Cyclospora Infection Research Articles

Novel insights on the genetic population structure of human-infecting Cyclospora spp. and evidence for rapid subtype selection among isolates from the USA

Human-infecting Cyclospora was recently characterized as three species, two of which (C. cayetanensis and C. ashfordi) are currently responsible for all known human infections in the USA, yet much remains unknown about the genetic structure within these two species. Here, we investigate Cyclospora genotyping data from 2018 through 2022 to ascertain if there are temporal patterns in the genetic structure of Cyclospora parasites that cause infections in US residents from year to year. First, we investigate three levels of genetic characterization: species, subpopulation, and strain, to elucidate annual trends in Cyclospora infections. Next, we determine if shifts in genetic diversity can be linked to any of the eight loci used in our Cyclospora genotyping approach. We observed fluctuations in the abundance of Cyclospora types at the species and subpopulation levels, but no significant temporal trends were identified; however, we found recurrent and sporadic strains within both C. ashfordi and C. cayetanensis. We also uncovered major shifts in the mitochondrial genotypes in both species, where there was a universal increase in abundance of a specific mitochondrial genotype that was relatively abundant in 2018 but reached near fixation (was observed in over 96% of isolates) in C. ashfordi by 2022. Similarly, this allele jumped from 29% to 82% relative abundance of isolates belonging to C. cayetanensis. Overall, our analysis uncovers previously unknown temporal-genetic patterns in US Cyclospora types from 2018 through 2022 and is an important step to presenting a clearer picture of the factors influencing cyclosporiasis outbreaks in the USA.

Factors associated with Cyclospora infection in a Venezuelan community: extreme poverty and soil transmission relate to cyclosporiasis.

Transmission dynamics of Cyclospora cayetanensis in endemic areas and the factors associated with soil contamination remain unclear. The effects of environmental factors on Cyclospora have been insufficiently studied, particularly in South America, thus a Venezuelan community was studied to profile risk factors for infection. A cross-sectional stool survey of 732 individuals was conducted. For Cyclospora screening, an acid-fast-stained smear of formalin-ethyl acetate concentrate and ultraviolet (UV) epifluorescence examination of a wet mount were used. Water (n=14), soil (n=50) and produce (n=77) samples were collected, processed and examined by UV epifluorescence. Data were analysed using multivariate logistic regression. Cyclospora infections were identified in 73 (9.9%) subjects. Variables associated with the infection were age ≤10y (odds ratio [OR] 14), hut living (OR 5), well water use (OR 18.5), drinking untreated water (OR 7.6), toilet absence (OR 8), having contact with faeces-contaminated soil (OR 4) and poultry exposure (OR 3). Infections (63%) were clustered in 25 huts. Oocysts were identified in 28.6%, 18% and 3.9% of the water, soil and produce samples, respectively. There was an explicit association of Cyclospora infection with extreme poverty and soil transmission reflecting the household socio-economic correlate of cyclosporiasis in this community.

Cyclosporiasis in immunocompetent and immunocompromised patients - A Twelve years experience from a tertiary care centre in Northern India.

Cyclosporiasis is an emerging enteric coccidian parasitic disease worldwide, caused by the parasite Cyclospora cayetanensis. There is scanty data from India, especially among immunocompetent patients. The aim is to evaluate the occurrence of Cyclosporiasis in immunocompetent and immunocompromised patients. It is a prospective cohort study conducted from June 2006 to May 2018 at our tertiary care center. Stool samples were collected from the 900 patients with diarrhea (both immunocompetent and immunocompromised) and 170 healthy controls to look for Cyclospora by modified Kinyoun staining. Mann-Whitney U test/Fisher exact test were used for statistical analysis. Oocysts of C. cayetanensis were detected in 10/900 patients and none of the healthy controls. The median age of patients was 38.5 years (10-65 years) and males (6/10) outnumbered the females in harboring the parasite. Eight patients were immunocompromised (five postrenal transplant cases and one-one patient each with HIV, non-Hodgkin's lymphoma, and juvenile polyarthritis), and two patients were immunocompetent. Cyclospora infection was more common in immunocompromised patients (8/300, 2.67%) than the immunocompetent patients (2/600, 0.33%); P < 0.001. Eight patients responded well to trimethoprim-sulfamethoxazole, one died, and one was lost to follow-up. Coinfection with Cryptosporidium spp. was seen in one patient. Cyclospora causes diarrhea in both immunocompromised and immunocompetent persons. Its burden may be underestimated due to a lack of awareness and appropriate diagnostic methods. Special staining techniques are important for diagnosis as they may be missed by routine microscopy.

Silver nanoparticles as a therapeutic agent in experimental cyclosporiasis

Cyclosporiasis is an emerging worldwide infection caused by an obligate intracellular protozoan parasite, Cyclospora cayetanensis. In immunocompetent patients, it is mainly manifested by self-limited diarrhea, which is persistent and may be fatal in immunocompromised patients. The standard treatment for cyclosporiasis is a combination of two antibiotics, trimethoprim and sulfamethoxazole. Gastrointestinal, haematologic and renal side effects were reported with this combination. Moreover, sulfa allergy, foetal anomalies and recurrence were recorded with no alternative drug treatment option. In this study, silver nanoparticles were chemically synthesized to be evaluated for the first time for their anti-cyclospora effects in both immunocompetent and immunosuppressed experimental mice in comparison to the standard treatment. The effect of silver nanoparticles was assessed through studying stool oocyst load, oocyst viability, ultrastructural changes in oocysts, and estimation of serum gamma interferon. Toxic effect of the therapeutic agents was evaluated by measuring liver enzymes, urea and creatinine in mouse sera. Results showed that silver nanoparticles had promising anti-cyclospora potentials. The animals that received these nanoparticles showed a statistically significant decrease in the oocyst burden and number of viable oocysts in stool and a statistically significant increase in serum gamma interferon in comparison to the corresponding group receiving the standard treatment and to the infected non-treated control group. Scanning electron microscopic examination revealed mutilated oocysts with irregularities, poring and perforations. Biochemical results showed no evidence of toxicity of silver nanoparticles, as the sera of the mice showed a statistically non-significant decrease in liver enzymes in immunocompetent subgroups, and a statistically significant decrease in immunosuppressed subgroups. Furthermore, a statistically non-significant decrease in urea and creatinine was recorded in all subgroups. Thus, silver nanoparticles proved their effectiveness against Cyclospora infection, and this will draw the attention to its use as an alternative to the standard therapy.

Cyclospora Cayetanensis Presence in the Environment—A Case Study in the Chicago Metropolitan Area

Cyclospora cayetanensis is an emerging foodborne protozoan pathogen. Similar to other gastrointestinal illnesses, cyclosporiasis causes prolonged diarrhea. Unlike Cryptosporidium, Cyclospora oocysts are not infective when they are shed by infected individuals. Oocysts mature in the environment for 7–10 days before sporulating. Little is known about how C. cayetanensis is transported in the environment and which factors inhibit or promote sporulation. Water and fresh produce, such as leafy greens and berries, are common sources of infection. Contact with soil has also been correlated with Cyclospora infection. In addition to acting as a vector to transport oocysts from the environment to the body, water and soil may be important reservoirs to not only allow C. cayetanensis to persist, but also transport the oocysts from one location to another. This study examined a snapshot of an urban area near Chicago where human waste sporadically enters the environment via combined sewer outfalls (CSO). A total of 61 samples were collected from three CSO discharge events. Most of the 21 positive samples were wildlife feces (n = 13), and a few were soil (n = 7). There was one positive water sample. PCR analysis of soil, water, and wildlife feces indicated the presence of C. cayetanensis in the environment, suggesting likely transport of oocysts by wildlife. Given the emerging threat of cyclosporiasis, additional studies are needed to confirm and expand this case study.

Preliminary Incidence and Trends of Infections with Pathogens Transmitted Commonly Through Food - Foodborne Diseases Active Surveillance Network, 10 U.S. Sites, 2015-2018.

Foodborne diseases represent a major health problem in the United States. The Foodborne Diseases Active Surveillance Network (FoodNet) of CDC's Emerging Infections Program monitors cases of laboratory-diagnosed infection caused by eight pathogens transmitted commonly through food in 10 U.S. sites.* This report summarizes preliminary 2018 data and changes since 2015. During 2018, FoodNet identified 25,606 infections, 5,893 hospitalizations, and 120 deaths. The incidence of most infections is increasing, including those caused by Campylobacter and Salmonella, which might be partially attributable to the increased use of culture-independent diagnostic tests (CIDTs). The incidence of Cyclospora infections increased markedly compared with 2015-2017, in part related to large outbreaks associated with produce (1). More targeted prevention measures are needed on produce farms, food animal farms, and in meat and poultry processing establishments to make food safer and decrease human illness.

Cyclosporiasis Surveillance - United States, 2011-2015.

Problem/ConditionCyclosporiasis is an intestinal illness caused by the parasite Cyclospora cayetanensis, which is transmissible by ingestion of fecally contaminated food or water. Cyclosporiasis is most common in tropical and subtropical regions of the world. In the United States, foodborne outbreaks of cyclosporiasis have been linked to various types of imported fresh produce (e.g., basil, raspberries, and snow peas). Validated molecular typing tools, which could facilitate detection and investigation of outbreaks, are not yet available for C. cayetanensis.Period Covered2011–2015.Description of SystemCDC has been conducting national surveillance for cyclosporiasis since it became a nationally notifiable disease in January 1999. As of 2015, cyclosporiasis was a reportable condition in 42 states, the District of Columbia, and New York City (NYC). Health departments voluntarily notify CDC of cases of cyclosporiasis through the National Notifiable Diseases Surveillance System and submit additional case information using the CDC cyclosporiasis case report form or the Cyclosporiasis National Hypothesis Generating Questionnaire (CNHGQ).ResultsFor the 2011–2015 surveillance period, CDC was notified by 37 states and NYC of 2,207 cases of cyclosporiasis, including 1,988 confirmed cases (90.1%) and 219 probable cases (9.9%). The annual number of reported cases ranged from 130 in 2012 to 798 in 2013; the annual population-adjusted incidence rate ranged from 0.05 cases per 100,000 persons in 2012 to 0.29 in 2013. A total of 415 patients (18.8%) had a documented history of international travel during the 14 days before illness onset, 1,384 (62.7%) did not have a history of international travel, and 408 (18.5%) had an unknown travel history. Among the 1,359 domestically acquired cases with available information about illness onset, 1,263 (92.9%) occurred among persons who became ill during May–August. During 2011–2015, a total of 10 outbreaks of cyclosporiasis associated with 438 reported cases were investigated; a median of 21 cases were reported per outbreak (range: eight to 162). A food vehicle of infection (i.e., a food item or ingredient thereof) was identified (or suspected) for at least five of the 10 outbreaks; the food vehicles included a berry salad (one outbreak), cilantro imported from Mexico (at least three outbreaks), and a prepackaged salad mix from Mexico (one outbreak).InterpretationCyclosporiasis continues to be a U.S. public health concern, with seasonal increases in reported cases during spring and summer months. The majority of cases reported for this 5-year surveillance period occurred among persons without a history of international travel who became ill during May–August. Many of the seemingly sporadic domestically acquired cases might have been associated with identified or unidentified outbreaks; however, those potential associations were not detected using the available epidemiologic information. Prevention of cases and outbreaks of cyclosporiasis in the United States depends on outbreak detection and investigation, including identification of food vehicles of infection and their sources, which could be facilitated by the availability of validated molecular typing tools.Public Health ActionSurveillance for cases of cyclosporiasis and efforts to develop and validate molecular typing tools should remain U.S. public health priorities. During periods and seasons when increased numbers of domestically acquired cases are reported, the CNHGQ should be used to facilitate outbreak detection and hypothesis generation. Travelers to areas of known endemicity (e.g., in the tropics and subtropics) should follow food and water precautions similar to those for other enteric pathogens but should be advised that use of routine chemical disinfection or sanitizing methods is unlikely to kill C. cayetanensis. Health care providers should consider the possibility of Cyclospora infection in persons with persistent or remitting-relapsing diarrheal illness, especially for persons with a history of travel to areas of known endemicity or with symptom onset during spring or summer. If indicated, laboratory testing for Cyclospora should be explicitly requested because such testing is not typically part of routine examinations for ova and parasites and is not included in all gastrointestinal polymerase chain reaction panels. Newly identified cases of cyclosporiasis should be promptly reported to state or local public health authorities, who are encouraged to notify CDC of the cases.

Morphological and molecular identification of Cyclospora species in sheep and goat at Tamil Nadu, India.

A total of 281 fresh fecal samples (65 sheeps and 216 goats) were examined for the presence of Cyclospora species in Tamil Nadu from October 2017 to April 2018. All the faecal samples were examined by direct smear method, saturated sucrose floatation technique and modified Ziehl-Neelsen staining method and it was confirmed-at genus level with PCR technique. Overall prevalence of Cyclospora infection in-small ruminant was 2.14%. The prevalence of Cyclospora species in sheep and goat was 3.08 and 1.85% respectively. Cyclospora oocyst was observed mostly during winter season (Dec-Feb) with 7.14% followed by summer (March and April) and Northeast mansoon (October and November) with 1.67 and 1.66% respectively. The oocyst detected from faecal sample through conventional faecal examination was confirmed by PCR.

Parasites in Duodenal Aspirate using Endoscopy in Sohag, Egypt

Background and study aim:Gastrointestinal parasites cause infectious diseases. Parasitic infection of duodenum is a relevant cause of its inflammation and appearance of upper GIT manifestation, especially in developing countries. Examination of duodenal aspirates can be very helpful in diagnosing intestinal infection because it eliminates some of the problems inherent in stool examination. The aim of this study was to estimate the prevalence of parasites in duodenal aspirate obtained by upper gastrointestinal tract endoscopy. Subjects and methods: This cross-sectional study was conducted from March 2017 to March 2018 in sohag university hospital and Center of the digestive system. It was done on 100 patients who underwent Esophago-gastro-duodenoscopy. A total of 100 duodenal aspirate samples were collected from patients were subjected to Esophagogastroduodenoscopy for diagnostic or therapeutic reason. All cases were reviewed as regard age, sex. Cases with parasitic infestations were characterized regarding the mentioned variables. Results: 60 % of duodenal aspirate samples were positive. Monoparasitized patients constituted 38% (38/100) of patients while 22% were polyparasitized. There were 44 patients (44%) of Cryptosporidium infection, 21 patients (21%) of Blastocystis hominis infection, 11 patients (11%) of Cyclospora infection, 8 patients (8%) of Giardia lamblia infection. Conclusion: We concluded that the duodenal aspirate samples obtained during gastrointestinal endoscopic procedures helped in diagnosing the parasites.

Deteksi Protozoa Usus Oportunistik pada Penderita Diare Anak di Puskesmas Rawat Inap Pekanbaru

Diarrhea is still a public health problem, especially in developing countries. Diarrhea causes morbidity and highmortality in children. Diarrhea can be caused by viruses, bacteria, parasites and food poisoning. One of the parasitethat can cause diarrhea is intestinal protozoa. Lately, attention to intestinal opportunistic protozoan infections isincreasing. Opportunistic intestinal protozoa infection is an infection by intestinal protozoa that had not consideredimportant and now can cause disease in humans. Cryptosporidium sp, Cyclospora cayetanensis, Isospora belii andBlastocystis hominis are opportunistic intestinal protozoa. The clinical manifestations of the infection depends on theimmune status of patients, ranging from asymptomatic in immunocompetent individuals to chronic diarrhea not curedand fatal in patients imunokompromis. This study aims to detect opportunistic intestinal protozoa in children withdiarrhea patients in health centers Inpatient Pekanbaru used modified acid fast stain procedure. A total of 76 samplestested positive obtained 22.3% of opportunistic intestinal protozoa found that 9.2% were infected with Cryptosporidiumsp, Cyclospora infection were 2.6% and Blastocystis hominis 10.5%, while Isospora not found.

Coccidian parasitic infection in HIV positive patients attending Tertiary care Hospital in Nepal

Background: Enteric opportunistic parasites are the leading cause of gastrointestinal tract infection in patients with HIV/AIDS. This study was carried out to establish the occurrence of intestinal coccidian parasitic infection among the HIV positive patients in Eastern Nepal. Materials and method: This was a hospital based study carried out in Microbiology laboratory, BPKIHS, Dharan, Nepal over a period of one year (May 2013 to April 2014). All HIV positive patients with CD4+ count ?200cells/l were included. Total 50 HIV positive patients participated in the study over one year period. Stool sample was collected after taking an informed written consent from the patient. Isolation and identification was done as per standard Microbiological procedure. Result: . The overall prevalence of intestinal parasitic infection in present study was 38%. Among the parasites, coccidian parasites comprised of 57.89% of total parasitosis, among 20% (n= 10) cases. Out of total coccidian parasites identified Cryptosporidium parvum comprised 72.7%, Cyclospora cayetanensis 18.2% and Isospora belli 9.1%. One patient had mixed Cryptosporidial and Cyclospora infection. Conclusion Coccidian parasitic infections are common in HIV positive patients at lower CD4+ count in Eastern part of Nepal.

Discovery Recovery Methods and Detection of food borne parasites

In 2013, more than 640 individuals acquired Cyclospora infection in the US. Illness was associated with consumption of imported salad mixes and cilantro that were commercially processed and rinsed. To date, there is no protocol that would allow testing of large volumes of water to detect small number of parasites in produce wash‐waters. Cryptosporidium parvum and Cyclospora cayetanensis are protozoan parasites causing gastrointestinal illness in humans and animals both immunocompetent and immunocompromised hosts. Cryptosporidium parvum are spherical, 4–5μm in size, it can be acquired when ingesting foods and drinking, or accidentally ingesting, water contaminated with feces containing Cryptosporidium oocysts. The illnesses are characterized by acute diarrhea, stomach cramps, nausea, vomiting, and weight loss. Cyclospora cayetanensis are spherical as well, it is 8–10μm in size, it can also be acquired by person‐to‐person transmission and when in contact with infected animals; it is also spread via the fecal‐oral route (the host must ingest something that had been contaminated with feces that contain infectious oocysts). For oocysts to be termed infectious, the oocyst has to be sporulated (produce or form spores). The related disease Cyclosporiasis is acquired by ingestion of water or foods contaminated with human feces containing Cyclospora oocysts. Water samples were collected from a wash site in the southern area of Georgia every other day. The objective of this study was to compare two methods for oocyst recovery and detection from carrot wash‐water. The carrots were grated and washed with the water sample. The carrot wash‐water was spiked with ten and fifty oocysts of Cryptosporidium and Cyclospora. Two types of produce wash solutions fresh water and chlorinated water used by the fresh produce industry were evaluated ten liters of wash water were flocculated or filtered and then concentrated by centrifuging. Cryptosporidium oocysts from the concentrated water sample was treated with immunomagnetic separation (IMS) and detected by immunofluorescence assay (IFA). Cyclospora oocysts were concentrated by discontinuous sucrose gradients and examined by Nomarski microscopy. All samples were further examined by nested Polymerase Chain Reaction (PCR) specific for each parasite. Though both methods effectively recovered parasites, our trial also suggests that filtration and flocculation does not completely remove Cryptosporidium and Cyclospora oocysts in the wash water. In conclusion, these methods can significantly contribute to environmental testing during outbreak investigations and surveillance studies.Support or Funding InformationNSF #1067896

Simultaneous Molecular Detection of Cryptosporidium and Cyclospora from Raw Vegetables in Korea.

Cryptosporidium and Cyclospora are well-known coccidian protozoa that can cause waterborne and foodborne diarrheal illnesses. There have been a few reports regarding contamination in different vegetables with Cryptosporidium, but no data are available regarding the sources of Cyclospora infections in Korea. In the present study, we collected 6 kinds of vegetables (perilla leaves, winter-grown cabbages, chives, sprouts, blueberries, and cherry tomatoes) from July 2014 to June 2015, and investigated contamination by these 2 protozoa using multiplex quantitative real-time PCR. Among 404 vegetables, Cryptosporidium and Cyclospora were detected in 31 (7.7%) and 5 (1.2%) samples, respectively. In addition, Cryptosporidium was isolated from all 6 kinds of vegetables, whereas Cyclospora was detected in 4 kinds of vegetables (except perilla leaves and chives). Cryptosporidium (17.8%) and Cyclospora (2.9%) had the highest detection rates in chives and winter-grown cabbages, respectively. Cryptosporidium was detected all year long; however, Cyclospora was detected only from October to January. In 2 samples (sprout and blueberry), both Cryptosporidium and Cyclospora were detected. Further investigations using TaqI restriction enzyme fragmentation and nested PCR confirmed Cryptosporidium parvum and Cyclospora cayetanensis, respectively. In conclusion, we detected C. cayetanensis in vegetables for the first time in Korea. This suggests that screening should be employed to prevent these protozoal infections in Korea.

Marked seasonality of Cyclospora cayetanensis infections: ten-year observation of hospital cases, Honduras

BackgroundDocument seasonality occurrence and epidemiologic characteristics of Cyclospora cayetanensis infections during a 10-year period from patients consulting at the University Hospital, Honduras.MethodsRetrospective non interventional hospital-based study analyzed laboratory results from the period 2002 to 2011 of fresh and Ziehl-Nielsen carbolfuchsin stained routine stool samples received for parasitologic examination. Sporadically a sample with numerous oocysts was allowed to sporulate in 2.5 % potassium dichromate confirming the presence of bi-cystic bi-zoic oocysts.ResultsA total of 35,157 fecal samples were examined during a ten-year span, of which a third (28.4 %) was stained by the Ziehl-Neelsen carbolfuchsin method diagnosing a total of 125 (1.3 %) C.cayetanensis infections. A statistically significant apparent seasonality was observed most years during May to August (range p < 0.036–0.001), with 83.3 % of 125 cases occurring in those rainy months. All C. cayetanensis cases came from urban poor neighborhoods; male/female relation was 1:1 except in 2006, when all patients were females (p = 0.05; r2 = 22,448). Forty four point eight percent of the stool samples were diarrheic or liquid and 65.6 % infections were identified in children 10 years old or less. Enteric helminths and protozoa co-infected Cyclospora positive patients in 52 instances.: 8 % Ascaris lumbricoides, 8 % Giardia duodenalis, 23.2 % Blastocystis spp. and less frequently Entamoeba histolytica/E. dispar, Strongyloides stercoralis, and Trichuris trichiura.ConclusionsResults suggest a seasonal pattern for Cyclospora infections diagnosed in a clinical setting during the rainy months in Tegucigalpa and surrounding areas. Community studies should be conducted to support or dispute these observations.

Cyclospora infection linked to travel to Mexico, June to September 2015.

Cyclospora cayetanensis was identified in 176 returned travellers from the Riviera Maya region of Mexico between 1 June and 22 September 2015; 79 in the United Kingdom (UK) and 97 in Canada. UK cases completed a food exposure questionnaire. This increase in reported Cyclospora cases highlights risks of gastrointestinal infections through travelling, limitations in Cyclospora surveillance and the need for improved hygiene in the production of food consumed in holiday resorts.

Molecular characterization of clinical isolates of Cyclospora cayetanensis from patients with diarrhea in India

Purpose:Cyclospora cayetanensis is an intestinal coccidian protozoan that has emerged as an important cause of both epidemic and endemic protracted diarrhea worldwide. Though humans appear to be the only natural hosts; the role of animals as natural reservoir is uncertain but of increasing concern. The present study aimed to study the prevalence of coccidian in different groups such as immunocompromised, clinically apparent immunocompetent and healthy individuals. Also, the study isolates were assessed for heterogeneity among the sequences. Materials and Methods: Stool samples from different groups of patients were collected. The parasite was detected in stool by different diagnostic tools such as light microscopy and nested PCR-restriction fragment length polymorphism using 18S ribosomal RNA as the target gene. Results: The prevalence of C. cayetanensis was 2.4% (19/800) in the present study. The PCR assay amplified Cyclospora cayetanensis DNA in only 89% (17/19) isolates. Further, sequencing revealed no significant difference among the study isolates and the non-primates. Phylogenetic analysis of the study isolates however, formed two clusters. While one cluster showed close evolutionary association with the C. cayetanensis strains, the other cluster showed evolutionary association with the two non-primate species. Conclusion: The methods described here for detection of C. cayetanensis oocysts are simple, efficient, specific, and sensitive and therefore can be effectively applied for laboratory diagnosis and environmental assessment of fresh produce and water sources. Clinicians should include Cyclospora infection in the differential diagnosis of prolonged or relapsing diarrheal illness even in clinically apparent immunocompetent individuals.

Cyclospora infection in a young woman with human immunodeficiency virus in Hong Kong: a case report

BackgroundCyclospora is an uncommon pathogen. The diagnosis of Cyclospora infection can be difficult because of its scarcity in developed countries, intracellular mode of life, small size of the parasite and its inability to take up routine microscopic stains. However, it is endemic in many countries in Asia, Africa, Central and South America. With the increase in travels to these areas, the number of cases is expected to increase. Moreover, it is found to be associated with numerous food-borne outbreaks.Case presentationWe encountered a patient with human immunodeficiency virus presented with 6 months of diarrhoea. The initial investigation was unrevealing. The diagnosis of Cyclospora infection was finally made on the histological sample obtained by colonoscopy. Moreover, the initial therapy with ciprofloxacin was not effective, while trimethoprim/sulfamethoxazole resulted in final cure of the disease.ConclusionTravel and food histories are important for the suspicion of Cyclospora infection. Histological examination is more sensitive in making a diagnosis of Cyclospora infection of the gut than fecal microscopic examination. Trimethoprim/sulfamethoxazole is a more reliable therapy for Cyclospora infection in patients with human immunodeficiency virus.

Molecular characterization of Cyclospora-like organisms from golden snub-nosed monkeys in Qinling Mountain in Shaanxi province, northwestern China.

Cyclospora spp. have been identified as one of the most important intestinal pathogens causing protracted diarrhea in animals and human beings. To determine the Cyclospora species in the non-human primate Rhinopithecus roxellanae, a total of 71 fecal samples from 19 endangered snub-nosed monkeys in Shaanxi province were collected and examined using Sheater’s sugar flotation technique and by sequencing the fragments of 18S rDNA. Only two Cyclospora isolates from 2 golden snub-nosed monkeys (R. roxellanae) were obtained and identified between July 2011 and August of 2012. The sequences of the 18S rDNA for the two Cyclospora isolates were 477 bp, with no nucleotide variation between them. Phylogenetic analysis based on the 18S rDNA sequences revealed that the two Cyclospora isolates were posited into the clade Cyclospora spp. and sistered to C. colobi. These results first showed that Cyclospora infection occurred in R. roxellanae in hot and rainy weather, which would provide useful information for further understanding the molecular epidemiology of Cyclospora spp. and the control of Cyclospora infection in non-human primates as well as in human beings.

Answer to December 2012 Photo Quiz

Answer: Cyclospora cayetanensis. Cyclospora cayetanensis is an intestinal coccidian protozoon that has emerged as a significant human infectious agent worldwide, causing self-limiting gastroenteritis in immunocompetent hosts. Human-to-human spread of the parasite occurs indirectly via the environment through oocysts in contaminated water, food, or soil. The parasite has a cosmopolitan distribution and is endemic in tropical and subtropical areas (3). The parasite is commonly limited to travelers to Latin America, the Indian subcontinent, and Southeast Asia, including China (4); therefore, infection with Cyclospora cayetanensis is known as traveler's diarrhea (5). Cyclospora cayetanensis is an important cause of waterborne and food-borne outbreaks due to imported fruits and vegetables from developing countries. The underreporting of infection with this parasite likely occurs because standard examinations for ova and parasites may not include the identification of Cyclospora oocysts. This oversight is at least partly due to the lack of awareness of this disease among the public and medical workers (1). The following criteria have been established for the diagnosis of cyclosporiasis (by the CDC in 1997): detection of oocysts in stool, intestinal fluid, or small bowel biopsy specimens by microscopic examination; demonstration of oocyst sporulation; and detection by molecular methods (not a routine parasitology screening tool) (2). Cyclospora cayetanensis oocysts are spherical and between 8.0 and 10 μm in diameter, with a 50-nm-thick wall and an outer threadlike coat, which is referred to as a wrinkle by some researchers (see Fig. 1a and b in the photo quiz). Diagnostic tests also include phase-contrast microscopy, modified acid-fast staining with variable staining (from pale to red) (see Fig. 1c and d in the photo quiz), and autofluorescence with UV illumination. Ova and parasite exams typically include only direct and concentrated microscopic exams and trichrome stains without modified acid-fast staining or autofluorescence testing. Multiple stool specimens collected on subsequent days are required because parasites are shed intermittently. Of note, two of our patient's specimens were positive, and one was negative. The treatment for Cyclospora infection is a 7-day course of oral trimethoprim-sulfamethoxazole, which proved to be effective for our patient. Health care providers should evaluate Cyclospora infection in patients presenting long-lasting diarrheal illness and order the appropriate tests for this parasite. (See page 3821 in this issue [doi:10.1128/JCM.00256-12] for photo quiz case presentation)

An outbreak of Cyclospora infection on a cruise ship

In 2010, an outbreak of cyclosporiasis affected passengers and crew on two successive voyages of a cruise ship that departed from and returned to Fremantle, Australia. There were 73 laboratory-confirmed and 241 suspected cases of Cyclospora infection reported in passengers and crew from the combined cruises. A case-control study performed in crew members found that illness was associated with eating items of fresh produce served onboard the ship, but the study was unable conclusively to identify the responsible food(s). It is likely that one or more of the fresh produce items taken onboard at a south-east Asian port during the first cruise was contaminated. If fresh produce supplied to cruise ships is sourced from countries or regions where Cyclospora is endemic, robust standards of food production and hygiene should be applied to the supply chain.