History

After exposure in nonimmune individuals, the incubation period is usually1-14+ days (mean, 7 d). The onset of illness may be abrupt in as many as 30% of cases, with watery diarrhea containing mucus or blood.^[17]It may be preceded by a flulike illness.^[25]After a few days, acute symptoms subside and then may recur (61% of cases) in a waxing-waning pattern. Alternatively, a patient may experience persistent symptoms. The illness usually lasts 6-7 weeks but has been reported to persist for several months. The duration can be several months to a year in patients with HIV.

Watery diarrhea (may be explosive) with a median of 6 stools per day; frequency of diarrhea possibly many times higher; no diarrhea in some patients.
Anorexia
Weight loss (0.9-3.6 kg in one study)
Fatigue, often pronounced
Abdominal cramping
Belching
Abdominal bloating
Vomiting
Low-grade fever (25%)
Flatulence
Headache
Nausea

Physical

Vital signs are normal in most cases. Fever is unusual but, when present, is low grade. In the presence of moderate to severe dehydration, compensatory tachycardia, systolic blood pressure (SBP) less than 90 mm Hg, and decreased skin turgor may occur, and the patient may appear ill.

Causes

Risk for infection is secondary to the consumption of contaminated fruits, vegetables, water, or other foodstuffs (see Deterrence/Prevention for strategies that decrease the risk of acquiring this infection). The infectious inoculum is unknown, but is thought to be small (eg, ingestion of 10-100 oocysts).^[26]

Differential Diagnoses

Ortega YR, Sanchez R. Update on Cyclospora cayetanensis, a food-borne and waterborne parasite. Clin Microbiol Rev. 2010 Jan. 23 (1):218-34. [QxMD MEDLINE Link].
Sun T, Ilardi CF, Asnis D, Bresciani AR, Goldenberg S, Roberts B, et al. Light and electron microscopic identification of Cyclospora species in the small intestine. Evidence of the presence of asexual life cycle in human host. Am J Clin Pathol. 1996 Feb. 105 (2):216-20. [QxMD MEDLINE Link].
Barlaam A, Temesgen TT, Tysnes KR, Rinaldi L, Ferrari N, Sannella AR, et al. Contamination of fresh produce sold on the Italian market with Cyclospora cayetanensis and Echinococcus multilocularis. Food Microbiol. 2021 Sep. 98:103792. [QxMD MEDLINE Link].
Shlim DR, Cohen MT, Eaton M, Rajah R, Long EG, Ungar BL. An alga-like organism associated with an outbreak of prolonged diarrhea among foreigners in Nepal. Am J Trop Med Hyg. 1991 Sep. 45(3):383-9. [QxMD MEDLINE Link].
Ortega YR, Sterling CR, Gilman RH, Cama VA, Díaz F. Cyclospora species--a new protozoan pathogen of humans. N Engl J Med. 1993 May 6. 328(18):1308-12. [QxMD MEDLINE Link].
Centers for Disease Control and Prevention. Update: outbreaks of Cyclospora cayetanensis infection--United States and Canada, 1996. MMWR Morb Mortal Wkly Rep. 1996 Jul 19. 45(28):611-2. [QxMD MEDLINE Link]. [Full Text].
Pape JW, Verdier RI, Boncy M, Boncy J, Johnson WD Jr. Cyclospora infection in adults infected with HIV. Clinical manifestations, treatment, and prophylaxis. Ann Intern Med. 1994 Nov 1. 121(9):654-7. [QxMD MEDLINE Link].
Hall RL, Jones JL, Hurd S, Smith G, Mahon BE, Herwaldt BL. Population-based active surveillance for Cyclospora infection--United States, Foodborne Diseases Active Surveillance Network (FoodNet), 1997-2009. Clin Infect Dis. 2012 Jun. 54 Suppl 5:S411-7. [QxMD MEDLINE Link].
Global Health, Division of Parasitic Diseases and Malaria. Domestically Acquired Cases of Cyclosporiasis — United States, May–August 2019. Centers for Disease Control and Prevention. Available at https://www.cdc.gov/parasites/cyclosporiasis/outbreaks/2019/a-050119/index.html. 2021 July 04; Accessed: 2021 July 04.
CDC. Parasites - Cyclosporiasis (Cyclospora Infection). Centers for Disease Control and Prevention. Available at https://www.cdc.gov/parasites/cyclosporiasis/outbreaks/index.html. 2021 July 4; Accessed: 2021 July 4.
Almeria S, Shipley A. Detection of Cyclospora cayetanensis on bagged pre-cut salad mixes within their shelf-life and after sell by date by the U.S. food and drug administration validated method. Food Microbiol. 2021 Sep. 98:103802. [QxMD MEDLINE Link].
Hall NB, Chancey RJ, Keaton AA, Heines V, Cantu V, Vakil V, et al. Cyclosporiasis Epidemiologically Linked to Consumption of Green Onions: Houston Metropolitan Area, August 2017. J Food Prot. 2020 Jan 21. 326-330. [QxMD MEDLINE Link].
Baldursson S, Karanis P. Waterborne transmission of protozoan parasites: review of worldwide outbreaks - an update 2004-2010. Water Res. 2011 Dec 15. 45(20):6603-14. [QxMD MEDLINE Link].
Orozco-Mosqueda GE, Martínez-Loya OA, Ortega YR. Cyclospora cayetanensis in a Pediatric Hospital in Morelia, México. Am J Trop Med Hyg. 2014 Sep 3. 91(3):537-40. [QxMD MEDLINE Link]. [Full Text].
Thima K, Mori H, Praevanit R, Mongkhonmu S, Waikagul J, Watthanakulpanich D. Recovery of Cyclospora cayetanensis among asymptomatic rural Thai schoolchildren. Asian Pac J Trop Med. 2014 Feb. 7(2):119-23. [QxMD MEDLINE Link].
Liu H, Shen Y, Yin J, Yuan Z, Jiang Y, Xu Y, et al. Prevalence and genetic characterization of Cryptosporidium, Enterocytozoon, Giardia and Cyclospora in diarrheal outpatients in China. BMC Infect Dis. 2014 Jan 13. 14:25. [QxMD MEDLINE Link]. [Full Text].
Sánchez-Vega JT, Cabrera-Fuentes HA, Romero-Olmedo AJ, Ortiz-Frías JL, Sokolina F, Barreto G. Cyclospora cayetanensis: this emerging protozoan pathogen in Mexico. Am J Trop Med Hyg. 2014 Feb. 90(2):351-3. [QxMD MEDLINE Link]. [Full Text].
Insulander M, Svenungsson B, Lebbad M, Karlsson L, de Jong B. A foodborne outbreak of Cyclospora infection in Stockholm, Sweden. Foodborne Pathog Dis. 2010 Dec. 7 (12):1585-7. [QxMD MEDLINE Link].
Centers for Disease Control and Prevention (CDC). Notes from the field: use of electronic messaging and the news media to increase case finding during a Cyclospora outbreak - Iowa, July 2013. MMWR Morb Mortal Wkly Rep. 2013 Aug 2. 62 (30):613-4. [QxMD MEDLINE Link].
de la Luz Galván-Ramírez M, Madriz-Elisondo AL, Ramírez CGT, de Jesús Romero Rameño J, de la O Carrasco DA, López MAC. Enteroparasitism and Risk Factors Associated with Clinical Manifestations in Children and Adults of Jalisco State in Western Mexico. Osong Public Health Res Perspect. 2019 Feb. 10 (1):39-48. [QxMD MEDLINE Link].
Giangaspero A, Gasser RB. Human cyclosporiasis. Lancet Infect Dis. 2019 Jul. 19 (7):e226-e236. [QxMD MEDLINE Link].
Li J, Wang Z, Karim MR, Zhang L. Detection of human intestinal protozoan parasites in vegetables and fruits: a review. Parasit Vectors. 2020 Jul 29. 13 (1):380. [QxMD MEDLINE Link].
Ortiz Pineda C, Temesgen TT, Robertson LJ. Multiplex Quantitative PCR Analysis of Strawberries from Bogotá, Colombia, for Contamination with Three Parasites. J Food Prot. 2020 Oct 1. 83 (10):1679-1684. [QxMD MEDLINE Link].
Giangaspero A, Gasser RB. Human cyclosporiasis. Lancet Infect Dis. 2019 Jul. 19 (7):e226-e236. [QxMD MEDLINE Link].
Fleming CA, Caron D, Gunn JE, Barry MA. A foodborne outbreak of Cyclospora cayetanensis at a wedding: clinical features and risk factors for illness. Arch Intern Med. 1998 May 25. 158(10):1121-5. [QxMD MEDLINE Link].
Hadjilouka A, Tsaltas D. Cyclospora Cayetanensis-Major Outbreaks from Ready to Eat Fresh Fruits and Vegetables. Foods. 2020 Nov 20. 9 (11):[QxMD MEDLINE Link].
Parija SC, Shivaprakash MR, Jayakeerthi SR. Evaluation of lacto-phenol cotton blue (LPCB) for detection of Cryptosporidium, Cyclospora and Isospora in the wet mount preparation of stool. Acta Trop. 2003 Mar. 85(3):349-54. [QxMD MEDLINE Link].
Parija SC, Prabhakar PK. Evaluation of lacto-phenol cotton blue for wet mount preparation of feces. J Clin Microbiol. 1995 Apr. 33(4):1019-21. [QxMD MEDLINE Link].
Bateman AC, Kim YJ, Guaracao AI, Mason JL, Klos RF, Warshauer DM. Performance and Impact of the BioFire FilmArray Gastrointestinal Panel on a Large Cyclospora Outbreak in Wisconsin, 2018. J Clin Microbiol. 2020 Jan 28. 58 (2):[QxMD MEDLINE Link].
Totton SC, O'Connor AM, Naganathan T, Martinez BAF, Vriezen ER, Torrence ME, et al. A scoping review of the detection, epidemiology and control of Cyclospora cayetanensis with an emphasis on produce, water and soil. Epidemiol Infect. 2021 Jan 28. 149:e49. [QxMD MEDLINE Link].
Bartosova B, Koudela B, Slana I. Detection of Cyclospora cayetanensis, Echinococcus multilocularis, Toxocara spp. and microsporidia in fresh produce using molecular methods: - A review. Food Waterborne Parasitol. 2021 Jun. 23:e00124. [QxMD MEDLINE Link].
Durigan M, Murphy HR, da Silva AJ. Dead-End Ultrafiltration and DNA-Based Methods for Detection of Cyclospora cayetanensis in Agricultural Water. Appl Environ Microbiol. 2020 Nov 10. 86 (23):[QxMD MEDLINE Link].
Tulipani S, Mezzetti B, Capocasa F, Bompadre S, Beekwilder J, de Vos CH, et al. Antioxidants, phenolic compounds, and nutritional quality of different strawberry genotypes. J Agric Food Chem. 2008 Feb 13. 56 (3):696-704. [QxMD MEDLINE Link].
Assurian A, Murphy H, Shipley A, Cinar HN, DA Silva A, Almeria S. Assessment of Commercial DNA Cleanup Kits for Elimination of Real-Time PCR Inhibitors in the Detection of Cyclospora cayetanensis in Cilantro. J Food Prot. 2020 Nov 1. 83 (11):1863-1870. [QxMD MEDLINE Link].
Connor BA, Shlim DR, Scholes JV, Rayburn JL, Reidy J, Rajah R. Pathologic changes in the small bowel in nine patients with diarrhea associated with a coccidia-like body. Ann Intern Med. 1993 Sep 1. 119(5):377-82. [QxMD MEDLINE Link].
Connor BA, Reidy J, Soave R. Cyclosporiasis: clinical and histopathologic correlates. Clin Infect Dis. 1999 Jun. 28(6):1216-22. [QxMD MEDLINE Link].
Ortega YR, Nagle R, Gilman RH, et al. Pathologic and clinical findings in patients with cyclosporiasis and a description of intracellular parasite life-cycle stages. J Infect Dis. 1997 Dec. 176(6):1584-9. [QxMD MEDLINE Link].
Verdier RI, Fitzgerald DW, Johnson WD Jr, Pape JW. Trimethoprim-sulfamethoxazole compared with ciprofloxacin for treatment and prophylaxis of Isospora belli and Cyclospora cayetanensis infection in HIV-infected patients. A randomized, controlled trial. Ann Intern Med. 2000 Jun 6. 132(11):885-8. [QxMD MEDLINE Link].
Chandra V, Torres M, Ortega YR. Efficacy of Wash Solutions in Recovering Cyclospora cayetanensis, Cryptosporidium parvum, and Toxoplasma gondii from Basil. J Food Prot. 2014 Aug. 77(8):1348-54. [QxMD MEDLINE Link].
Poulle ML, Bastien M, Richard Y, Josse-Dupuis É, Aubert D, Villena I, et al. Detection of Echinococcus multilocularis and other foodborne parasites in fox, cat and dog faeces collected in kitchen gardens in a highly endemic area for alveolar echinococcosis. Parasite. 2017. 24:29. [QxMD MEDLINE Link].
Zar FA, El-Bayoumi E, Yungbluth MM. Histologic proof of acalculous cholecystitis due to Cyclospora cayetanensis. Clin Infect Dis. 2001 Dec 15. 33(12):E140-1. [QxMD MEDLINE Link].
Calderón de la Barca AM, Castillo-Fimbres RS, Mejía-León ME, Quihui-Cota L, Ochoa-Leyva A, Aguayo-Patrón SV. Enteric parasitic infection disturbs bacterial structure in Mexican children with autoantibodies for type 1 diabetes and/or celiac disease. Gut Pathog. 2020. 12:37. [QxMD MEDLINE Link].

Media Gallery

Photomicrograph of a fresh stool sample prepared with a 10% formalin solution and stained with modified acid-fast stain. This image shows four Cyclospora cayetanensis oocysts with variable staining among the four oocysts. Courtesy of CDC/DPDx - Melanie Moser [https://phil.cdc.gov/Details.aspx?pid=7827].
Photomicrograph of a fresh stool sample prepared using a 10% formalin solution and stained with safranin. Three homogenously stained Cyclospora cayetanensis oocysts can be seen. Courtesy of CDC/DPDx - Melanie Moser [https://phil.cdc.gov/Details.aspx?pid=7828].
Life cycle of Cyclospora cayetanensis in pictorial form. Courtesy of CDC/DPDx [https://www.cdc.gov/parasites/cyclosporiasis/biology.html].

of 3

Table 1. Epidemiology of C cayetanensis *

Table 1. Epidemiology of C cayetanensis *

Pattern of Spread	Countries	Comments
Endemic	Bangladesh, Brazil, Chile, China, Cuba, Dominican Republic, Egypt, Guatemala, Haiti, India, Indonesia, Jordan, Mexico, Morocco, Nepal, Nigeria, Pakistan, Peru, Puerto Rico, Romania, Saudi Arabia, Tanzania, Thailand, Turkey, Venezuela, Viet Nam, Zimbabwe	Prevalence (1-15%†) varies significantly with the season and from year to year; children (≤ 9 y, most studies) account for 70-80% cases, which are typically asymptomatic (72-94%); asymptomatic disease is higher in older children (10-18 y) and adults (>18 y); infection rate in those with HIV is significantly higher than overall prevalence
International travel-related	Australia, Belgium, Czech Republic, Germany, Greece, Ireland, Italy, Japan, The Netherlands, Spain, Switzerland, United Kingdom, United States	≤4% returning travelers with diarrhea
Foodborne outbreaks	Canada, United States, Germany, Mexico	Canada/United States: raspberries, blackberries, mesclun, basil‡; Germany: lettuce imported from Southern France/Southern Italy; Mexico: watercress
Waterborne outbreaks	United States (Chicago), Nepal	14 cases of cyclosporiasis; tap water in medical dormitory, suspected source was contaminated water storage tank; 12 of 14 developed cyclosporiasis
* Community-based studies † Highest in spring and early summer ‡ Fresh produce. Raspberries, peas, or blackberries from Guatemala; mesclun (young salad greens, eg, spring mix, field greens, baby greens, gourmet salad mix) or lettuce from Peru or United States; basil from Mexico or United States.

Back to List

Author

Chinelo N Animalu, MD, MPH, FIDSA Associate Professor, Division of Infectious Diseases, Department of Internal Medicine, University of Tennessee Health Science Center College of Medicine; Physician, Department of Infectious Disease, University of Tennessee Methodist Physicians (UTMP), Methodist University Hospital

Chinelo N Animalu, MD, MPH, FIDSA is a member of the following medical societies: American College of Physicians, American Medical Association, Infectious Diseases Society of America, Memphis Medical Society, Tennessee Medical Association

Disclosure: Nothing to disclose.

Coauthor(s)

Jay R Patel, BA, BS MD Candidate, University of Tennessee Health Science Center College of Medicine

Jay R Patel, BA, BS is a member of the following medical societies: American Medical Association, Memphis Medical Society, Tennessee Medical Association

Disclosure: Nothing to disclose.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

John W King, MD Professor of Medicine, Chief, Section of Infectious Diseases, Director, Viral Therapeutics Clinics for Hepatitis, Louisiana State University School of Medicine in Shreveport; Consultant in Infectious Diseases, Overton Brooks Veterans Affairs Medical Center

John W King, MD is a member of the following medical societies: American Association for the Advancement of Science, American College of Physicians, American Federation for Medical Research, American Society for Microbiology, Association of Subspecialty Professors, Infectious Diseases Society of America, Sigma Xi, The Scientific Research Honor Society

Disclosure: Nothing to disclose.

Chief Editor

Pranatharthi Haran Chandrasekar, MBBS, MD Professor, Chief of Infectious Disease, Department of Internal Medicine, Wayne State University School of Medicine

Pranatharthi Haran Chandrasekar, MBBS, MD is a member of the following medical societies: American College of Physicians, American Society for Microbiology, International Immunocompromised Host Society, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Additional Contributors

Jeffrey D Band, MD, FACP, FIDSA Professor of Medicine, Oakland University William Beaumont School of Medicine; Health System Chair, Healthcare Epidemiology and International Medicine, Beaumont Health System; Former Chief of Infectious Diseases, Beaumont Hospital; Clinical Professor of Medicine, Wayne State University School of Medicine

Disclosure: Nothing to disclose.

William H Shoff, MD, DTM&H Former Director, PENN Travel Medicine; Former Associate Professor, Department of Emergency Medicine, Hospital of the University of Pennsylvania, University of Pennsylvania School of Medicine

William H Shoff, MD, DTM&H is a member of the following medical societies: American College of Physicians, American Society of Tropical Medicine and Hygiene, International Society of Travel Medicine, Society for Academic Emergency Medicine, Wilderness Medical Society

Disclosure: Nothing to disclose.

Acknowledgements

Amy J Behrman, MD Associate Professor, Department of Emergency Medicine, Director, Division of Occupational Medicine, University of Pennsylvania School of Medicine

Amy J Behrman, MD is a member of the following medical societies: American College of Occupational and Environmental Medicine

Disclosure: Nothing to disclose.

Suzanne Moore Shepherd, MD, MS, DTM&H, FACEP, FAAEM Associate Professor, Education Officer, Department of Emergency Medicine, Hospital of the University of Pennsylvania; Director of Education and Research, PENN Travel Medicine

Suzanne Moore Shepherd, MD, MS, DTM&H, FACEP, FAAEM is a member of the following medical societies: Alpha Omega Alpha, American Academy of Emergency Medicine, American Society of Tropical Medicine and Hygiene, International Society of Travel Medicine, Society for Academic Emergency Medicine, and Wilderness Medical Society

Disclosure: Nothing to disclose.