Search tips
Search criteria 


Logo of cmrPermissionsJournals.ASM.orgJournalCMR ArticleJournal InfoAuthorsReviewers
Clin Microbiol Rev. 1992 January; 5(1): 93–100.
PMCID: PMC358225



Giardiasis is one of the most common pathogenic intestinal protozoal infections worldwide. Giardia lamblia is the most frequently identified etiologic agent in outbreaks associated with the ingestion of surface water, often due to ineffective filtration or pretreatment. In addition to humans, other sources of infection include beavers, perhaps muskrats, and possibly domestic animals. A low infecting dose (10 to 25 cysts) is reported to be sufficient to produce human infection. Clinical manifestations range from asymptomatic to a transient or persistent acute stage, with steatorrhea, intermittent diarrhea, and weight loss, or to a subacute or chronic stage that can mimic gallbladder or peptic ulcer disease. Diagnosis is usually based on repeated stool examinations but examination of duodenal fluid or biopsy material may also be necessary. Enzyme immunoassay or indirect immunofluorescence methods for direct detection of antigen or whole organisms in clinical specimens have also been developed. These tests are reported to be more sensitive than routine stool examination. Demonstration of serum immunoglobulin M and G antibodies may help differentiate recent from past infection or help detect recurrence in individuals who have been treated previously. Serum immunoglobulin A levels may be a useful indicator of exposure in waterborne outbreaks of diarrhea. Drugs available for treatment within the United States include metronidazole, quinacrine hydrochloride, and furazolidone.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.6M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Aggarwal A, Nash TE. Comparison of two antigenically distinct Giardia lamblia isolates in gerbils. Am J Trop Med Hyg. 1987 Mar;36(2):325–332. [PubMed]
  • Ament ME, Rubin CE. Relation of giardiasis to abnormal intestinal structure and function in gastrointestinal immunodeficiency syndromes. Gastroenterology. 1972 Feb;62(2):216–226. [PubMed]
  • Barbour AG, Nichols CR, Fukushima T. An outbreak of giardiasis in a group of campers. Am J Trop Med Hyg. 1976 May;25(3):384–389. [PubMed]
  • Beal CB, Viens P, Grant RG, Hughes JM. A new technique for sampling duodenal contents: demonstration of upper small-bowel pathogens. Am J Trop Med Hyg. 1970 Mar;19(2):349–352. [PubMed]
  • Bertram MA, Meyer EA, Lile JD, Morse SA. A comparison of isozymes of five axenic Giardia isolates. J Parasitol. 1983 Oct;69(5):793–801. [PubMed]
  • Birkhead G, Janoff EN, Vogt RL, Smith PD. Elevated levels of immunoglobulin A to Giardia lamblia during a waterborne outbreak of gastroenteritis. J Clin Microbiol. 1989 Aug;27(8):1707–1710. [PMC free article] [PubMed]
  • Blenkinsopp WK, Gibson JA, Haffenden GP. Giardiasis and severe jejunal abnormality. Lancet. 1978 May 6;1(8071):994–994. [PubMed]
  • Brandborg LL, Tankersley CB, Gottieb S, Barancik M, Sartor VE. Histological demonstration of mucosal invasion by Giardia lamblia in man. Gastroenterology. 1967 Feb;52(2):143–150. [PubMed]
  • Brodsky RE, Spencer HC, Jr, Schultz MG. Giardiasis in American travelers to the Soviet Union. J Infect Dis. 1974 Sep;130(3):319–323. [PubMed]
  • Burke JA. Giardiasis in childhood. Am J Dis Child. 1975 Nov;129(11):1304–1310. [PubMed]
  • Burke JA. The clinical and laboratory diagnosis of giardiasis. CRC Crit Rev Clin Lab Sci. 1977 Jun;7(4):373–391. [PubMed]
  • Chute CG, Smith RP, Baron JA. Risk factors for endemic giardiasis. Am J Public Health. 1987 May;77(5):585–587. [PubMed]
  • Cordingley FT, Crawford GP. Giardia infection causes vitamin B12 deficiency. Aust N Z J Med. 1986 Feb;16(1):78–79. [PubMed]
  • Craft JC. Giardia and giardiasis in childhood. Pediatr Infect Dis. 1982 May-Jun;1(3):196–211. [PubMed]
  • Craft JC, Nelson JD. Diagnosis of giardiasis by counterimmunoelectrophoresis of feces. J Infect Dis. 1982 Apr;145(4):499–504. [PubMed]
  • Craun GF. Waterborne giardiasis in the United States 1965-84. Lancet. 1986 Aug 30;2(8505):513–514. [PubMed]
  • Danciger M, Lopez M. Numbers of Giardia in the feces of infected children. Am J Trop Med Hyg. 1975 Mar;24(2):237–242. [PubMed]
  • Erlandsen SL, Sherlock LA, Bemrick WJ. The detection of Giardia muris and Giardia lamblia cysts by immunofluorescence in animal tissues and fecal samples subjected to cycles of freezing and thawing. J Parasitol. 1990 Apr;76(2):267–271. [PubMed]
  • Farthing MJ, Goka AJ. Immunology of giardiasis. Baillieres Clin Gastroenterol. 1987 Jul;1(3):589–603. [PubMed]
  • Giannella RA, Broitman SA, Zamcheck N. Influence of gastric acidity on bacterial and parasitic enteric infections. A perspective. Ann Intern Med. 1973 Feb;78(2):271–276. [PubMed]
  • Gillon J. Giardiasis: review of epidemiology, pathogenetic mechanisms and host responses. Q J Med. 1984 Winter;53(209):29–39. [PubMed]
  • Gillon J. Clinical studies in adults presenting with giardiasis to a gastro-intestinal unit. Scott Med J. 1985 Apr;30(2):89–95. [PubMed]
  • Goka AK, Rolston DD, Mathan VI, Farthing MJ. Diagnosis of giardiasis by specific IgM antibody enzyme-linked immunosorbent assay. Lancet. 1986 Jul 26;2(8500):184–186. [PubMed]
  • Goldman P. Metronidazole: proven benefits and potential risks. Johns Hopkins Med J. 1980 Jul;147(1):1–9. [PubMed]
  • Green EL, Miles MA, Warhurst DC. Immunodiagnostic detection of Giardia antigen in faeces by a rapid visual enzyme-linked immunosorbent assay. Lancet. 1985 Sep 28;2(8457):691–693. [PubMed]
  • Isaac-Renton JL, Byrne SK, Prameya R. Isoelectric focusing of ten strains of Giardia duodenalis. J Parasitol. 1988 Dec;74(6):1054–1056. [PubMed]
  • Istre GR, Dunlop TS, Gaspard GB, Hopkins RS. Waterborne giardiasis at a mountain resort: evidence for acquired immunity. Am J Public Health. 1984 Jun;74(6):602–604. [PubMed]
  • Janoff EN, Craft JC, Pickering LK, Novotny T, Blaser MJ, Knisley CV, Reller LB. Diagnosis of Giardia lamblia infections by detection of parasite-specific antigens. J Clin Microbiol. 1989 Mar;27(3):431–435. [PMC free article] [PubMed]
  • Jarroll EL, Bingham AK, Meyer EA. Effect of chlorine on Giardia lamblia cyst viability. Appl Environ Microbiol. 1981 Feb;41(2):483–487. [PMC free article] [PubMed]
  • Jokipii L, Jokipii AM. Single-dose metronidazole and tinidazole as therapy for giardiasis: success rates, side effects, and drug absorption and elimination. J Infect Dis. 1979 Dec;140(6):984–988. [PubMed]
  • Jones EG, Brown WR. Serum and intestinal fluid immunoglobulins in patients with giardiasis. Am J Dig Dis. 1974 Sep;19(9):791–796. [PubMed]
  • Kamath KR, Murugasu R. A comparative study of four methods for detecting Giardia lamblia in children with diarrheal disease and malabsorption. Gastroenterology. 1974 Jan;66(1):16–21. [PubMed]
  • Knisley CV, Engelkirk PG, Pickering LK, West MS, Janoff EN. Rapid detection of giardia antigen in stool with the use of enzyme immunoassays. Am J Clin Pathol. 1989 Jun;91(6):704–708. [PubMed]
  • Knox DL, King J., Jr Retinal arteritis, iridocyclitis, and giardiasis. Ophthalmology. 1982 Dec;89(12):1303–1308. [PubMed]
  • Korman SH, Le Blancq SM, Spira DT, el On J, Reifen RM, Deckelbaum RJ. Giardia lamblia: identification of different strains from man. Z Parasitenkd. 1986;72(2):173–180. [PubMed]
  • Koszarska J, Gruszczyńska M, Pilarska K. Lamblioza jako przyczyna ostrego zapalenia trzustki. Wiad Lek. 1977 Jun 1;30(11):875–877. [PubMed]
  • Kreutner AK, Del Bene VE, Amstey MS. Giardiasis in pregnancy. Am J Obstet Gynecol. 1981 Aug 15;140(8):895–901. [PubMed]
  • Meloni BP, Lymbery AJ, Thompson RC. Isoenzyme electrophoresis of 30 isolates of Giardia from humans and felines. Am J Trop Med Hyg. 1988 Jan;38(1):65–73. [PubMed]
  • Meloni BP, Thompson RC. Comparative studies on the axenic in vitro cultivation of Giardia of human and canine origin: evidence for intraspecific variation. Trans R Soc Trop Med Hyg. 1987;81(4):637–640. [PubMed]
  • Meyer EA, Radulescu S. Giardia and giardiasis. Adv Parasitol. 1979;17:1–47. [PubMed]
  • Murphy TV, Nelson JD. Five v ten days' therapy with furazolidone for giardiasis. Am J Dis Child. 1983 Mar;137(3):267–270. [PubMed]
  • Naik SR, Raue NR, Vinayak VK. A comparative evaluation of examinations of three stool samples, jejunal aspirate and jejunal mucosal impression smears in the diagnosis of giardiasis. Ann Trop Med Parasitol. 1978 Oct;72(5):491–492. [PubMed]
  • Naik SR, Rau NR, Vinayak VK, Narayanan VA, Zunzurwade S, Sehgal SC, Talwar P. Presence of Candida albicans in normal and in Giardia lamblia infected human jejunum. Ann Trop Med Parasitol. 1978 Oct;72(5):493–494. [PubMed]
  • Nash TE, Herrington DA, Levine MM. Usefulness of an enzyme-linked immunosorbent assay for detection of Giardia antigen in feces. J Clin Microbiol. 1987 Jul;25(7):1169–1171. [PMC free article] [PubMed]
  • Nash TE, Herrington DA, Losonsky GA, Levine MM. Experimental human infections with Giardia lamblia. J Infect Dis. 1987 Dec;156(6):974–984. [PubMed]
  • Nash TE, McCutchan T, Keister D, Dame JB, Conrad JD, Gillin FD. Restriction-endonuclease analysis of DNA from 15 Giardia isolates obtained from humans and animals. J Infect Dis. 1985 Jul;152(1):64–73. [PubMed]
  • Owen RL, Nemanic PC, Stevens DP. Ultrastructural observations on giardiasis in a murine model. I. Intestinal distribution, attachment, and relationship to the immune system of Giardia muris. Gastroenterology. 1979 Apr;76(4):757–769. [PubMed]
  • Petersen LR, Cartter ML, Hadler JL. A food-borne outbreak of Giardia lamblia. J Infect Dis. 1988 Apr;157(4):846–848. [PubMed]
  • Pickering LK, Engelkirk PG. Giardia lamblia. Pediatr Clin North Am. 1988 Jun;35(3):565–577. [PubMed]
  • Pickering LK, Woodward WE, DuPont HL, Sullivan P. Occurrence of Giardia lamblia in children in day care centers. J Pediatr. 1984 Apr;104(4):522–526. [PubMed]
  • RENDTORFF RC, HOLT CJ. The experimental transmission of human intestinal protozoan parasites. IV. Attempts to transmit Endamoeba coli and Giardia lamblia cysts by water. Am J Hyg. 1954 Nov;60(3):327–338. [PubMed]
  • Roberts-Thomson IC, Stevens DP, Mahmoud AA, Warren KS. Acquired resistance to infection in an animal model of giardiasis. J Immunol. 1976 Nov;117(5 PT2):2036–2037. [PubMed]
  • Rosoff JD, Stibbs HH. Isolation and identification of a Giardia lamblia-specific stool antigen (GSA 65) useful in coprodiagnosis of giardiasis. J Clin Microbiol. 1986 May;23(5):905–910. [PMC free article] [PubMed]
  • Rosoff JD, Stibbs HH. Physical and chemical characterization of a Giardia lamblia-specific antigen useful in the coprodiagnosis of giardiasis. J Clin Microbiol. 1986 Dec;24(6):1079–1083. [PMC free article] [PubMed]
  • Saha TK, Ghosh TK. Invasion of small intestinal mucosa by Giardia lamblia in man. Gastroenterology. 1977 Mar;72(3):402–405. [PubMed]
  • Schmerin MJ, Jones TC, Klein H. Giardiasis: association with homosexuality. Ann Intern Med. 1978 Jun;88(6):801–803. [PubMed]
  • Sealy DP, Schuman SH. Giardiasis: a common and underrecognized enteric pathogen. J Fam Pract. 1981 Jan;12(1):47–54. [PubMed]
  • Shaw RA, Stevens MB. The reactive arthritis of giardiasis. A case report. JAMA. 1987 Nov 20;258(19):2734–2735. [PubMed]
  • Smith JW, Wolfe MS. Giardiasis. Annu Rev Med. 1980;31:373–383. [PubMed]
  • Smith PD, Gillin FD, Brown WR, Nash TE. IgG antibody to Giardia lamblia detected by enzyme-linked immunosorbent assay. Gastroenterology. 1981 Jun;80(6):1476–1480. [PubMed]
  • Soto JM, Dreiling DA. Giardia lamblia. A case presentation of chronic cholecystitis and duodenitis. Am J Gastroenterol. 1977 Mar;67(3):265–269. [PubMed]
  • Stevens DP. Giardiasis: host-pathogen biology. Rev Infect Dis. 1982 Jul-Aug;4(4):851–858. [PubMed]
  • Stevens DP, Frank DM, Mahmoud AA. Thymus dependency of host resistance to Giardia muris infection: studies in nude mice. J Immunol. 1978 Feb;120(2):680–682. [PubMed]
  • Stibbs HH, Samadpour M, Manning JF. Enzyme immunoassay for detection of Giardia lamblia cyst antigens in formalin-fixed and unfixed human stool. J Clin Microbiol. 1988 Sep;26(9):1665–1669. [PMC free article] [PubMed]
  • Tandon BN, Tandon RK, Satpathy BK, Shriniwas Mechanism of malabsorption in giardiasis: a study of bacterial flora and bile salt deconjugation in upper jejunum. Gut. 1977 Mar;18(3):176–181. [PMC free article] [PubMed]
  • Thornton SA, West AH, DuPont HL, Pickering LK. Comparison of methods for identification of Giardia lamblia. Am J Clin Pathol. 1983 Dec;80(6):858–860. [PubMed]
  • Ungar BL, Yolken RH, Nash TE, Quinn TC. Enzyme-linked immunosorbent assay for the detection of Giardia lamblia in fecal specimens. J Infect Dis. 1984 Jan;149(1):90–97. [PubMed]
  • Vinayak VK, Kum K, Chandna R, Venkateswarlu K, Mehta S. Detection of Giardia lamblia antigen in the feces by counterimmunoelectrophoresis. Pediatr Infect Dis. 1985 Jul-Aug;4(4):383–386. [PubMed]
  • Visvesvara GS, Smith PD, Healy GR, Brown WR. An immunofluorescence test to detect serum antibodies to Giardia lamblia. Ann Intern Med. 1980 Dec;93(6):802–805. [PubMed]
  • Walzer PD, Wolfe MS, Schultz MG. Giardiasis in travelers. J Infect Dis. 1971 Aug;124(2):235–237. [PubMed]
  • WEBSTER BH. Human infection with Giardia lamblia; an analysis of 32 cases. Am J Dig Dis. 1958 Jan;3(1):64–71. [PubMed]
  • Wolfe MS. Giardiasis. N Engl J Med. 1978 Feb 9;298(6):319–321. [PubMed]
  • Wolfe MS. Giardiasis. Pediatr Clin North Am. 1979 May;26(2):295–303. [PubMed]
  • Wright RA, Vernon TM. Epidemic giardiasis at a resort lodge. Rocky Mt Med J. 1976 Jul-Aug;73(4):208–211. [PubMed]

Articles from Clinical Microbiology Reviews are provided here courtesy of American Society for Microbiology (ASM)