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An outbreak of cyclosporiasis occurred in attendees of a wedding reception held in Philadelphia, Pennsylvania, on June 10, 2000. In a retrospective cohort study, 54 (68.4%) of the 79 interviewed guests and members of the wedding party met the case definition. The wedding cake, which had a cream filling that included raspberries, was the food item most strongly associated with illness (multivariate relative risk, 5.9; 95% confidence interval, 3.6 to 10.5). Leftover cake was positive for Cyclospora DNA by polymerase chain reaction analyses. Sequencing of the amplified fragments confirmed that the organism was Cyclospora cayetanensis. The year 2000 was the fifth year since 1995 that outbreaks of cyclosporiasis definitely or probably associated with Guatemalan raspberries have occurred in the spring in North America. Additionally, this is the second documented U.S. outbreak, and the first associated with raspberries, for which Cyclospora has been detected in the epidemiologically implicated food item.

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.

This outbreak is the first foodborne cyclosporiasis outbreak reported from central Europe. The illness was reported in 34 persons who attended luncheons at a German restaurant. The overall attack rate was 85% (34/40). The only foods associated with significant disease risk were two salad side dishes prepared from lettuce imported from southern Europe and spiced with fresh green leafy herbs (p=0.0025).

To the Editor: More than a decade has passed since major outbreaks of Cyclospora cayetanensis infection in the United States and Canada drew attention to this newly emerging infection (1, 2). Awareness of these infections was highlighted again by large outbreaks in the summer of 2013 (3). However, many questions remain unanswered regarding this organism, including aspects of its life cycle, geographic distribution, and range of related species. In 1999, three new distinct Cyclospora species noted for their close similarity with C. cayetanensis from humans were isolated from monkeys in Ethiopia (4). A survey of primates in Kenya increased awareness of the extended distribution of these 3 species in eastern Africa and provided confirmation of their marked host specificity, even where the ranges of host species overlapped (5). Most recently, C. colobi–like organisms were identified in snub-nosed golden colobus monkeys in northwestern China (6). We report the characterization of Cyclospora spp. recovered from drills (Mandrillus leucophaeus poensis) on Bioko Island, Equatorial Guinea. During January–February 2011 and 2012, fecal samples from free-ranging animals were collected and placed in 10% formalin (2011) or potassium dichromate (2012). Because samples were collected opportunistically from unidentified animals of undetermined age and sex, whether any samples were collected from the same animals in either year was not known. Fecal samples were concentrated by using the formyl ethyl acetate method, and sediment was examined by using fluorescent microscopy to detect oocysts (4). Three (9%) of 26 samples from 2011 and 8 (31%) of 25 samples from 2012 were positive for Cyclospora oocysts that were spherical, measured 8–10 µm in diameter, and showed autofluorescence. The oocysts collected in potassium dichromate had sporulated by the time of examination, which facilitated and confirmed identification as Cyclospora spp. Representative samples from 4 animals in the second collection were submitted for molecular analysis. The entire 18S rRNA gene (1,796 bp) was obtained from 2 DNA fragments amplified by PCR from DNA extracted from 3 fecal specimens by using procedures and primers for genetic analysis of coccidian parasites (4,7,8). Six distinct full-length 18S rRNA sequences were obtained and compared with sequences in GenBank. Although our sequences showed high similarity with 18S rRNA genes for all Cyclospora species, the sequences were most similar to the C. papionis 18S rRNA gene (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"AF111187","term_id":"4406389","term_text":"AF111187"}}AF111187), even though 3 T→C transitions at nucleotides positions 680, 1054, and 1694 were observed. Analyses of these 6 sequences showed intravariation caused mainly by T→C and A→G transitions. Further studies on different species should be performed to verify whether this is a common feature in Cyclospora spp. 18S rRNA genes. This report extends our knowledge of the range of Cyclospora spp. in monkeys to include western Africa and their host range to include an additional distinct primate species. Results of molecular analysis indicate that this Cyclospora sp. isolate from drills on Bioko Island is most similar to C. papionis from baboons in eastern Africa, an observation that is unexpected and somewhat difficult to explain. Previous studies have suggested that different primate hosts harbor distinctly different Cyclospora species (4–6). Baboons are not found on Bioko Island or in mainland Equatorial Guinea near Bioko Island and are allopatric with drills on the mainland. In addition, drills on Bioko Island have been separated from contact with drills on the mainland for 10,000–12,000 years (9), further isolating the ecology of this host–parasite relationship and confusing how C. papionis was established in drills on Bioko Island. Drills are now considered to have closer phylogenetic affinity with mangabeys (Cercocebus spp.) than with baboons (10), although the phylogeny of these primates is not completely resolved. This finding further confuses an explanation of why the parasite isolated from drills would be similar to that recovered from baboons. It could be speculated that C. papionis arrived on Bioko Island from the mainland through some third host, such as collared (red-capped) mangabeys (C. torquatus), which has close phylogenetic relationships and overlapping ranges with drills and baboons. Any such explanation would mean that Cyclospora spp. infected drills before Bioko Island and the mainland separated. Another possibility is that Cyclospora spp. exhibit host–niche specificity. Colobus monkeys, the host for C. colobi, are arboreal folivores, many of which consume relatively difficult-to-digest foods and have large specialized guts. Vervets, hosts for C. cercopitheci, are also arboreal, but have a frugivorous–insectivorous diet and consume little leaf matter. Baboons and drills, hosts for C. papionis, are predominantly terrestrial and have generalist–omnivorous diets and unspecialized guts. These different ecologic and physiologic differences among the 3 species may affect the observed Cyclospora spp. host specificity. Observations in the present study extend our knowledge of the geographic and host range for cyclosporiasis. However, these observations leave several unanswered questions about our understanding of the parasite in nonhuman primates; the evolutionary relationship between human C. cayetanensis and these closely related species in monkeys; what additional monkey host species, especially on Bioko Island, may harbor Cyclospora spp.; and what other as yet unrecognized species of Cyclospora may be infecting primates.

To the Editor: Protozoan pathogens, including Entamoeba histolytica, Giardia, Cryptosporidium, Cyclospora, Cystoisospora, and microsporidia such as Enterocytozoon bieneusi, are well-known agents of diarrhea and a major public health problem in developing countries. Infection with Cyclospora cayetanensis and E. bieneusi can occur in immunocompromised and immunocompetent persons. Severe diarrhea and weight loss along with anorexia, nausea, and low-grade fever occur in immunocompromised persons, particularly those with HIV/AIDS and transplant recipients who are taking immunosuppressive drugs (1,2). However, transient diarrhea occurs in immunocompetent persons, notably in travelers returning from countries with poor hygienic standards (1–3). We report on a kidney transplant recipient who had uncontrollable diarrhea and weight loss in whom C. cayetanensis and E. bieneusi were detected in biopsy specimens; the diarrhea resolved after treatment with drugs that act specifically on these 2 parasites. The patient was a 55-year-old man from the Dominican Republic living in New York, NY, USA; he had a history of long-term diabetes, coronary disease, and alcoholism. He had undergone a cadaveric renal transplant 14 months earlier and had an uneventful posttransplant course. After returning from visiting family in the Dominican Republic, he sought treatment for acute, profuse watery diarrhea in early November, 2009. He had >10 watery bowel movements daily that were associated with a 20-lb weight loss. His symptoms persisted for 2 months, and he required 2 hospitalizations for the diarrhea. Results of 4 repeat fecal specimen tests (routine diagnostic microscopy and culture) were negative for parasites. Colonoscopy findings were normal; because of evidence of leukocytes in the feces and elevated fecal fat level, however, he received empirically prescribed metronidazole. Because his diarrhea and weight loss persisted, an upper endoscopy was performed, which revealed the presence of microsporidia. He then received albendazole for 3 weeks without substantial benefit. The biopsy specimens were sent to the Centers for Disease Control and Prevention (Atlanta, GA, USA) for further analysis. Biopsy slides were stained with hematoxylin and eosin and with Gram chromotrope (4) and examined by microscopy. The Gram chromotrope–stained slide revealed oval spores, pinkish-red in color, measuring ≈1 µm (5). These spores were supra nuclear in position and were consistent with E. bieneusi (Figure, panel A). The tissue sections were scraped from the slides, DNA was extracted, and conventional PCR was performed by using E. bieneusi–specific primers as described (5); the sizes of the amplified product in the tissue DNA specimen and in the E. bieneusi control specimen were identical (Figure, panel B), confirming the presence of E. bieneusi. On further microscopic examination of the Gram chromotrope and the hematoxylin and eosin–stained slides, oval bodies (8–10 µm) were seen. A few of these oval bodies exhibited 4 spindle-shaped structures which were identified provisionally as merozoites of a coccidian parasite (Figure, panel C). Others had morula-like internal structure (Figure, panel D). We hypothesized that the coccidian parasite could either be C. cayetanensis or Cystoisospora hominis. Because the parasites, in various stages, were just beneath the surface of the epithelium, rather than deep within the epithelium, we believed this organism to be a Cyclospora sp. rather than a Cystoisospora sp. We searched the serum bank of the Division of Parasitic Diseases, Centers for Disease Control and Prevention, and identified a serum sample from a person with a case of C. cayetanensis cyclosporiasis. An indirect immunofluorescence test was performed by using this serum on a deparaffinized section of the tissue biopsy specimen. Different stages of the coccidian organism were labeled brightly and produced apple-green fluorescence against a red counterstain (Eriochrome Black T), indicating that the parasite could possibly be a Cyclospora sp. (Figure, panels E, F). We considered that the Cyclospora-positive serum sample obtained from this particular patient may not be species-specific, since he might have also been infected with Cystoisospora. Therefore, we performed a real-time PCR assay that can distinguish C. cayetanensis from other coccidian parasites to identify the parasite definitively (3). DNA recovered from tissue in paraffin sections was successfully amplified and detected with this assay (data not shown), confirming the presence of C. cayetanensis. Figure Tissue specimens from a kidney transplant recipient with concurrent parasitic infections after traveling to the Dominican Republic. A) Tissue section stained with Gram chromotrope. Note the apical location of a cluster of Enterocytozoon bieneusi spores ... The patient’s illness was treated with albendazole for E. bieneusi infection and with trimethoprim and sulfamethoxazole for C. cayetanensis infection. The patient’s diarrhea subsided after 1 week, and several subsequent fecal samples were negative for microsporidia spores and Cyclospora oocysts. His immunosuppressive medications were reduced, and he remained diarrhea-free for the following 3-year period of April 2010 to April 2013.