Highlights & Basics
- Ascariasis is concentrated in developing countries of Asia, Africa, and Latin America.
- Acquired by ingesting eggs that are passed in human feces and mature in the soil.
- Diagnosis can be made in most cases by finding characteristic eggs in a stool sample.
- Treated with oral anthelmintic agents.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Images
Photograph of 2 Ascaris lumbricoides nematodes; the larger one on the left is female and that on the right is male. Adult females can grow to >12 in (30 cm) in length
A fertilized egg of the roundworm Ascaris lumbricoides at magnification x 400. Fertilized eggs are rounded, with a thick shell. Unfertilized eggs are elongated, are larger, have thinner shells, and are covered by a more visible mammillated layer, which is sometimes covered by protuberances
Diagram depicting the various stages in the life cycle of the intestinal nematode Ascaris lumbricoides
Photomicrograph depicting a fertilized egg of the parasite Ascaris lumbricoides
Laboratory technician holding a mass of Ascaris lumbricoides worms excreted by a child in Kenya
Citations
World Health Organization. Soil-transmitted helminthiasis. Jan 2023 [internet publication].[Full Text]
Centers for Disease Control and Prevention. Parasites - ascariasis: resources for health professionals. May 2020 [internet publication].[Full Text]
World Health Organization. Preventive chemotherapy to control soil-transmitted helminth infections in at-risk population groups. September 2017 [internet publication].[Full Text]
1. Diemert DJ. Ascariasis. In: Guerrant RL, Walker DH, Weller PF, eds. Tropical infectious diseases: principles, pathogens and practice. 3rd ed. Edinburgh: W.B. Saunders; 2011:794-8.
2. Pullan RL, Smith JL, Jasrasaria R, et al. Global numbers of infection and disease burden of soil transmitted helminth infections in 2010. Parasit Vectors. 2014 Jan 21;7:37.[Abstract][Full Text]
3. Jourdan PM, Lamberton PHL, Fenwick A, et al. Soil-transmitted helminth infections. Lancet. 2018 Jan 20;391(10117):252-65.[Abstract]
4. Holland C, Sepidarkish M, Deslyper G, et al. Global prevalence of Ascaris infection in humans (2010-2021): a systematic review and meta-analysis. Infect Dis Poverty. 2022 Nov 18;11(1):113.[Abstract][Full Text]
5. Khuroo MS, Rather AA, Khuroo NS, et al. Hepatobiliary and pancreatic ascariasis. World J Gastroenterol. 2016;22:7507-7517.[Abstract][Full Text]
6. Lapid O, Krieger Y, Bernstein T, et al. Airway obstruction by Ascaris, roundworm in a burned child. Burns. 1999;25:673-675.[Abstract]
7. Hajizadeh M, Rahimi MT, Spotin A, et al. A rare cause of dysphagia: pharyngeal ascariasis. J Parasit Dis. 2016;40:1411-1413.[Abstract]
8. Chauhan A, Rastoqi P, Trikha S, et al. Esophageal ascariasis with retrosternal chest discomfort. J Assoc Physicians India. 2016;64:93.[Abstract]
9. Blumenthal DS, Schultz MG. Incidence of intestinal obstruction in children infected with Ascaris lumbricoides. Am J Trop Med Hyg. 1975;24:801-805.[Abstract]
10. de Silva NR, Chan MS, Bundy DA. Morbidity and mortality due to ascariasis: re-estimation and sensitivity analysis of global numbers at risk. Trop Med Int Health. 1997;2:519-28.[Abstract]
11. de Silva NR, Guyatt HL, Bundy DA. Morbidity and mortality due to Ascaris-induced intestinal obstruction. Trans R Soc Trop Med Hyg. 1997;91:31-36.[Abstract]
12. World Health Organization. Soil-transmitted helminthiasis. Jan 2023 [internet publication].[Full Text]
13. Cooper PJ. Interactions between helminth parasites and allergy. Curr Opin Allergy Clin Immunol. 2009;9:29-37.[Abstract][Full Text]
14. Krause RJ, Koski KG, Pons E, et al. Ascaris and hookworm transmission in preschool children in rural Panama: role of subsistence agricultural activities. Parasitology. 2016;22:1-12.[Abstract]
15. Lamberton PH, Jourdan PM. Human Ascariasis: Diagnostics Update. Curr Trop Med Rep. 2015;2(4):189-200.[Abstract][Full Text]
16. Schwartzman JD. Intestinal nematodes that migrate through lungs (Ascariasis). In: Strickland GT, ed. Hunter's tropical medicine. 7th ed. Philadelphia, PA: W.B. Saunders Company; 1991:696-700.
17. Galvani AP. Age-dependent epidemiological patterns and strain diversity in helminth parasites. J Parasitol. 2005;91:24-30.[Abstract]
18. Stephenson LS. The contribution of Ascaris lumbricoides to malnutrition in children. Parasitology. 1980;81:221-233.[Abstract]
19. Zhou C, Li M, Yuan K, et al. Pig Ascaris: an important source of human ascariasis in China. Infect Genet Evol. 2012 Aug;12(6):1172-7.[Abstract][Full Text]
20. Bieri FA, Gray DJ, Williams GM, et al. Health-education package to prevent worm infections in Chinese schoolchildren. N Engl J Med. 2013;368:1603-1612.[Abstract][Full Text]
21. Freeman MC, Clasen T, Brooker SJ, et al. The impact of a school-based hygiene, water quality and sanitation intervention on soil-transmitted helminth reinfection: a cluster-randomized trial. Am J Trop Med Hyg. 2013;89:875-883.[Abstract]
22. Hotez PJ. Parasitic nematode infections. In: Feigin RD, Cherry JD, Demmler-Harrison GJ, et al, eds. Textbook of pediatric infectious diseases. 6th ed. Philadelphia, PA: Saunders Elsevier; 2009:2981-2996.
23. Leung AKC, Leung AAM, Wong AHC, et al. Human ascariasis: an updated review. Recent Pat Inflamm Allergy Drug Discov. 2020;14(2):133-45.[Abstract][Full Text]
24. American Academy of Pediatrics; Committee on Infectious Diseases. In Kimberlin DW, Barnett ED, Lynfield R, et al, eds. Red Book: 2021-2024 Report of the Committee on Infectious Diseases. 32nd ed. Elk Grove Village, IL: American Academy of Pediatrics; 2021.[Full Text]
25. Cappello M, Hotez PJ. Intestinal nematodes. In: Long SS, Pickering LK, Prober CG. Principles and practice of pediatric infectious diseases. 2nd ed. New York, NY: Churchill Livingstone; 2003:1331-1339.
26. Gelpi AP, Mustafa A. Ascaris pneumonia. Am J Med. 1968:44:377-389.[Abstract]
27. Lübbert C, Schneitler S. Parasitic and infectious diseases of the biliary tract in migrants and international travelers. Expert Rev Gastroenterol Hepatol. 2016 Nov;10(11):1211-25.[Abstract][Full Text]
28. Crompton DW. Ascariasis and childhood malnutrition. Trans R Soc Trop Med Hyg. 1992;86:577-579.[Abstract]
29. Stephenson LS, Crompton DW, Latham MC, et al. Evaluation of a four year project to control Ascaris infection in children in two Kenyan villages. J Trop Pediatr. 1983;29:175-184.[Abstract]
30. Bethony J, Brooker S, Albonico M, et al. Soil-transmitted helminth infections: ascariasis, trichuriasis, and hookworm. Lancet. 2006;367:1521-1532.[Abstract]
31. Guyatt H. Do intestinal nematodes affect productivity in adulthood? Parasitol Today. 2000;16:153-8.[Abstract]
32. Garcia LS, Arrowood M, Kokoskin E, et al. Laboratory Diagnosis of Parasites from the Gastrointestinal Tract. Clin Microbiol Rev. 2018 Jan;31(1):e00025-17[Abstract][Full Text]
33. Coulibaly JT, Ouattara M, Becker SL, et al. Comparison of sensitivity and faecal egg counts of Mini-FLOTAC using fixed stool samples and Kato-Katz technique for the diagnosis of Schistosoma mansoni and soil-transmitted helminths. Acta Trop. 2016 Dec;164:107-16.[Abstract][Full Text]
34. Nikolay B, Brooker SJ, Pullan RL. Sensitivity of diagnostic tests for human soil-transmitted helminth infections: a meta-analysis in the absence of a true gold standard. Int J Parasitol. 2014 Oct 1;44(11):765-74.[Abstract][Full Text]
35. Crompton DW. Ascaris and ascariasis. Adv Parasitol. 2001;48:285-375.[Abstract]
36. Mahmood T, Mansoor N, Quraishy S, et al. Ultrasonographic appearance of Ascaris lumbricoides in the small bowel. J Ultrasound Med. 2001;20:269-274.[Abstract]
37. Ferreyra NP, Cerri GG. Ascariasis of the alimentary tract, liver, pancreas and biliary system: its diagnosis by ultrasonography. Hepatogastroenterology. 1998;45:932-937.[Abstract]
38. Beitia AO, Haller JO, Kantor A. CT findings in pediatric gastrointestinal ascariasis. Comput Med Imaging Graph. 1997;21:47-49.[Abstract]
39. Reeder MM. The radiological and ultrasound evaluation of ascariasis of the gastrointestinal, biliary, and respiratory tracts. Semin Roentgenol. 1998;33:57-78.[Abstract]
40. Baillie J. Endoscopic therapy in acute recurrent pancreatitis. World J Gastroenterol. 2008;14:1034-1037.[Abstract][Full Text]
41. Hall A, Romanova T. Ascaris lumbricoides: detecting its metabolites in the urine of infected people using gas-liquid chromatography. Exp Parasitol. 1990;70:35-42.[Abstract]
42. Petney TN, Andrews RH. Multiparasite communities in animals and humans: frequency, structure and pathogenic significance. Int J Parasitol. 1998 Mar;28(3):377-93.[Abstract][Full Text]
43. Seltzer E, Barry M, Crompton DWT. Ascariasis. In: Guerrant RL, Walker DH, Weller PF, eds. Tropical infectious diseases: principles, pathogens and practice. 2nd ed. Philadelphia, PA: Elsevier Churchill Livingstone; 2006:1257-1264.
44. Centers for Disease Control and Prevention. CDC Yellow Book 2024: health information for international travel. May 2023 [internet publication].[Full Text]
45. Centers for Disease Control and Prevention. Parasites - ascariasis: resources for health professionals. May 2020 [internet publication].[Full Text]
46. Conterno LO, Turchi MD, Corrêa I, et al. Anthelmintic drugs for treating ascariasis. Cochrane Database Syst Rev. 2020 Apr 14;4:CD010599.[Abstract][Full Text]
47. Moser W, Schindler C, Keiser J. Efficacy of recommended drugs against soil transmitted helminths: systematic review and network meta-analysis. BMJ. 2017 Sep 25;358:j4307.[Abstract][Full Text]
48. The Medical Letter, Inc. Drugs for parasitic infections. Med Lett Drugs Ther. 2007;5:e1-e15.
49. Biddulph J. Mebendazole and albendazole for infants. Pediatr Infect Dis J. 1990;9:373.[Abstract]
50. World Health Organization. Preventive chemotherapy to control soil-transmitted helminth infections in at-risk population groups. September 2017 [internet publication].[Full Text]
51. Khuroo MS. Ascariasis. Gastroenterol Clin North Am. 1996;25:553-577.[Abstract]
52. Spillmann RK. Pulmonary ascariasis in tropical communities. Am J Trop Med Hyg. 1975 Sep;24(5):791-800.[Abstract]
53. Gangopadhyay AN, Upadhyaya VD, Gupta DK, et al. Conservative treatment for round worm intestinal obstruction. Indian J Pediatr. 2007;74:1085-1087.[Abstract]
54. Vásquez Tsuji O, Gutiérrez Castrellón P, Yamazaki Nakashimada MA, et al. Anthelmintics as a risk factor in intestinal obstruction by Ascaris lumbricoides in children [in Spanish]. Bol Chil Parasitol. 2000;55:3-7.[Abstract]
55. Salman AB. Management of intestinal obstruction caused by ascariasis. J Pediatr Surg. 1997;32:585-587.[Abstract]
56. Hefny AF, Saadeldin YA, Abu-Zidan FM. Management algorithm for intestinal obstruction due to ascariasis: a case report and review of the literature. Ulus Travma Acil Cerrahi Derg (Turkish J Trauma Emerg Surg). 2009;15:301-305.[Abstract][Full Text]
57. Moser W, Coulibaly JT, Ali SM, et al. Efficacy and safety of tribendimidine, tribendimidine plus ivermectin, tribendimidine plus oxantel pamoate, and albendazole plus oxantel pamoate against hookworm and concomitant soil-transmitted helminth infections in Tanzania and Côte d'Ivoire: a randomised, controlled, single-blinded, non-inferiority trial. Lancet Infect Dis. 2017 Nov;17(11):1162-1171.[Abstract]
58. Willett WC, Kilama WL, Kihamia CM. Ascaris and growth rates: a randomized trial of treatment. Am J Public Health. 1979;69:987-991.[Abstract]
59. Awasthi A, Peto R, Pande V, et al. Effects of deworming on malnourished preschool children in India; an open-labelled, cluster-randomized trial. PLoS Negl Trop Dis. 2008;2:e223.[Abstract][Full Text]
60. Ochoa B. Surgical complications of ascariasis. World J Surg. 1991;15:222-227.[Abstract]
61. Stephenson LS, Crompton DW, Latham MC, et al. Relationships between Ascaris infection and growth of malnourished preschool children in Kenya. Am J Clin Nutr. 1980;33:1165-1172.[Abstract]
62. World Health Organization. Schistosomiasis and soil-transmitted helminthiases: number of people treated in 2016. Wkly Epidemiol Rec. 2017;92:749-60.[Full Text]
63. World Health Organization. Ending the neglect to attain the sustainable development goals: a road map for neglected tropical diseases 2021-2030. May 2020 [internet publication].[Full Text]
64. Taylor-Robinson DC, Maayan N, Donegan S, et al. Public health deworming programmes for soil-transmitted helminths in children living in endemic areas. Cochrane Database Syst Rev. 2019 Sep 11;9:CD000371.[Abstract][Full Text]
65. Salam RA, Das JK, Bhutta ZA. Effect of mass deworming with antihelminthics for soil-transmitted helminths during pregnancy. Cochrane Database Syst Rev. 2021 May 17;5(5):CD005547.[Abstract][Full Text]
66. Awasthi S, Peto R, Read S, et al. Population deworming every 6 months with albendazole in 1 million pre-school children in north India: DEVTA, a cluster-randomised trial. Lancet. 2013;381:1478-1486.[Abstract][Full Text]
67. Jia TW, Melville S, Utzinger J, et al. Soil-transmitted helminth reinfection after drug treatment: a systematic review and meta-analysis. PLoS Negl Trop Dis. 2012;6:e1621.[Abstract][Full Text]
68. Yap P, Du ZW, Wu FW, et al. Rapid re-infection with soil-transmitted helminths after triple-dose albendazole treatment of school-aged children in Yunnan, People's Republic of China. Am J Trop Med Hyg. 2013;89:23-31.[Abstract]
69. Strunz EC, Addiss DG, Stocks ME, et al. Water, sanitation, hygiene, and soil-transmitted helminth infection: a systematic review and meta-analysis. PLoS Med. 2014;11:e1001620.[Abstract][Full Text]
