.
  22. ↑ Hall A, Hewitt G, Tuffrey V, de Silva N (April 2008). "A review and meta-analysis of the impact of intestinal worms on child growth and nutrition" (PDF). Maternal & Child Nutrition. 4 (Suppl 1): 118–236. doi:10.1111/j.1740-8709.2007.00127.x. PMC   6860651 . PMID   18289159.
  23. ↑ Stephenson LS (1987). The Impact of Helminth Infections on Human Nutrition. London: Taylor & Francis.
  24. ↑ Wu ML, Jones VA (January 2000). "Ascaris lumbricoides". Archives of Pathology & Laboratory Medicine. 124 (1): 174–5. doi:10.5858/2000-124-0174-AL. PMID   10629158.
  25. ↑ "AscarisInfection Fact Sheet". 2019-04-24. Archived from the original on 2010-05-31.
  26. ↑ Pawlowski ZS, Schultzberg K (1986). "Ascariasis and sewage in Europe". In Block JC (ed.). Epidemiological Studies of Risks Associated With the Agricultural Use of Sewage Sludge: Knowledge and Needs (EUR). Elsevier Science Pub Co. pp. 83–93. ISBN   978-1-85166-035-3.
  27. ↑ Bolbol AS (1992). "Risk of contamination of human and agricultural environment with parasites through reuse of treated municipal wastewater in Riyadh, Saudi Arabia". Journal of Hygiene, Epidemiology, Microbiology, and Immunology. 36 (4): 330–7. PMID   1300348.
  28. ↑ Horák P (1992). "Helminth eggs in the sludge from three sewage treatment plants in Czechoslovakia". Folia Parasitologica. 39 (2): 153–7. PMID   1644362.
  29. ↑ Habbari K, Tifnouti A, Bitton G, Mandil A (September 1999). "Helminthic infections associated with the use of raw wastewater for agricultural purposes in Beni Mellal, Morocco". Eastern Mediterranean Health Journal. 5 (5): 912–21. doi: 10.26719/1999.5.5.912 . PMID   10983530.
  30. ↑ Crompton DW, Pawlowski ZS (1985). "Life history and development of Ascaris lumbricoides and the persistence of human ascariasis.". In Crompton DW, Nesheim MC, Pawlowski ZS (eds.). Ascariasis and its public health significance. London: Taylor & Francis.
  31. ↑ Grove DI (1990). A history of human helminthology. Wallingford: CAB International. pp. 1–848. ISBN   0-85198-689-7.
  32. ↑ Mascarini-Serra L (April 2011). "Prevention of Soil-transmitted Helminth Infection". Journal of Global Infectious Diseases. 3 (2): 175–82. doi: 10.4103/0974-777X.81696 . PMC   3125032 . PMID   21731306.
  33. ↑ WHO (2006). Preventive Chemotherapy in Human Helminthiasis : Coordinated Use of Anthelminthic Drugs in Control Interventions : a Manual for Health Professionals and Programme Managers (PDF). WHO Press, World Health Organization, Geneva, Switzerland. pp. 1–61. ISBN   978-9241547109. Archived (PDF) from the original on 2013-02-28.
  34. ↑ Conterno LO, Turchi MD, Corrêa I, Monteiro de Barros Almeida RA, et al. (Cochrane Infectious Diseases Group) (April 2020). "Anthelmintic drugs for treating ascariasis". The Cochrane Database of Systematic Reviews. 2020 (4): CD010599. doi:10.1002/14651858.CD010599.pub2. PMC   7156140 . PMID   32289194.
  35. 1 2 3 Holt, Jr Emmett L, McIntosh Rustin: Holt's Diseases of Infancy and Childhood: A Textbook for the Use of Students and Practitioners. Appleton and Co, New York, 11th edition
  36. ↑ Most H (July 9, 1947). Clinical Aspects and Treatment of the More Common Intestinal Parasites of Man. Veterans Administration Technical Bulletins 1946 & 1947 Series 10. Washington, DC: U.S. Veterans Administration (published January 1948). pp. 8–9.
  37. ↑ Ravina E (2011). The evolution of drug discovery : from traditional medicines to modern drugs (1st ed.). Weinheim: Wiley-VCH. p. 91. ISBN   978-3-527-32669-3. Archived from the original on 2017-09-08.
  38. 1 2 3 Hefny AF, Saadeldin YA, Abu-Zidan FM (May 2009). "Management algorithm for intestinal obstruction due to ascariasis: a case report and review of the literature". Ulusal Travma ve Acil Cerrahi Dergisi = Turkish Journal of Trauma & Emergency Surgery. 15 (3): 301–5. PMID   19562557.
  39. ↑ "Parasites - Ascariasis". CDC, U.S. Department of Health & Human Services. 19 July 2019. Retrieved 27 June 2021.
  40. ↑ Howes HL (June 1971). "Anthelmintic studies with pyrantel. II. Prophylactic activity in a mouse-ascaris suum test model". The Journal of Parasitology. 57 (3): 487–93. doi:10.2307/3277899. JSTOR   3277899. PMID   5090955.
  41. ↑ Lichtensteiger CA, DiPietro JA, Paul AJ, Neumann EJ, Thompson L (April 1999). "Persistent activity of doramectin and ivermectin against Ascaris suum in experimentally infected pigs". Veterinary Parasitology. 82 (3): 235–41. doi:10.1016/S0304-4017(99)00018-7. PMID   10348103.
  42. ↑ "Parasites:Ascarids". eXtension. September 27, 2011. Archived from the original on 9 November 2014. Retrieved 9 November 2014.
  43. ↑ Mitchell PD, Yeh HY, Appleby J, Buckley R (September 2013). "The intestinal parasites of King Richard III". Lancet. 382 (9895): 888. doi:10.1016/S0140-6736(13)61757-2. hdl: 2381/31491 . PMID   24011545. S2CID   42898331.
  44. ↑ "Infected and Hunched: King Richard III Was Crawling with Roundworms". Live Science . 3 September 2013. Archived from the original on 2017-01-09. Retrieved 2017-01-07.
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