Cyclospora Cayetanensis Infection Research Articles

Cyclospora cayetanensis: A Perspective (2020-2023) with Emphasis on Epidemiology and Detection Methods.

Cyclospora cayetanensis infections are prevalent worldwide, and the parasite has become a major public health and food safety concern. Although important efforts have been dedicated to advance toward preventing and reducing incidences of cyclosporiasis, there are still several knowledge gaps that hamper the implementation of effective measures to prevent the contamination of produce and water with Cyclospora oocysts. Some of these data gaps can be attributed to the fact that access to oocysts is a limiting factor in C. cayetanensis research. There are no animal models or in vivo or in vitro culture systems to propagate the oocysts needed to facilitate C. cayetanensis research. Thus, researchers must rely upon limited supplies of oocysts obtained from naturally infected human patients considerably restricting what can be learnt about this parasite. Despite the limited supply of C. cayetanensis oocysts, several important advances have happened in the past 3 years. Great progress has been made in the Cyclospora field in the areas of molecular characterization of strains and species, generation of genomes, and development of novel detection methods. This comprehensive perspective summarizes research published from 2020 to 2023 and evaluates what we have learnt and identifies those aspects in which further research is needed.

Immunogenic multi-epitope-based vaccine development to combat cyclosporiasis of immunocompromised patients applying computational biology method.

Cyclospora cayetanensis infections, also known as cyclosporiasis, persist to be the prevalent emerging protozoan parasite and an opportunist that causes digestive illness in immunocompromised individuals. In contrast, this causal agent can affect people of all ages, with children and foreigners being the most susceptible populations. For most immunocompetent patients, the disease is self-limiting; in extreme circumstances, this illness can manifest as severe or persistent diarrhea as well as colonize on secondary digestive organs leading to death. According to recent reports, worldwide 3.55% of people are infected by this pathogen, with Asia and Africa being more prevalent. For the treatment, trimethoprim-sulfamethoxazole is the only licensed drug and does not appear to work as well in some patient populations. Therefore, the much more effective strategy to avoid this illness is immunization through the vaccine. This present study uses immunoinformatics for identifying a computational multi-epitope-based peptide vaccine candidate for Cyclospora cayetanensis. Following the review of the literature, a highly efficient, secure, and vaccine complex based on multi-epitopes was designed by utilizing the identified proteins. These selected proteins were then used to predict non-toxic and antigenic HTL-epitopes, B-cell-epitopes, and CTL-epitopes. Ultimately, both a few linkers and an adjuvant were combined to create a vaccine candidate with superior immunological epitopes. Then, to establish the vaccine-TLR complex binding constancy, the TLR receptor and vaccine candidates were placed into the FireDock, PatchDock, and ClusPro servers for molecular docking and iMODS server for molecular-dynamic simulation. Finally, this selected vaccine construct was cloned into Escherichia coli strain-K12; thus, the constructed vaccines against Cyclospora cayetanensiscould improve the host immune response and can be produced experimentally.

Cyclospora cayetanensis Infection in Developed Countries: Potential Endemic Foci?

Cyclospora cayetanensis infection has emerged as a significant public health concern worldwide. Developed countries are generally considered non-endemic for infection. However, sporadic cases and non-travel-related outbreaks of C. cayetanensis infections associated with domestically grown produce are becoming more common in developed countries. Cyclospora cayetanensis has been detected in fresh produce, surface water, wastewater, irrigation water, and soil in these countries, suggesting that the parasite may be more common in areas with advanced sanitation than previously thought and illustrating the potential risk for exposure and indigenous/autochthonous infections. The evidence suggests the possibility of foci of endemicity in developed countries, particularly in communities where sanitary conditions are compromised, and raises transmission issues that require further research to better define the risks for infection, how widespread C. cayetanensis may be in these areas, and to guide interventions against this infection. The main purpose of the present opinion was to evaluate the presence of cyclosporiasis in developed countries, which is a very important and ongoing issue in food safety.

Global Burden of Cyclospora cayetanensis Infection and Associated Risk Factors in People Living with HIV and/or AIDS.

Cyclospora cayetanensis infections remain one of the most common protozoan opportunistic causes of gastrointestinal diseases and diarrhea among people living with HIV and/or AIDS (PLWHA). This study was conducted to provide a summary of the evidence on the global burden of C. cayetanensis infection and associated risk factors among PLWHA. Scopus, PubMed, Science Direct, and EMBASE were searched up to February 2022. All original peer-reviewed original research articles were considered, including descriptive and cross-sectional studies describing C. cayetanensis in PLWHA. Incoherence and heterogeneity between studies were quantified by I index and Cochran’s Q test. Publication and population bias were assessed with funnel plots and Egger’s asymmetry regression test. All statistical analyses were performed using StatsDirect. The pooled prevalence of C. cayetanensis infection among PLWHA was 3.89% (95% CI, 2.62–5.40). The highest prevalence found in South America was 7.87% and the lowest in Asia 2.77%. In addition, the prevalence of C. cayetanensis was higher in PLWHA compared to healthy individuals. There was a relationship between a higher C. cayetanensis prevalence in PLWHA with a CD4 cell count below 200 cells/mL and people with diarrhea. The results show that PLWHA are more vulnerable to C. cayetanensis infection and emphasizes the need to implement the screening and prophylaxis tailored to the local context. Owing to the serious and significant clinical manifestations of the parasite, an early identification of seropositivity is recommended to initiate prophylaxis between PLWHA with a CD4 count ≤200 cells/mL and PLWHA who do not receive antiviral therapy.

Cyclospora cayetanensis infection in humans: biological characteristics, clinical features, epidemiology, detection method and treatment.

Cyclospora cayetanensis, a coccidian parasite that causes protracted and relapsing gastroenteritis, has a short recorded history. At least 54 countries have documented C. cayetanensis infections and 13 of them have recorded cyclosporiasis outbreaks. Cyclospora cayetanensis infections are commonly reported in developing countries with low-socioeconomic levels or in endemic areas, although large outbreaks have also been documented in developed countries. The overall C. cayetanensis prevalence in humans worldwide is 3.55%. Among susceptible populations, the highest prevalence has been documented in immunocompetent individuals with diarrhea. Infections are markedly seasonal, occurring in the rainy season or summer. Cyclospora cayetanensis or Cyclospora-like organisms have also been detected in food, water, soil and some other animals. Detection methods based on oocyst morphology, staining and molecular testing have been developed. Treatment with trimethoprim-sulfamethoxazole (TMP-SMX) effectively cures C. cayetanensis infection, whereas ciprofloxacin is less effective than TMP-SMX, but is suitable for patients who cannot tolerate co-trimoxazole. Here, we review the biological characteristics, clinical features, epidemiology, detection methods and treatment of C. cayetanensis in humans, and assess some risk factors for infection with this pathogen.

MILÁČEK-VITOVEC STAINING METHOD VERSUS CONVENTIONAL AND MOLECULAR ONES FOR DIAGNOSIS OF CYCLOSPORA CAYETANENSIS INFECTION

Stool samples from 150 immunocompromised patients (including 120 Gastrointestinal [GI] symptomatic and 30 GI asymptomatic) suspected to have Cyclospora cayetanensis infection were examined to evaluate the validity of Milacek-Vitovec staining method in comparison with kinyoun stain for the diagnosis of cyclosporiasis. All results were confirmed with nested PCR as a gold standard. Validation parameters included sensitivity, specificity, accuracy index, positive predictive value and negative predictive value. In addition, infection intensity was compared among all positive samples. DNAs of Cyclospora oocysts were detected among 30/120 (25%) of GI symptomatic patients versus 1.7 % of GI asymptomatic (5/30). Milacek-Vitovec stain showed more validity than kinyoun with a sensitivity reached 80% versus 73.4% (28 versus 25 from 35 cases) while the specificities of showed 90.4% (104/115) versus 81.7% (94/115), respectively. Mild infection intensity was detected among 10 patients only three of them (30%) were detected by Milacek-Vitovec stain while only one (10%) was detected by Kinyoun, Moderate infection were identified among 10 patients all of them were diagnosed by Milacek-Vitovec stain and 9 (90%) was detected by Kinyoun stain. Heavy infection was detected among 15 patients all diagnosed with Milacek-Vitovec stain while 14 were detected with kinyoun.

Enteric Opportunistic Infection and the Impact of Antiretroviral Therapy among HIV/AIDS Patients from Tehran, Iran

Opportunistic parasites have been identified as human pathogens, especially in immunodeficient patients. Microsporidian and coccidian infections cause chronic diarrhea as common clinical manifestation in HIV positive patients. In this study, the frequency of opportunistic infections, including microsporidian and coccidian infections, was evaluated in HIV/AIDS patients from Tehran and phylogenic analysis was performed for E. bieneusi isolates from these patients. One hundred and two stool samples were collected from confirmed HIV/AIDS patients, referred to Consult Center of Behavior Diseases, West Health Center, Iran University of Medical Sciences in Tehran, Iran. The samples were transferred to Research Center of Pediatric Infectious Diseases, Institute of Immunology and Infectious Diseases, Iran University of Medical Sciences from Jan 2016 to Dec 2016. After conventional formalin-ether concentration, aniline blue staining method and acid-fast staining technique were used for detection of microsporidian spores and Cyclospora oocysts. DNA was extracted and nested PCR was performed. Two (1.96%) cases were found to be positive for intestinal microsporidia infection using aniline blue staining method and were confirmed as E. bieneusi by nested PCR. One patient was found with Cyclospora cayetanensis infection by acid-fast staining method and PCR. Giardia lamblia and Blastocystis hominis were detected as non-opportunistic parasites in 1/102 (0.98%) and 2/102 (1.96%) of the HIV positive patients, respectively. With respect to the use of antiretroviral therapy (ART) in HIV positive patients, we found a low frequency of infection.

Prevalence and associated risk factors of Cystoisospora belli and Cyclospora cayetanensis infection among Iranian patients with colorectal cancer.

From among intestinal parasites, coccidian intestinal parasites such as Cystoisospora belli (previously known as Isospora belli), and Cyclospora cayetanensis are well-known as opportunist parasites, particularly in patients with cancer. This study assessed the prevalence of C. belli and C. cayetanensis in patients with cancer in Lorestan Province, Southwest of Iran. This cross-sectional descriptive study was conducted on 87 patients with colorectal cancers, referred to the general hospitals of Lorestan from October 2017 to August 2018. A fresh stool specimen was collected from each subject in a sterile labeled container. The collected stool samples were concentrated through sucrose flotation method and then prepared for Ziehl-Neelsen staining for microscopic examination. Demographic and possible risk factors such as age, sex, education, residence, and unwashed vegetable/fruit consumption were collected by an applied questionnaire. Out of the 87 patients with colorectal cancer, eight (9.2%) were found positive for C. belli and C. cayetanensis infections, with five (5.74%) and three (3.44%) patients positive for C. belli and C. cayetanensis infections, respectively. Results also showed that sex and unwashed vegetable/fruit consumption were significantly associated with the prevalence of these parasites (p < 0.01). The findings revealed the considerable prevalence of C. belli and C. cayetanensis in patients with colorectal cancers. It is therefore essential for gastrointestinal specialists to pay special attention to the prevalence of coccidian parasites in patients with colorectal cancer.

Antiprotozoal activity of magnesium oxide (MgO) nanoparticles against Cyclospora cayetanensis oocysts

Outbreaks of Cyclospora cayetanensis infection have been linked to consumption of food and water contaminated by oocysts that can survive both physical and chemical disinfectants. Magnesium oxide (MgO) nanoparticles (NPs) can be potentially used in food as bactericides. In this study, C. cayetanensis pre- and post-sporulated oocysts were exposed to MgO NPs with different doses ranging from 1.25–25 mg/ml. With comparison to control, the antiprotozoal activity of MgO NPs was evaluated by identifying the median effective concentration dose (EC50), lethal concentration dose (LC90), microscopically changes on treated oocysts and rates of sporulation. Among pre- and post-sporulated oocysts, MgO NPs ≥ EC50 was observed after 24 h at concentrations 10 and 12.5 mg/ml, respectively, while ≥ LC90 was observed after 24 h, 48 h and 72 h at concentrations 15, 12.5 and 10 mg/ml, respectively. MgO NPs treated oocysts showed abnormal morphological changes such as an increase in size, wall injury, deposition of vacuolated homogenous particles in the cytoplasm, evacuation of oocyst's contents, and collapse. Sporocysts of treated oocysts were noticed to be peripherally shifted. Sporulation failure of treated oocysts achieved ≥90% after 24 h and 72 h of incubation with 15 and 12.5 mg/ml, respectively, while it was 10.1% among non-treated. All the differences were statistically significant. Our results demonstrated that MgO NPs has a significant anti-Cyclospora effect on both unsporulated and sporulated oocysts, especially considering that it could be biologically synthesized, that way it can be used safely as a preventive agent in food and water disinfectant treatment.

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.

Cyclosporaspp. in Drills, Bioko Island, Equatorial Guinea

<i>Cyclospora</i>spp. in Drills, Bioko Island, Equatorial Guinea

Prevalence and Molecular Characterization ofCyclospora cayetanensis, Henan, China

To determine prevalence of Cyclospora cayetanensis infection in Henan, China, we conducted a study of 11,554 hospital patients. Prevalence was 0.70% (95% confidence interval 0.70% ± 0.15%), with all age groups infected. Most cases were found in the summer. Minor sequence polymorphisms were observed in the 18S rRNA gene of 35 isolates characterized.

Cyclospora cayetanensis: First report of imported and autochthonous infections in Kuwait

The intestinal coccidian parasites Cryptosporidium spp. and Cyclospora cayetanensis have emerged as significant human pathogens worldwide. The reports of Cyclospora cayetanensis infection in the Middle East are sporadic and no case has been reported from Kuwait. Stool specimens were collected from six individuals presenting with watery diarrhoea of varying degree and severity at the District General hospitals, Kuwait. Four patients were male, two were female and their ages ranged from 5 to 64 years. Three cases were seen among the migrant population from the Indian subcontinent who had recently returned to Kuwait and two cases were seen in the local population with no history of travel abroad. The stool smears were stained with modified acid-fast stain and examined under ultraviolet (UV) fluorescence illumination. Cyclospora cayetanensis oocysts with variable staining characteristics were detected by microscopy. Two of the cases were also associated with other enteric pathogens. Clinical suspicion of Cyclospora infection was not recorded for any of the cases. All patients showed remarkable symptomatic and parasitologic improvements upon treatment with trimethoprim/sulfamethoxazole. Cyclospora spp. are important aetiological agents of diarrhoea in the Middle East. An awareness of the parasitic infection and use of appropriate diagnostic modalities are essential to elucidate the clinical and epidemiological significance of the parasitosis in this geographic area.

Prevalence of Cryptosporidium, Cyclospora cayetanensis and Isospora belli infection among diarrheal patients in South India

The emerging protozoan parasites Cryptosporidium, Cyclospora cayetanensis and Isospora belli have altered the etiological spectrum of diarrhea. The progressive decline in CD4 cell count in AIDS patients and lack of active immunity in the face of exposure to contaminated food and water in young children make these groups of persons particularly susceptible to protracted and severe diarrhea caused by the above parasites. Cryptosporidiosis is caused by human as well as several zoonotic species. The present study was undertaken to examine the prevalence of Cryptosporidium species, C. cayetanensis and I .belli among these two susceptible populations in comparison with adult immunocompetent individuals with diarrhea and to identify the Cryptosporidium species prevalent in these populations. A total of 447 children under the age of 5 years, 175 HIV-seropositive adults and 200 HIV seronegative adults with diarrhea attending tertiary care hospitals located in the twin cities of Secunderabad and Hyderabad in South India were included in the study. Single fecal samples were collected. Wet mounts and modified Ziehl Neelsen stained smears made from concentrated fecal specimens were screened microscopically for oocysts of Cryptosporidium, Cyclospora cayetanensis and Isospora belli. DNA extracted from fecal samples positive for Cryptosporidium was subjected to PCR RFLP for species identification. Cryptosporidium was detected in all the three groups, I.e. children (8.7%), HIV-seropositive adults (6.85%), and HIV-seronegative adults (1%). Isospora and Cyclospora were detected only among HIV- seropositive persons at a frequency of 16% and 1% respectively. C. hominis (71.7%) and C. parvum (18.9%) were the only 2 species of Cryptosporidium detected.

Diarrhea due to Cyclospora-like organism in an immunocompetent patient

Cyclospora cayetanensis infection continues to be a major cause of diarrhea particularly in immunosuppressed patients. The emergence of new related parasite pathogens, is an issue of public health concern. We report here a case where a Cyclospora-like organism was the cause of diarrhea in an immunocompetent patient from Venezuela.

Transmission of Cyclospora cayetanensis infection: a review focusing on soil-borne cyclosporiasis

In industrialised regions, cyclosporiasis has been most often linked with either food-borne outbreaks or foreign travel. In endemic areas, risk factors associated with the infection include contaminated water or food, contact with animals, type of sanitation and contact with soil. In a community from Venezuela, a strong association was observed between environmental contact with faecal-contaminated soil and cyclosporiasis, suggesting that contact with soil may be an important mode of transmission. This paper reviews the transmission of cyclosporiasis, focusing on soil-related infection.

Epidemiology of Cyclospora cayetanensis infection in San Carlos Island, Venezuela: strong association between socio-economic status and infection

The epidemiology of Cyclospora cayetanensis is not well understood. Few community-based studies have addressed this issue. A study was conducted to determine the prevalence and risk factors for cyclosporiasis in San Carlos Island, Venezuela. A sample of 515 subjects (mean+/-SD: 21.4+/-17.8 years) was surveyed. For identification of the parasite, stools were examined with modified Ziehl-Neelsen carbolfuchsin staining of formalin-ether concentrates. Infections with Cyclospora (43 of 515, 8.3%) were common. There were differences in prevalence of the parasite among sectors of the community: 30 out of 43 (69.8%) cases of cyclosporiasis clustered in two sectors with extreme poverty. Living in these sectors versus the remainder, living in a hut or small residence versus a concrete or larger house, using an area of backyard rather than a toilet or latrine for defecation, and having contact with soil contaminated with human feces were factors strongly associated with the infection (P<0.01). Contact with soil contaminated with human feces might be an important mode of transmission, and poverty a predisposing factor, for the infection.

Cardiac arrest associated with febrile illness due to U.K. acquired Cyclospora cayetanensis

This report describes a 43 yr old man diagnosed with U.K. acquired cyclospora cayetanensis infection resulting in fever and diarrhoea. In course of the febrile illness, he suffered an out of hospital cardiac arrest. Extensive cardiac investigation including a transthoracic echocardiogram, coronary angiogram, and cardiac electrophysiological studies failed to identify the cause. The possible links between cyclospora infection and cardiac arrest are explored. Fever has been reported as a precipitant for idiopathic ventricular fibrillation in patients with the Brugada syndrome but also rarely in individuals with normal hearts. Clinicians should be aware of a possible link between any febrile illness and potentially fatal ventricular dysrhythmia.

Cyclosporiasis Outbreak, Indonesia

We describe an outbreak of Cyclospora cayetanensis infection among Dutch participants at a scientific meeting in September 2001 in Bogor, Indonesia. Fifty percent of the investigated participants were positive for C. cayetanensis. To our knowledge, this outbreak is the first caused by C. cayetanensis among susceptible persons in a disease-endemic area.

Cyclospora cayetanensis infection: vegetables and water as possible vehicles for its transmission in Lagos, Nigeria

(2003). Cyclospora cayetanensis infection: vegetables and water as possible vehicles for its transmission in Lagos, Nigeria. British Journal of Biomedical Science: Vol. 60, No. 2, pp. 113-114.