Update on the major imported protozoan infections in travelers and migrants.

Globalization has contributed to the emergence of specific parasitic diseases in novel geographical areas, and in these regions, these infections in travelers and immigrants may cause a considerable burden of disease. Timely diagnosis and treatment of protozoan infections to decrease mortality and prevent associated complications are essential. In this respect, the increased availability of specific DNA-detection procedures has improved the diagnosis of many imported parasitic infections. Travelers and immigrants with associated comorbidities or immunosuppression may pose a special challenge regarding management. An updated review of the main protozoan infections in mobile populations (malaria, Chagas disease, leishmaniasis, enteric protozoan infections) is provided, focusing on the changing epidemiology of these diseases, recent developments in diagnosis and management and the possibility of local transmission of imported infections.

Mitochondrial Junction Region as Genotyping Marker for Cyclospora cayetanensis.

Cyclosporiasis is an infection caused by Cyclospora cayetanensis, which is acquired by consumption of contaminated fresh food or water. In the United States, cases of cyclosporiasis are often associated with foodborne outbreaks linked to imported fresh produce or travel to disease-endemic countries. Epidemiologic investigation has been the primary method for linking outbreak cases. A molecular typing marker that can identify genetically related samples would be helpful in tracking outbreaks. We evaluated the mitochondrial junction region as a potential genotyping marker. We tested stool samples from 134 laboratory-confirmed cases in the United States by using PCR and Sanger sequencing. All but 2 samples were successfully typed and divided into 14 sequence types. Typing results were identical among samples within each epidemiologically defined case cluster for 7 of 10 clusters. These findings suggest that this marker can distinguish between distinct case clusters and might be helpful during cyclosporiasis outbreak investigations.

Population-based active surveillance for Cyclospora infection--United States, Foodborne Diseases Active Surveillance Network (FoodNet), 1997-2009.

BACKGROUND: Cyclosporiasis is an enteric disease caused by the parasite Cyclospora cayetanensis. Since the mid-1990 s, the Centers for Disease Control and Prevention has been notified of cases through various reporting and surveillance mechanisms. METHODS: We summarized data regarding laboratory-confirmed cases of Cyclospora infection reported during 1997-2009 via the Foodborne Diseases Active Surveillance Network (FoodNet), which gradually expanded to include 10 sites (Connecticut, Georgia, Maryland, Minnesota, New Mexico, Oregon, Tennessee, and selected counties in California, Colorado, and New York) that represent approximately 15% of the US population. Since 2004, the number of sites has remained constant and data on the international travel history and outbreak status of cases have been collected. RESULTS: A total of 370 cases were reported, 70.3% (260) of which were in residents of Connecticut (134 [36.2%]) and Georgia (126 [34.1%]), which on average during this 13-year period accounted for 29.0% of the total FoodNet population under surveillance. Positive stool specimens were collected in all months of the year, with a peak in June and July (208 cases [56.2%]). Approximately half (48.6%) of the 185 cases reported during 2004-2009 were associated with international travel, known outbreaks, or both. CONCLUSIONS: The reported cases were concentrated in time (spring and summer) and place (2 of 10 sites). The extent to which the geographic concentration reflects higher rates of testing, more sensitive testing methods, or higher exposure/infection rates is unknown. Clinicians should include Cyclospora infection in the differential diagnosis of prolonged or relapsing diarrheal illness and explicitly request stool examinations for this parasite.

[Cyclospora cayetanensis: biology, environmental distribution and transfer]. / Cyclospora cayetanensis: biología, distribución ambiental y transferencia.

Cyclospora cayetanensis is an apicomplexan protozoan that has emerged as an important pathogen causing endemic or epidemic diarrheal disease worldwide. In industrialized countries, the parasite has been recognized as the causative agent of several outbreaks of diarrheal illness mostly associated with produce imported from endemic areas. In developing countries, human cyclosporosis is widely distributed. Infection rates from 0% to 41.6% have been described in the general population. However, the epidemiology, biology, and ecology of C. cayetanensis are not fully understood. The life cycle is not completely characterized, although it appears to require a single human host to be accomplished. The role of animals as natural reservoirs of the parasite remains to be determined. Little information is available concerning the environmental distribution and vehicles of transmission of C. cayetanensis. Contaminated water, foods or soil can be vehicles of spread of the parasite. The significant uncertainties that remain in the knowledge of C. cayetanensis highlight the need for continuing research in several areas, including its basic biology and environmental distribution.

Cyclospora papionis, Cryptosporidium hominis, and human-pathogenic Enterocytozoon bieneusi in captive baboons in Kenya.

Cyclospora papionis, Cryptosporidium hominis, and Enterocytozoon bieneusi were detected in 42 (17.9%), 6 (2.6%), and 29 (12.3%) of 235 newly captured baboons in Kenya, respectively. Most C. hominis subtypes and E. bieneusi genotypes found have been detected in humans in the area, suggesting that cross-species transmission of cryptosporidiosis and microsporidiosis is possible.

[Notable imported infectious diseases].

Japanese doctors are somewhat unfamiliar with imported infectious diseases, however, the following imported infectious diseases are notable: cholera, which is currently endemic in Haiti and which there is a possibility of it being imported to Japan from endemic areas; typhoid fever and paratyphoid fever, whose causative organisms showing low sensitivity to fluoroquinolones have become predominant; rabies, which exhibits a high mortality; avian influenza H5N1, which has the possibility of changing into a new type of human influenza; chikungunya fever, in which the number of Japanese patients is increasing; and cyclosporiasis, which led to a number of food poisonings in the USA and Canada, and as a growing number of Japanese travel abroad, the number of infected Japanese patients returning from endemic areas will increase. It is thus important to identify the presence of these diseases on diagnosis.

[An imported Japanese case of cyclosporiasis].

A 42-year-old Japanese woman, who resided in Indonesia suffered from watery diarrhea. As soon as she returned to Japan, she had a medical examination at our hospital. Oocysts of Cyclospora cayetanensis were isolated from her stool on the 14th day. Treatment with 1.6g/day sulfamethoxazole/trimethoprim combination for 1 week was effective. Cyclosporiasis is a of newly-emerging infection and causes group infection or traveler's diarrhea. Cyclosporiasis should be suspected in patients with diarrhea who have returned from the endemic areas to Japan.

Epidemiology of Cyclospora cayetanensis: A review focusing in endemic areas.

Cyclospora cayetanensis is an intestinal coccidian protozoon that has emerged as an important cause of endemic or epidemic diarrhoeal illness in children and adults worldwide. Humans appear to be the only natural hosts. However, the role of animals as natural reservoirs is uncertain but of increasing concern. Human-to-human spread of the parasite occurs indirectly via the environment through oocysts in contaminated water, food or soil. In endemic areas, risk factors associated with the infection include contaminated water or food, contact with soil or animals, type of sanitation and low socioeconomic status. Infections linked to soil contact provide reasons to believe that this route of spread may be more common than realised in disadvantaged community settings. C. cayetanensis is an important cause of traveller's diarrhoea and numerous large foodborne outbreaks associated with the globalisation of the food supply and importation of fruits and vegetables from developing countries have occurred. Waterborne outbreaks have also been reported. Implementation of measures to prevent or control the spread of Cyclospora oocysts in the environment is critical. In endemic areas, the most important steps to prevent infection are improving environmental sanitation and health education. Significant gaps remain in our understanding of the epidemiology of human cyclosporiasis that highlight the need for continued research in several aspects of C. cayetanensis.

[Importance of contact with soil in the transmission of cyclosporosis]. / Importancia del contacto con la tierra en la transmisión de la ciclosporosis.

Cyclospora cayetanensis is an emergent pathogen that causes endemic and epidemic diarrhea worldwide. The epidemiology of the infection is not well known. Transmission of the parasite occurs through an environmental vehicle. In industrialized countries, cyclosporosis has been most often associated with either food-borne outbreaks or traveller's diarrhea. In developing countries, infection has been linked with contaminated water or food, contact with animals or soils, and variables related with socioeconomic status. In a Venezuelan community, a strong correlation between environments conducive to fecal contamination and infection was observed, suggesting that direct contact with contaminated soil may be an important route of transmission in areas with substandard housing developments, and poverty a predisposing factor for cyclosporosis.

[Cyclospora cayetanensis outbreak in travelers to Cuba]. / Brote de Cyclospora cayetanensis en viajeros a Cuba.

Initially described in travelers, outbreaks of cyclosporiasis were soon linked to imported food products. An outbreak of cyclosporiasis in Spanish travelers is described. After identification of Cyclospora cayetanensis in stool analyses, a specific questionnaire was completed. Pyrosis was described in 57% of cases (4/7). Peptic symptoms can be a useful clue to indicate the diagnosis of cyclosporiasis in patients with travelers' diarrhea.

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.

Role of water in the transmission of cyclosporiarsis in Sharkia Governorate, Egypt.

Water samples were collected form five residential areas in El-Ekhewa Village where the human populations use this water for daily activity and for consumption. These water sources were Bahr El-Baker drain, low running irrigation canal, underground water at shallow depth (3-8 m), finished piped water and underground water >35 m deep. The samples were concentrated by flocculation method and the concentrated pellets were examined by ultraviolet (UV) epifluorescence microscopy for Cyclospora oocysts. The densities of water contamination by 8-10 microm oocysts/liter in the five sources were respectively: 2400, 1900, 700, 200 and zero. This indicated that finished water was sewage contaminated. Stool samples from 109 diarrheal patients and 231 non-diarrheal ones from these areas were examined by the acid fast-trichrome stain, Saline Haemo De single slide trichrome stain and by standard bacteriologic techniques. Those with Cyclospora as single pathogen were considered (5.6%) of diarrheal and (2.3%) of the non-diarrheal individuals. The correlation between the density of water contamination and the prevalence of cyclosporiasis among the individuals of each area was significant. No doubt, water was the main vehicle of transmission in the present community. Soil contact and poultry were significant risk factors.

Cyclospora cayetanensis, a food- and waterborne coccidian parasite.

Food- and waterborne coccidia including Cryptosporidium parvum, Cyclospora cayetanensis, Sarcocystis hominis and Sarcocystis suihominis, and Isospora belli are cyst-forming apicomplexan protozoa that cause intracellular infections, predominantly in the epithelial cells of the intestine. They are transmitted by oocysts from person-to-person by the fecal-oral route or via contaminated water or food. The most common symptom of infection is diarrhea, however, asymptomatic infections occur. Infections are associated with intestinal inflammation, with pathological lesions such as villus blunting, and abnormal function such as malabsorption. Mild-to-moderate, self-limiting diarrhea is common in healthy individuals ingesting infective stages of these organisms. However, patients with immune dysfunction can have severe intestinal injury and prolonged diarrhea. Diagnosis in many cases is made by a microscopic examination of the stool, and the use of appropriate staining techniques, but more recently molecular methods for detection are used increasingly. Effective antimicrobial treatment for prolonged infection in immunocompromised patients is available for most of these infections. These gastrointestinal coccidial pathogens have important similarities in epidemiology, disease pathogenesis, clinical manifestations, diagnosis, and treatment. Although there are many other cyst-forming coccidia of public health, veterinary and/or economic importance, discussion in this chapter will be limited to C. cayetanensis, as an important example of the group. Aspects of the biology, epidemiology, diagnosis, disease, treatment and control are considered. This parasite is considered to be an emerging pathogen. From 1990 to 2000, there were 11 foodborne outbreaks of cyclosporosis in North America that affected at least 3600 people. There are many outstanding questions regarding this parasite and under-reporting is common because general diagnostic methods for intestinal parasites are inadequate for detection of Cyclospora.

[Cyclosporidiosis: clinical and diagnostic characteristics of an epidemic outbreak]. / Ciclosporidiosis: características clínicas y diagnósticas de un brote epidémico.

BACKGROUND: Cyclospora cayetanensis, a coccidian parasite, has increasingly been recognized as a cause of gastrointestinal tract illness. We describe a group of patients with this infection. OBJECTIVES: Our aim was to describe the observed clinical course and spectrum of the disease. METHODS: We conducted a prospective study of 101 patients with diarrhea who attended the same wedding reception. RESULTS: Mean incubation period was 8 days; commonly reported symptoms included diarrhea (91%), with 10 or more loose stools in a 24-h period. The illness had a characteristic waxing and waning course and in nearly 72% of patients there occurred symptom recurrence. Other reported symptoms in our patient group included vomiting and fever; 72% of patients had received antibiotics, mainly quinolones, without good response. Watercress was probable vehicle of transmission. CONCLUSIONS: Cyclospora may cause severe diarrhea with a long incubation period and recurring symptoms, which should be considered in evaluation of prolonged gastrointestinal illness. To our knowledge, this is the first outbreak reported in Mexico.

[Cyclospora cayetanensis presence in aquatic surroundings in Hanoi (Vietnam). Environmental study (well water, lakes and rivers)]. / Cyclospora cayetanensis et sa présence en milieu hydrique à Hanoï (Vietnam). Etude dans l'environnement (eaux de forage, lacs et rivières).

Cyclospora cayetanensis is a pathogenic agent originating from the intertropical zone. It causes diarrhoeal diseases in local populations as well as in travellers visiting these zones. In the first part of this work, an epidemiological study on drinking water supply (reservoirs and consumers' taps) was conducted in Hanoi over 12 months; samples were daily collected and have revealed the presence of Cyclospora cayetanensis oocysts during the whole year in tanks and only during monsoon season. Molecular methods were used for species identification. In the second part, we tried to investigate different water sources in Hanoi city in order to detect Cyclospora cayetanensis environmental contamination: groundwaters, surface waters collected in lakes and rivers and also waters from treatment plants. Our results show that none Cyclospora cayetanensis oocyst was found in the groundwaters and in the desinfected finished waters after treatment. In contrast, in rivers and lakes samples, the level of positivity reached about 63.6% with significant differences between the districts regarding the rates of oocysts recovery: only 24% positive specimens in Hoan Kiem district, whilst respectively 80.4%, 78.3% and 65% positive samples in Hai Ba Trung, Dong Da and Ba Dinh districts. The results of this study seem to confirm that environmental water is contaminated by Cyclospora cayetanensis oocysts and points out the importance of water as a significant source of human transmission. It is quite obvious that observation could be probably extended to the other endemic areas.

[Cyclosporiasis: four case reports with a review of the literature].

Four patients infected with Cyclospora cayetanensis who sought medical care at the Tokyo Metropolitan Komagome Hospital are herein presented. All were Japanese males, and their ages ranged from 22 to 50 years of age. One patient, who was HIV-positive with a CD4+ lymphocyte count of 141/microliter, demonstrated no AIDS-defining illness. This patient acquired HIV in some Southeast Asian country/countries through heterosexual contact. This patient presented with watery diarrhea with a frequency of up to 18 times a day for more than two months. The other three cases were not considered to be debilitated hosts. Diarrhea occurring from one to ten times a day continued for 6 to 26 days in all of these three patients. The presumed origin of the infection was considered to be Southeast Asian countries and the season of onset of diarrhea was March to July in all four cases. Treatment with a sulfamethoxazole/trimethoprim compound was performed for both the HIV-infected patient and the other non-debilitated patient. Both symptomatic and parasitologic improvements were quickly observed in these patients. A prospective study was performed using fecal specimens from the diarrheal patients to identify the presence of C. cayetanensis during the period from 1996 to 2001. Protozoa-positive specimens were found in 3 of 410 (0.7%) specimens from patients who had traveled overseas, is one of 148 (0.7%) for HIV-infected (the C. cayetanensis-positive patient also acquired the protozoa in Southeast Asia), and in none of 513 (0%) patients who developed diarrhea in Japan. In summary, C. cayetanensis infection is rare in Japan and most patients infected with this pathogen tend to be overseas travelers and HIV-infected individuals at present.