Progress on the epidemiological characteristics, detection techniques, and control strategies of Cyclospora cayetanensis

doi:10.12140/j.issn.1000-7423.2026.04.002

Abstract

Abstract:

Cyclospora cayetanensis is an emerging foodborne intestinal protozoan parasite that causes cyclosporiasis, a disease primarily characterized by persistent diarrhea. In recent years, it has become a major public health threat worldwide and is a pathogen under surveillance by FoodNet in the United States. The oocysts of C. cayetanensis become infective only after sporulation in the environment and are primarily transmitted via contaminated agricultural products and water sources. No direct human-to-human transmission has been documented to date. Cases of cyclosporiasis have been reported in at least 54 countries globally, with large-scale foodborne outbreaks occurring repeatedly in the United States, Canada, and other regions. The 2026 cyclosporiasis outbreak in the United States was the most severe on record, with 13 895 reported indigenous confirmed cases and over 10 455 suspected cases (as of August 11, 2026). In China, the first case of cyclosporiasis was reported in 1995, and sporadic human infections have been documented across multiple regions with significant geographical variation. However, due to the absence of a national surveillance network, baseline data at the national level remain lacking, and the epidemiological characteristics of the disease in China are still unclear. This article reviews the research progress on the etiological characteristics, clinical manifestations, epidemiology, detection techniques, and surveillance systems of C. cayetanensis, aiming to provide a reference for surveillance, risk assessment and prevention and control strategies for cyclosporiasis.

Key words: Cyclospora cayetanensis, Cyclosporiasis, Epidemiology, Detection techniques, Foodborne parasitic diseases

CLC Number:

R382.3

HULALAI Hader, ZUO Qingqiu, GULIBANU Aimaier, LI Shizhu, ZHENG Bin, SHEN Yujuan. Progress on the epidemiological characteristics, detection techniques, and control strategies of Cyclospora cayetanensis[J]. CHINESE JOURNAL OF PARASITOLOGY AND PARASITIC DISEASES, 2026, 44(4): 468-476.

Figures/Tables 3

References 80

[1]	Hadjilouka A, Tsaltas D. Cyclospora cayetanensis: major outbreaks from ready to eat fresh fruits and vegetables[J]. Foods, 2020, 9(11): 1703.
[2]	Giangaspero A, Gasser RB. Human cyclosporiasis[J]. Lancet Infect Dis, 2019, 19(7): e226-e236.
[3]	Totton SC, O’Connor AM, Naganathan T, et al. A review of Cyclospora cayetanensis in animals[J]. Zoonoses Public Heal, 2021, 68(8): 861-867.
[4]	李俊强. 人、牛环孢子虫病流行病学调查及分子生物学研究[D]. 郑州: 河南农业大学, 2014: 1.
	Li JQ. Epidemiology investigation and molecular biology of Cyclospora sp. from human and cattle[D]. Zhengzhou: Henan Agricultural University, 2014: 1. (in Chinese)
[5]	Hall RL, Jones JL, Hurd S, et al. Population-based active surveillance for Cyclospora infection: United States, foodborne diseases active surveillance network (FoodNet), 1997-2009[J]. Clin Infect Dis, 2012, 54(Suppl 5): S411-S417.
[6]	Chacín-Bonilla L. Epidemiology of Cyclospora cayetanensis: a review focusing in endemic areas[J]. Acta Trop, 2010, 115(3): 181-193.
[7]	Centers for Disease Control and Prevention. Surveillance of cyclosporiasis[EB/OL]. (2026-08-11)[2026-08-16]. https://www.cdc.gov/cyclosporiasis/php/surveillance/index.html.
[8]	Feng KL, Guo YQ, Li N, et al. Cyclospora in humans, animals, fresh produce and water in China: implications for host specificity of Cyclospora species and zoonotic transmission of C. cayetanensis[J]. One Heal Adv, 2025, 3(1): 24.
[9]	沈玉娟, 姜岩岩, 曹建平. 我国介水传播肠道原虫病流行现状与防控策略[J]. 中国寄生虫学与寄生虫病杂志, 2021, 39(1): 8-19.
	Shen YJ, Jiang YY, Cao JP. Prevalence of waterborne intestinal protozoosis and strategies for its prevention and control strategies in China[J]. Chin J Parasitol Parasit Dis, 2021, 39(1): 8-19. (in Chinese)
[10]	中国疾病预防控制中心寄生虫病预防控制所. 圆孢子虫病[EB/OL]. (2024-08-24)[2026-08-16]. https://www.ipd.org.cn/know25.html.
	National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention. Cyclosporiasis[EB/OL]. (2024-08-24)[2026-08-16]. https://www.ipd.org.cn/know25.html. (in Chinese)
[11]	Li JQ, Cui ZH, Qi M, et al. Advances in cyclosporiasis diagnosis and therapeutic intervention[J]. Front Cell Infect Microbiol, 2020, 10: 43.
[12]	Li JQ, Wang RJ, Chen YC, et al. Cyclospora cayetanensis infection in humans: biological characteristics, clinical features, epidemiology, detection method and treatment[J]. Parasitology, 2020, 147(2): 160-170.
[13]	Almeria S, Cinar HN, Dubey JP. Cyclospora cayetanensis and cyclosporiasis: an update[J]. Microorganisms, 2019, 7(9): 317.
[14]	Centers for Disease Control and Prevention. Three of a kind: CDC researchers find Cyclospora is not just a single species[EB/OL]. (2024-08-15).[2026-08-16]. https://www.cdc.gov/advanced-molecular-detection/php/success-stories/cyclospora.html
[15]	Barratt JLN, Shen J, Houghton K, et al. Cyclospora cayetanensis comprises at least 3 species that cause human cyclosporiasis[J]. Parasitology, 2023, 150(3): 269-285.
[16]	李俊强. 卡耶塔环孢子虫分离株群体遗传结构特征及常见果蔬携带情况研究[D]. 郑州: 河南农业大学, 2018: 5.
	Li JQ. Population genetic structure of Cyclospora cayetanensis isolates and carrying status on the common vegetables and fruits[D]. Zhengzhou: Henan Agricultural University, 2018: 5. (in Chinese)
[17]	Dubey JP, Khan A, Rosenthal BM. Life cycle and transmission of Cyclospora cayetanensis: knowns and unknowns[J]. Microorganisms, 2022, 10(1): 118.
[18]	Centers for Disease Control and Prevention. Cyclosporiasis [EB/OL]. (2019-04-10)[2026-08-16]. https://www.cdc.gov/dpdx/cyclosporiasis/index.html#1.
[19]	Gabain IL, Kadia BM, Nurfadilah M, et al. Systematic review to evaluate the potential association of maternal and/or child intestinal parasitic protozoal infection with birth outcomes and linear growth faltering[J]. Adv Parasitol, 2025, 129: 145-185.
[20]	Ramezanzadeh S, Beloukas A, Pagheh AS, et al. Global burden of Cyclospora cayetanensis infection and associated risk factors in people living with HIV and/or AIDS[J]. Viruses, 2022, 14(6): 1279.
[21]	Mathison BA, Pritt BS. Cyclosporiasis: updates on clinical presentation, pathology, clinical diagnosis, and treatment[J]. Microorganisms, 2021, 9(9): 1863.
[22]	Chen YC, Qin ZY, Li JQ, et al. The global prevalence of Cyclospora cayetanensis infection: a systematic review, meta-analysis, and meta-regression[J]. Acta Trop, 2024, 253: 107175.
[23]	Giangaspero A, Papini RA, Berrilli F, et al. A narrative review of Cyclospora in Europe: unravelling the epidemiology and public health implications of cyclosporiasis[J]. Food Control, 2027, 191: 112381.
[24]	Chacin-Bonilla L, Santin M. Cyclospora cayetanensis infection in developed countries: potential endemic foci[J]. Microorganisms, 2023, 11(3): 540.
[25]	Zhang BX, Yu H, Zhang LL, et al. Prevalence survey on Cyclospora cayetanensis and Cryptosporidium spp. in diarrhea cases in Yunnan Province[J]. Chin J Parasitol Parasit Dis, 2002, 20(2): 106-108.
[26]	Wang KX. Cyclospore cayetanensis in Anhui, China[J]. World J Gastroenterol, 2002, 8(6): 1144.
[27]	Zhou Y, Lv B, Wang Q, et al. Prevalence and molecular characterization of Cyclospora cayetanensis, Henan, China[J]. Emerg Infect Dis, 2011, 17(10): 1887-1890.
[28]	Li JQ, Chang YK, Shi KE, et al. Multilocus sequence typing and clonal population genetic structure of Cyclospora cayetanensis in humans[J]. Parasitology, 2017, 144(14): 1890-1897.
[29]	Jiang YY, Yuan ZY, Liu H, et al. Intestinal protozoan infections in patients with diarrhea - Shanghai municipality, Zhenjiang City, and Danyang City, China, 2011-2015 and 2019-2021[J]. China CDC Wkly, 2022, 4(8): 143-147.
[30]	Liu H, Shen YJ, Yin JH, et al. Prevalence and genetic characterization of Cryptosporidium, Enterocytozoon, Giardia and Cyclospora in diarrheal outpatients in China[J]. BMC Infect Dis, 2014, 14: 25.
[31]	Jiang YY, Yuan ZY, Zang GQ, et al. Cyclospora cayetanensis infections among diarrheal outpatients in Shanghai: a retrospective case study[J]. Front Med, 2018, 12(1): 98-103.
[32]	Li J, Ren YJ, Chen HY, et al. Risk evaluation of pathogenic intestinal protozoa infection among laboratory macaques, animal facility workers, and nearby villagers from one health perspective[J]. Front Vet Sci, 2021, 8: 696568.
[33]	Zhao W, Yao L, Zhuang M, et al. A baseline epidemiological study of the co-infection of enteric protozoans with human immunodeficiency virus among men who have sex with men from Northeast China[J]. PLoS Negl Trop Dis, 2022, 16(9): e0010712.
[34]	Liu H, Ni HX, Liu SK, et al. First report on occurrence and genotypes of Enterocytozoon bieneusi, Cryptosporidium spp. and Cyclospora cayetanensis from diarrheal outpatients in Ningbo, Southeast China[J]. Microb Pathog, 2023, 174: 105952.
[35]	王雅雪, 简金花, 刘华, 等. 云南省洱源县人群芽囊原虫和卡耶塔环孢子虫感染情况及其分子特征[J]. 中国寄生虫学与寄生虫病杂志, 2024, 42(2): 242-250.
	Wang YX, Jian JH, Liu H, et al. Prevalence and molecular characteristics of blastocystis and Cyclospora cayetanensis infections among residents in Eryuan County, Yunnan Province[J]. Chin J Parasitol Parasit Dis, 2024, 42(2): 242-250. (in Chinese)
[36]	Ghorbani A, Menati R, Kakian F, et al. Prevalence and associated risk factors of Cyclospora cayetanensis in immunocompromised patients: a systematic review and meta-analysis[J]. Can J Infect Dis Med Microbiol, 2025, 2025: 8837624.
[37]	Ortega YR, Sanchez R. Update on Cyclospora cayetanensis, a food-borne and waterborne parasite[J]. Clin Microbiol Rev, 2010, 23(1): 218-234.
[38]	Centers for Disease Control and Prevention. Update: outbreaks of cyclosporiasis: United States and Canada, 1997[J]. Morb Mortal Wkly Rep, 1997, 46(23): 521-523.
[39]	Herwaldt BL, Ackers ML. An outbreak in 1996 of cyclosporiasis associated with imported raspberries[J]. N Engl J Med, 1997, 336(22): 1548-1556.
[40]	Centers for Disease Control and Prevention. Cyclosporiasis surveillance: United States, 2011-2015[J]. Morb Mortal Wkly Rep, 2018, 68(3): 1-16.
[41]	Buss BF, Joshi MV, O’Keefe AL, et al. Regional investigation of a cyclosporiasis outbreak linked to imported romaine lettuce: Nebraska and Iowa, June-August 2013[J]. Epidemiol Infect, 2016, 144(9): 1807-1817.
[42]	Rabold JG, Hoge CW, Shlim DR, et al. Cyclospora outbreak associated with chlorinated drinking water[J]. Lancet, 1994, 344(8933): 1360-1361.
[43]	Baldursson S, Karanis P. Waterborne transmission of protozoan parasites: review of worldwide outbreaks-an update 2004-2010[J]. Water Res, 2011, 45(20): 6603-6614.
[44]	Aksoy U, Akisu C, Sahin S, et al. First reported waterborne outbreak of cryptosporidiosis with Cyclospora co-infection in Turkey[J]. Euro Surveill, 2007, 12(2): E070215.4.
[45]	Bourli P, Eslahi AV, Tzoraki O, et al. Waterborne transmission of protozoan parasites: a review of worldwide outbreaks-an update 2017-2022[J]. J Water Health, 2023, 21(10): 1421-1447.
[46]	Centers for Disease Control and Prevention. Outbreak of cyclosporiasis [EB/OL]. (1998-10-02)[2026-08-16]. https://www.cdc.gov/mmwr/preview/mmwrhtml/00055016.htm.
[47]	Lopez AS, Dodson DR, Arrowood MJ, et al. Outbreak of cyclosporiasis associated with basil in Missouri in 1999[J]. Clin Infect Dis, 2001, 32(7): 1010-1017.
[48]	Ho AY, Lopez AS, Eberhart MG, et al. Outbreak of cyclosporiasis associated with imported raspberries, Philadelphia, Pennsylvania, 2000[J]. Emerg Infect Dis, 2002, 8(8): 783-788.
[49]	Döller PC, Dietrich K, Filipp N, et al. Cyclosporiasis outbreak in Germany associated with the consumption of salad[J]. Emerg Infect Dis, 2002, 8(9): 992-994.
[50]	Hoang LM, Fyfe M, Ong C, et al. Outbreak of cyclosporiasis in British Columbia associated with imported Thai basil[J]. Epidemiol Infect, 2005, 133(1): 23-27.
[51]	Centers for Disease Control and Prevention. Outbreak of cyclosporiasis associated with snow peas: Pennsylvania, 2004[J]. Morb Mortal Wkly Rep, 2004, 53(37): 876-878.
[52]	Gibbs RA, Nanyonjo R, Pingault NM, et al. An outbreak of Cyclospora infection on a cruise ship[J]. Epidemiol Infect, 2013, 141(3): 508-516.
[53]	Morton V, Meghnath K, Gheorghe M, et al. Use of a case-control study and control bank to investigate an outbreak of locally acquired cyclosporiasis in Canada, 2016[J]. Can Commun Dis Rep, 2019, 45(9): 225-229.
[54]	Centers for Disease Control and Prevention. Notes from the field:cyclosporiasis cases associated with dining at a Mediterranean-style restaurant chain-Texas, 2017[EB/OL]. (2018-06-01)[2026-08-16]. https://www.cdc.gov/mmwr/volumes/67/wr/mm6721a5.htm.
[55]	Centers for Disease Control and Prevention. Notes from the field: multiple cyclosporiasis outbreaks-United States[EB/OL]. (2018-10-05)[2026-08-16]. https://www.cdc.gov/mmwr/volumes/67/wr/mm6739a6.htm.
[56]	Food and Drug Administration. Outbreak investigation of Cyclospora: bagged salads[EB/OL]. (2020-09-25)[2026-08-16]. https://www.fda.gov/food/outbreaks-foodborne-illness/investigations-foodborne-illness-outbreaks.
[57]	Centers for Disease Control and Prevention. Outbreak of cyclosporiasis among patrons of a Mexican-style restaurant-Limestone County, Alabama, 2025[J]. Morb Mortal Wkly Rep, 2025, 74(13): 217-221
[58]	Ma A, Mathison BA, Couturier MR. Shedding new light on Cyclospora: how the use of ultraviolet fluorescence microscopy can improve diagnosis of cyclosporiasis[J]. J Clin Microbiol, 2025, 63(1): e0108424.
[59]	Quintero-Betancourt W, Peele ER, Rose JB. Cryptosporidium parvum and Cyclospora cayetanensis: a review of laboratory methods for detection of these waterborne parasites[J]. J Microbiol Methods, 2002, 49(3): 209-224.
[60]	Xue NY, Wang HT, Hou QY, et al. Investigation of Cyclospora spp. in farmed fur animals based on PCR-RFLP[J]. Vet Parasitol, 2025, 334: 110416.
[61]	Eberhard ML, Pieniazek NJ, Arrowood MJ. Laboratory diagnosis of Cyclospora infections[J]. Arch Pathol Lab Med, 1997, 121(8): 792-797.
[62]	孙春雪, 钱艳琼, 李渊, 等. 环孢子虫分子生物学检测研究进展[J]. 中国病原生物学杂志, 2019, 14(5): 610-613.
	Sun CX, Qian YQ, Li Y, et al. Advances in molecular biological detection of Cyclospora[J]. Chin J Parasitol Parasit Dis, 2019, 14(5): 610-613. (in Chinese)
[63]	Verweij JJ, Laeijendecker D, Brienen EA, et al. Detection of Cyclospora cayetanensis in travellers returning from the tropics and subtropics using microscopy and real-time PCR[J]. Int J Med Microbiol, 2003, 293(2-3): 199-202.
[64]	Qin Z, Wang Y, Sun M, et al. Development of a field-deployable RPA-CRISPR/Cas12a assay for the detection of Cyclospora cayetanensis in human feces[J]. Parasit Vectors, 2025, 19(1): 4.
[65]	Bruno JG. Revelation of DNA aptamer sequences that bind Cyclospora cayetanensis[J]. J Microbiol Methods, 2026, 242: 107410.
[66]	Robertson LJ, Gjerde B, Campbell AT. Isolation of Cyclospora oocysts from fruits and vegetables using lectin-coated paramagnetic beads[J]. J Food Prot, 2000, 63(10): 1410-1414.
[67]	Shields JM, Lee MM, Murphy HR. Use of a common laboratory glassware detergent improves recovery of Cryptosporidium parvum and Cyclospora cayetanensis from lettuce, herbs and raspberries[J]. Int J Food Microbiol, 2012, 153(1-2): 123-128.
[68]	Food and Drug Administration. BAM chapter 19b: molecular detection of Cyclospora cayetanensis in fresh produce using real-time PCR[EB/OL]. (2026-06-08)[2026-08-16]. https://www.fda.gov/food/laboratory-methods-food/bam-chapter-19b-molecular-detection-cyclospora-cayetanensis-fresh-produce-using-real-time-pcr.
[69]	Shapiro K, Kim M, Rajal VB, et al. Simultaneous detection of four protozoan parasites on leafy greens using a novel multiplex PCR assay[J]. Food Microbiol, 2019, 84: 103252.
[70]	Temesgen TT, Robertson LJ, Tysnes KR. A novel multiplex real-time PCR for the detection of Echinococcus multilocularis, Toxoplasma gondii, and Cyclospora cayetanensis on berries[J]. Food Res Int, 2019, 125: 108636.
[71]	el-Karamany EM, Zaher TI, el-Bahnasawy MM. Role of water in the transmission of cyclosporiasis in Sharkia Governorate, Egypt[J]. J Egypt Soc Parasitol, 2005, 35(3): 953-962.
[72]	Durigan M, Murphy HR, da Silva AJ. Dead-end ultrafiltration and DNA-based methods for detection of Cyclospora cayetanensis in agricultural water[J]. Appl Environ Microbiol, 2020, 86(23): e01533-20.
[73]	Durigan M, Ewing-Peeples L, Almeria S, et al. Detection of Cyclospora cayetanensis in food and water samples: optimized protocols for specific and sensitive molecular methods from a regulatory agency perspective[J]. J Food Prot, 2024, 87(7): 100291.
[74]	Foodborne Diseases Active Surveillance Network. About FoodNet[EB/OL]. (2026-04-28)[2026-08-16]. https://www.cdc.gov/foodnet/about/index.html.
[75]	Foodborne Diseases Active Surveillance Network. Pathogen surveillance tool guide[EB/OL]. (2025-02-03)[2026-08-16]. https://www.cdc.gov/foodnet/data/pathogen-surveillance.html.
[76]	Centers for Disease Control and Prevention. Clinical overview of cyclosporiasis[EB/OL]. (2024-02-29)[2026-08-16]. https://www.cdc.gov/cyclosporiasis/hcp/clinical-overview/index.html.
[77]	Hezema NN, Eltarahony MM, Afifi H, et al. Therapeutic potential of greenly synthesized selenium nanoparticles against experimental cyclosporiasis[J]. Sci Rep, 2025, 15(1): 30057.
[78]	Food and Drug Administration. Cyclospora prevention, response and research action plan[EB/OL]. (2023-06-30)[2026-08-16]. https://www.fda.gov/food/foodborne-pathogens/cyclospora-prevention-response-and-research-action-plan.
[79]	Centers for Disease Control and Prevention. Preventing cyclosporiasis[EB/OL]. (2026-08-07)[2026-08-16]. https://www.cdc.gov/cyclosporiasis/prevention/.
[80]	Food and Drug Administration. Cyclosporiasis and fresh produce [EB/OL]. (2022-11-18)[2026-08-16]. https://www.fda.gov/food/foodborne-pathogens/cyclospora-and-fresh-produce.

分/类	亚组	样本量/份	阳性数/份	感染率/%
按地区	非洲	11 068	606	5.90
	美洲	56 525	1 720	4.80
	亚洲	83 481	3 261	3.10
	欧洲	15 537	49	0.30
按收入水平	低收入	921	83	7.60
	中低收入	48 852	3 280	4.80
	中高收入	99 419	2 194	2.90
	高收入	17 419	79	0.40

地区	调查人群	检测方法	样本量/份	阳性数/例	感染率/%	年份	参考文献
云南	腹泻患者	镜检	378	15	4	1997—2000	[25]
安徽	混合人群	镜检	610	14	2.3	2001	[26]
河南	混合人群	镜检	11 554	81	0.7	2007—2009	[27]
河南	腹泻患者	PCR	6 579	76	1.2	2011—2015	[28]
上海、江苏镇江	腹泻患者	PCR	5 341	13	0.2	2011—2015、2019—2021	[29]
上海	腹泻患者	PCR	252	0	0	2012—2013	[30]
上海	腹泻患者	PCR	291	5	1.7	2013	[31]
广西	腹泻患者	PCR	50	5	10	2015	[32]
黑龙江	腹泻患者	PCR	601	7	1.2	2016—2017	[33]
浙江温州	腹泻患者	PCR	489	3	0.6	2019	[34]
云南	腹泻患者	PCR	100	2	2	2022	[35]

年份	主要发生地区	病例数	主要关联食品	参考文献
1996	美国、加拿大	1 465	覆盆子	[39]
1997	美国、加拿大	1 021	覆盆子	[38]
1998	加拿大	192	覆盆子	[46]
1999	美国	62	鸡肉意面、番茄罗勒、蔬菜意面沙拉	[47]
2000	美国	54	覆盆子	[48]
2000	德国	34	沙拉、绿叶蔬菜和香草	[49]
2001	加拿大	17	罗勒	[50]
2004	美国	50	雪豆	[51]
2010	澳大利亚（邮轮）	73	尚未确定	[52]
2013	美国	631	香菜和罗马生菜	[41]
2016	加拿大	87	黑莓	[53]
2017	美国	20	青葱	[54]
2018	美国	761	预包装蔬菜盘和沙拉	[55]
2020	美国	701	袋装混合沙拉	[56]
2023	美国	47	香菜	[57]
2026^a	美国	> 13 895	冰山生菜	[7]