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The antennal responses of codling moth females, Cydia pomonella, to volatiles from apple branches with green fruits were recorded by electroantennography coupled to gas chromatography. The antennae strongly responded to 4,8-dimethyl-1,3(E),7-nonatriene, linalool, beta-caryophyllene, (E)-beta-farnesene, germacrene D, (Z,E)-alpha-farnesene, (E,E)-alpha-farnesene and methyl salicylate. These compounds were all present in volatile collections on Porapak Q from both living and cut branches. Analysis by the solid phase microextraction technique (SPME) showed that the emission of some electrophysiologically active compounds increased after branches had been cut, especially 4,8-dimethyl-1,3(E),7-nonatriene, linalool and (E,E)-alpha-farnesene. The identification of apple volatiles eliciting antennal responses is the first step towards the identification of compounds mediating host-finding and oviposition in codling moth females.

A range of infestation levels of the whitefly Bemisia argentifolii Bellows & Perring were established across experimental field plots of cantaloupe by varying insecticide treatments to evaluate the relationships between whitefly density and crop yield and quality. High levels of whitefly adults and immatures were associated with significant reductions in fruit yield, a decrease in fruit size, and an increase in the percentage of fruits with sooty mold. Yield loss rates (kg/ha/adult or nymph) decreased in a nonlinear fashion with increasing whitefly numbers. Estimated economic injury levels varied as a function of whitefly density, whitefly stage, control cost, crop cultivar, and crop season. Estimates of economic injury levels for one ($31.2/ha), five ($156/ha), and 10 ($312/ha) insecticide treatments ranged from 0.02 to 0.39, from 0.12 to 1.96, and from 0.24 to 3.92 adults/leaf, and from 0.20 to 5.43, from 0.98 to 27.17, and from 1.97 to 54.35 nymphs/6.45 cm2, respectively.

Short-term effects on consumption and oviposition rates of four strains of Neoseiulus californicus (McGregor) after a diet shift were evaluated. The new feeding conditions experienced by the predators were six fixed densities of eggs or protonymphs of Tetranychus urticae Koch placed on excised strawberry leaflet discs and maintained under laboratory conditions (25 +/- 1 degrees C, 75-85% RH, 16L: 8D). The observations were made on the first and the fifth day of the experiment. The phytoseiids came from three long-term mass-reared strains fed on T. urticae, Dermatophagoidesfarinae Hughes, or Quercus spp. pollen, respectively. The fourth strain was collected directly in a strawberry field. Time since diet transfer can be added to the factors (i.e. feeding history and prey density) already known to affect the functional and numerical responses of N. californicus, both when it feeds on prey eggs and protonymphs. If consumption rates were averaged over all strains and densities, 9.04 and 11.41 eggs, and 6.97 and 6.48 protonymphs were consumed on the first and the fifth day, respectively. If the same was done for oviposition rates, predators feeding on eggs produced 1.46 and 2.36 eggs/female/day, whereas predators feeding on protonymphs produced 1.35 and 2.29 eggs/female/day. Time had the greatest impact on the functional response of the strain that had previously fed on tetranychids, while an effect of time on the numerical response was detectable in all strains.

The effect of residues of esfenvalerate on oviposition of the resistant strain of the predatory mite Typhlodromus pyri and its main prey, European red mite Panonychus ulmi and two-spotted spider mite Tetranychus urticae, were investigated. T. pyri showed a significant linear reduction in oviposition after 24 h in the presence of increasing levels of esfenvalerate residue applied at the field rate. Furthermore, when given a choice, T. pyri preferred to lay eggs on residue-free surfaces. Of the two prey species, only P. ulmi showed significant avoidance of increasing levels of residues of the field rate concentration of esfenvalerate, as measured by runoff mortality, however both P. ulmi and T urticae, when given a choice, showed a preference for esfenvalerate-free surfaces. As with the predatory mite T. pyri, both prey species showed a significant linear reduction of oviposition with increasing esfenvalerate residues and a preference to lay eggs on esfenvalerate-free surfaces. Esfenvalerate residues as high as 15X field rate were not repellent to pyrethroid-resistant T. pyri. The possible effects of these sublethal effects on predator-prey dynamics and implications for integrated mite control programmes in apple orchards are discussed.

The Musa cultivars, Dwarf Cavendish, Yangambi Km5 and Kunnan, exhibit considerable differences in resistance to Radopholus similis. Infection resulted in significant increases in condensed tannins and flavan-3,4-diols in roots (P < 0.001). The highly resistant cultivar Kunnan had the highest levels of condensed tannins before and after infection. The preinfection levels were similar to the postinfection levels of the two other cultivars. Tannins had mostly procyanidin character, but Kunnan also contained propelargonidins; these compounds may be involved in the resistance mechanism. It is suggested that the butanol/HCl assay be used as a rapid test in screening for resistance to R. similis.

Cyclospora cayetanensis, a coccidian parasite that causes protracted, relapsing gastroenteritis, has a short recorded history. In retrospect, the first 3 documented human cases of Cyclospora infection were diagnosed in 1977 and 1978. However, not much was published about the organism until the 1990s. One of the surprises has been the fact that a parasite that likely requires days to weeks outside the host to become infectious has repeatedly caused foodborne outbreaks, including large multistate outbreaks in the United States and Canada. In this review, I discuss what has been learned about this enigmatic parasite since its discovery and what some of the remaining questions are. My focus is the foodborne and waterborne outbreaks of cyclosporiasis that were documented from 1990 through 1999. The occurrence of the outbreaks highlights the need for health care personnel to consider that seemingly isolated cases of infection could be part of widespread outbreaks and should be reported to public health officials. Health care personnel should also be aware that stool specimens examined for ova and parasites usually are not examined for Cyclospora unless such testing is specifically requested and that Cyclospora infection is treatable with trimethoprim-sulfamethoxazole.

Published techniques for recovering parasites from fruit and vegetables are generally inadequate, with low and variable recovery efficiencies. Herein, we describe an improved method for analyzing fruit and vegetables for Cyclospora oocysts. The technique includes washing procedures, sonication, and separation using lectin-coated paramagnetic beads. Identification is by microscopy (differential interference contrast and fluorescence). Oocyst recovery efficiencies from mushrooms, lettuce, and raspberries were approximately 12%. Recovery efficiencies from bean sprouts were approximately 4%. Although no significant difference in recovery efficiency could be detected between samples processed using the lectin-coated beads and samples processed without this procedure, distinct advantages were apparent when the lectin-coated beads were used. A considerably smaller, cleaner final volume remained for microscopy, which increases the sensitivity of the technique and reduces operator time.

The incidence of foodborne disease outbreaks caused by contaminated low-pH fruit juices is increasing. With recent mandatory pasteurization of apple juice and the industry's concerns of food safety, fruit juice processors are showing more interest in alternative nonthermal technologies that can kill >99.99% of microbial pathogens present in foods. The association of the coccidian protozoan, Cryptosporidium, with diarrheal disease outbreaks from contaminated tap water and fruit juice raises a safety concern in the food and beverage industries. The objective of this study was to evaluate the effects of high hydrostatic pressure (HHP) on C. parvum oocysts. Oocysts were suspended in apple and orange juice and HHP treated at 5.5 x 10(8) Pa (80,000 psi) for 0, 30, 45, 60, 90, and 120 s. Oocyst viability was assessed by excystation using bile salts and trypsin while the cell culture foci detection method was used to assess infectivity. Results indicated that HHP inactivated C. parvum oocysts by at least 3.4 log10 after 30 s of treatment. No infectivity was detected in samples exposed to > or =60 s of HHP and >99.995% inactivation was observed. This study demonstrated that HHP efficiently rendered the oocysts nonviable and noninfectious after treatment at 5.5 x 10(8) Pa.

Published techniques for recovering parasites from fruit and vegetables are generally inadequate, with low and variable recovery efficiencies. Here we describe an improved methodology for analyzing fruit and vegetables for Giardia cysts, Cryptosporidium oocysts, and Ascaris eggs. The method includes washing procedures, sonication, and, for Giardia and Cryptosporidium, immunomagnetic separation. Identification is by immunofluorescence (Giardia and Cryptosporidium) or brightfield microscopy (Ascaris). Recovery efficiencies from lettuce, Chinese leaves, and strawberries were found to be approximately 67% for Giardia, 42% for Cryptosporidium, and 72% for Ascaris. Recovery efficiencies from bean sprouts tended to be more variable and lower. This could be due to material removed with the parasites during the washing procedures, which, in turn, appeared related to the age of the bean sprouts. It is therefore recommended that fruit and vegetables should be as fresh as possible when analyzed for parasites.

Within the last several years, the protozoan parasites Cyclospora cayetanensis, Cryptosporidium parvum, and microsporidia have become recognized as important, rapidly emerging human pathogens in immunocompromised and immunocompetent individuals. Since the early 1990s, many of the reported outbreaks of enteric illness caused by these microorganisms have been attributed to food- and water-borne contamination. Many inherent obstacles affect the success of current surveillance and detection methods used to monitor and control levels of contamination by these pathogens. Unlike methods that incorporate preenrichment for easier and unambiguous identification of bacterial pathogens, similar methods for the detection of parasitic protozoa either are not currently available or cannot be performed in a timely manner. We have developed an extraction-free, filter-based protocol to prepare DNA templates for use in PCR to identify C. cayetanensis and C. parvum oocysts and microsporidia spores. This method requires only minimal preparation to partially purify and concentrate isolates prior to filter application. DNA template preparation is rapid, efficient, and reproducible. As few as 3 to 10 parasites could be detected by PCR from direct application to the filters. In studies, as few 10 to 50 Encephalitozoon intestinalis spores could be detected when seeded in a 100-microliter stool sample and 10 to 30 C. cayetanensis oocysts could be detected per 100 g of fresh raspberries. This protocol can easily be adapted to detect parasites from a wide variety of food, clinical, and environmental samples and can be used in multiplex PCR applications.

Background: The Tetranychus urticae (two-spotted spider mite, TSM) is a spider mite commonly found on fruit trees, herbaceous plants, and greenhouse flowers., Objective: To evaluate the clinical significance of TSM-derived allergens in non-farmers with asthma living around pear orchards, and to assess the allergenic relationship with house dust mite., Methods: Skin prick tests with TSM were performed in 50 asthmatic non-farmers living around pear orchards. The serum TSM-specific IgE was measured in the 16 asthmatics with a positive skin response to TSM. To diagnose TSM-induced asthma, specific bronchial challenges with TSM were performed in the 16 asthmatics. ELISA inhibition tests were performed to assess the allergenic cross-reactivity with house dust mites., Results: Ten of the 16 asthmatics with positive skin responses to TSM showed a significant bronchoconstriction following inhalation of TSM. Eight of the ten TSM-induced asthmatics had high serum TSM-specific IgE and one showed a positive skin response only to TSM. Their asthmatic symptoms were aggravated seasonally, especially in summer and early fall. On ELISA inhibition tests, partial inhibitions with D. pteronyssinus antigens were noted in sera from five asthmatics with positive skin responses to both TSM and D. pteronyssinus, although no inhibition was noted in serum from an asthmatic with a positive skin response only to TSM., Conclusion: Tetranychus urticae may be an important allergen in asthmatic non-farmers living around pear orchards and TSM extracts contain species-specific allergens as well as commonly shared allergens with house dust mite.

Drinking unpasteurized apple juice (or cider) has been associated with cryptosporidiosis, the diarrheal disease caused by the small protozoan parasite, Cryptosporidium parvum. This report compares detection of C. parvum oocysts from apple juice by acid-fast staining (AFS), direct immunofluorescence assay (DIFA), and polymerase chain reaction (PCR), following sample concentration by formalin-ethyl acetate sedimentation or sucrose flotation. Flotation was more efficient than sedimentation in recovering oocysts, and DIFA consistently detected lower numbers of oocysts than AFS. In combination, flotation-AFS could detect 3000 to 10,000 oocysts inoculated into 100 ml of apple juice while flotation-DIFA was able to detect as few as 100 oocysts. The highest sensitivity, 10 to 30 oocysts per 100 ml of apple juice, was achieved by DIFA following immunomagnetic capture (IC) of oocysts from samples concentrated by the flotation method. The detection limit of PCR following flotation or flotation IC was 30 to 100 oocysts; sequence analysis of the amplicon demonstrated that the PCR amplicon was C. parvum-specific.

Cyclospora cayetanensis is a parasitic protozoon that causes prolonged watery diarrhoea. It is endemic in some developing countries, and recent foreign travel is often used as a selection criterion for screening in the United Kingdom (UK). Epidemiological investigations of outbreaks of cyclosporiasis among people in the United States and Canada who had not travelled abroad showed the infection to be foodborne and often associated with foods eaten raw. These included raspberries imported from Guatemala, and pesto (made with basil) and lettuce from other sources. Such foods are also being imported in increasing amounts to the UK, but no outbreaks have been documented, perhaps because none has occurred or because of poor ascertainment. This paper reviews the outbreaks reported from North America, evaluates the risks to the UK population, and suggests how surveillance could be improved.

We investigated the timing of diagnosis, influence of media information on testing for Cyclospora, and the method used to identify cases during eight cyclosporiasis outbreaks in California in spring of 1997. We found that Internet information, media reports, and enhanced laboratory surveillance improved detection of these outbreaks.

The poisoning of Costa Rican banana workers by multinational corporations' excessive use of pesticides is not a local issue; it is embedded in a dominant ideology expressed by the phenomenon of globalization. This ideology seeps into every aspect of our social institutions--economic, political, and legal. The practice of this ideological perspective is evident in the industrialization of global agriculture and the shift from "developmentalism"--liberal welfarism, industrialization, and urbanization--to a dominant, undemocratic, global financial elite with "economism" and a neoliberal political agenda overriding the nation-state polis. A specific effect is to transform the agricultural workers of developing countries, such as Costa Rican banana workers, into politically superfluous flesh-and-blood human beings.

The phylogenetic relationships of all seven known species of Cecidophyopsis mites (Acari: Eriophyidae) with Ribes hosts have been inferred from ribosomal DNA sequences. This analysis found groups of closely related mites. The five gall-forming species, four of which are monophagous and one which has two hosts, were found in two groups. Another group consisted of the two non gall-forming species, one of which has two hosts, while the other is monophagous. The molecular phylogeny of their known Ribes host plants was calculated using the equivalent ribosomal regions as the mites. The structure of the two trees (mites vs hosts) was clearly different, implying that mite speciation did not closely follow speciation events in the plant hosts. Instead, the three groups of Ribes-infesting Cecidophyopsis mites have derived from a common galling ancestor millions of years ago. Each mite group has recently diversified onto different primary hosts. One group of mites has also lost the galling habit. The results have implications for host range changes and the durability of mite-resistance genes in cultivated Ribes.

We introduced a mass-reared pyrethroid-resistant strain of the predatory phytoseiid mite Amblyseius fallacis (Garman) into an Ontario peach orchard in an attempt to control populations of the phytophagous mites Panonychus ulmi Koch and Tetranychus urticae Koch (Acari: Tetranychidae). Releases of 1,000 and 2,000 mites per tree were made, at three different times. The release of 2,000 mites per tree in June and in July resulted in significantly higher phytoseiid densities than was observed on control trees. However, densities of P. ulmi or T. urticae were not significantly affected by any release rate or by timing. The release of 1,000 A. fallacis per tree, or of any density in August, did not significantly increase phytoseiid abundance. In the following year, population dynamics of both phytoseiid and phytophagous mites were not significantly affected by the previous year's release. Amblyseius fallacis can be a useful predator in some fruit orchards. However, further research is necessary into the timing and rate of release, modified spray programmes, and with different crops, in order to clarify the role of this species for biological control in Ontario peach orchards.

Introduction: Prior to 1996, sporadic cases of cyclosporiasis in Canada were most often associated with foreign travel and outbreaks throughout the world were associated with contaminated drinking water. In May 1996, the North York Public Health Department was notified of three laboratory-confirmed cases of cyclosporiasis among persons who attended a luncheon at a religious institution. A ceremonial bath (mikvah) was initially identified as a possible source of exposure to contaminated water., Methods: Guests of a luncheon were interviewed regarding food, beverage and water exposure. The institution kitchen and water sources were inspected and environmental testing was performed., Results: Eating strawberry flan, decorated with rasberries and blueberries, was associated with developing illness (relative risk = 2.13, p = 0.02). There was no evidence that water exposure was associated with illness., Discussion: This event was the index Canadian cluster of a widespread North American outbreak associated with imported Guatemalan raspberries. The local investigation highlights the role of public health departments in multijurisdictional food-borne outbreaks of emerging pathogens.

In 1996 and 1997, cyclosporiasis outbreaks in North America were linked to eating Guatemalan raspberries. We conducted a study in health-care facilities and among raspberry farm workers, as well as a case-control study, to assess risk factors for the disease in Guatemala. From April 6, 1997, to March 19, 1998, 126 (2.3%) of 5, 552 surveillance specimens tested positive for Cyclospora; prevalence peaked in June (6.7%). Infection was most common among children 1.5 to 9 years old and among persons with gastroenteritis. Among 182 raspberry farm workers and family members monitored from April 6 to May 29, six had Cyclospora infection. In the case-control analysis, 62 (91%) of 68 persons with Cyclospora infection reported drinking untreated water in the 2 weeks before illness, compared with 88 (73%) of 120 controls (odds ratio [OR] 3.8, 95% confidence interval [CI] 1.4, 10.8 by univariate analysis). Other risk factors included water source, type of sewage drainage, ownership of chickens or other fowl, and contact with soil (among children younger than 2 years).

Objectives: Until 1995, infection with Cyclospora cayetanenis, a parasite that causes gastroenteritis, was diagnosed in the US primarily in overseas travelers; its modes of transmission were largely unknown. In 1995, 45 cases of cyclosporiasis were diagnosed in Florida residents who had no history of recent foreign travel, but an investigation could not pinpoint a source for the parasite. In 1996, a North American outbreak of cyclosporiasis resulted in more than 1400 cases, 180 of them in Florida. The authors investigated the 1996 Florida outbreak to identify the vehicle of transmission., Methods: The authors conducted a matched case-control study in which each of 86 laboratory-confirmed sporadic cases was matched with up to four controls. They also investigated nine clusters of cases associated with common meals and attempted to trace implicated foods to their countries of origin., Results: In the case control study, eating raspberries was strongly associated with cyclosporiasis (matched odds ratio = 31.9; 95% confidence interval [CI] 7.4, 138.2). In the cluster investigation, raspberries were the only food common to all nine clusters of cases; a summary analysis showed a strong association between consumption of raspberries and confirmed or probable cyclosporiasis (risk ratio = 17.6; 95% CI 1.9, 188.8). Guatemala was the sole country of origin for raspberries served at six of nine events., Conclusions: Guatemalan raspberries were the vehicle for the 1996 Florida cyclosporiasis outbreak. Cyclospora is a foodborne pathogen that may play a growing role in the etiology of enteric disease in this country as food markets become increasingly international.

Background: In the spring of 1996, an outbreak of cyclosporiasis associated with fresh Guatemalan raspberries occurred in the United States and Canada. Another multistate outbreak of cyclosporiasis occurred in North America in the spring of 1997., Objective: To identify the vehicle of the outbreak that occurred in the spring of 1997., Design: Retrospective cohort studies of clusters of cases associated with events (such as banquets) and traceback investigations of sources of implicated produce., Setting: United States and Canada., Patients: Persons who attended events associated with clusters of cases of cyclosporiasis., Measurements: Identification of clinically defined or laboratory-confirmed cases of cyclosporiasis and risk factors for infection., Results: 41 clusters of cases were reported in association with events held from 1 April through 26 May in 13 U.S. states, the District of Columbia, and 1 Canadian province. The clusters comprised 762 cases of cyclosporiasis, 192 (25.2%) of which were laboratory confirmed. In addition, 250 laboratory-confirmed sporadic cases were reported in persons who developed gastrointestinal symptoms from April through 15 June, for a total of 1012 cases. Fresh raspberries were the only food common to all 41 events and were the only type of berry served at 9 events (22.0%). Statistically significant associations between consumption of raspberry-containing items and cyclosporiasis were documented for 15 events (40.5% of 37). For 31 of the 33 events with well-documented traceback data, the raspberries either definitely came from Guatemala (8 events) or could have come from Guatemala (23 events). The mode of contamination of the raspberries remains unknown. The outbreak ended shortly after the exportation of fresh raspberries from Guatemala was voluntarily suspended at the end of May 1997., Conclusions: Similar multistate, multicluster outbreaks of cyclosporiasis associated with consumption of Guatemalan raspberries have occurred in consecutive years. These outbreaks highlight the need for better understanding of the biology and epidemiology of Cyclospora cayetanensis and for stronger prevention and control measures to ensure the safety of produce eaten raw.

Trypanosomatid parasites are fairly common in the latex, phloem, fruit sap, seed albumen, and even in the nectar, of many plant families. They are transmitted to the plants in the saliva of phytophagous hemipterous bugs (Insecta). Morphologically, plant trypanosomatids have no special characteristic, except perhaps a very twisted cell body. Most occur in plants as promastigotes and a few as choanomastigotes. It is still controversial whether or not they are pathogenic in lactiferous plants or fruit, but it is certain that the phloem parasites are pathogenic in coconut palms and coffee bushes. In these plants, they cause lethal diseases responsible for the destruction of many plantations in Central and South America, but fortunately nowhere else in the world. Probably more than one genus of Trypanosomatidae is represented among the plant parasites. The most important is certainly Phytomonas, but Leptomonas, Crithidia and Herpetomonas may also be present. The distinction between them is difficult and only recently have molecular markers become available to help in their identification. At present, Phytomonas can be identified by DNA hybridization with a specific probe (SL3') complementary to a sequence of the mini-exon or spliced leader gene. The development of a polymerase chain reaction coupled to SL3' hybridization has facilitated the detection of Phytomonas in plants. The phylogeny of Phytomonas is still being worked out. For the moment it can only be said that the genus is very close to Herpetomonas.

Raspberries were epidemiologically associated with cyclosporiasis outbreaks during 1996 and 1997. The 18S rRNA genes of Cyclospora cayetanensis and several species of a closely related genus, Eimeria, were sequenced and primers for a nested PCR developed in a previous study. The ability to distinguish amplified products of Cyclospora sp. from those of Eimeria spp. is important for testing food and environmental samples. Therefore, an RFLP analysis of amplified products was used to differentiate Cyclospora cayetanensis from Eimeria spp. PCR inhibitors and the low levels of Cyclospora oocysts present in raspberries make template preparation for PCR challenging. Several approaches for PCR template preparation from raspberry samples were evaluated. Template preparation methods using various washing and concentration steps, oocyst disruption protocols, resin matrix treatment, DNA precipitation, and/or the addition of nonfat dried milk solution to a PCR using modified primers were evaluated first with oocysts of Eimeria tenella then refined with oocysts of C. cayetanensis. Approximately 10 E. tenella oocysts per PCR or approximately 19 C. cayetanensis oocysts per PCR were detected with the optimized template preparation method. The addition of 20 microliters of raspberry wash sediment extract and nonfat dried milk solution did not inhibit the amplification of DNA from as few as 10 E. tenella and 25 C. cayetanensis oocysts in a 100-microliter PCR. The nucleotide sequences of C. cayetanensis and the Eimeria spp. are 94 to 96% similar in the amplified region, but the amplification products from the two genera were distinguished using an RFLP analysis with the restriction enzyme MnlI.

During May-June 1998, the Ontario Ministry of Health and local health departments in Ontario received reports of clusters of cases of cyclosporiasis associated with events held during May. This report describes the preliminary findings of the investigation of a cluster in Toronto, Ontario, and summarizes the findings from investigations of 12 other clusters. These investigations indicated that fresh raspberries imported from Guatemala were linked to the multicluster outbreak.

Background: Cyclospora cayetanensis, a coccidian parasite, has increasingly been recognized as a cause of gastrointestinal tract illness. We describe an outbreak of Cyclospora infection following a wedding reception., Objectives: To investigate and characterize risk factors associated with the outbreak of Cyclospora and to describe the observed clinical course and spectrum of illness., Methods: Retrospective cohort study involving 94 of the 101 guests who attended a wedding reception at a restaurant in Boston, Mass., Results: Fifty-seven respondents met the case definition of infection; 12 of these had laboratory-confirmed Cyclospora. The epidemic curve was consistent with a point source outbreak with a median incubation period of 7 days. Commonly reported symptoms included diarrhea (100%), weight loss (93%), fatigue (91%), and anorexia (90%). The illness had a characteristic waxing and waning course, with 51 persons (89%) reporting recurring symptoms and 35 (61%) reporting illness lasting more than 3 weeks. By univariate analysis, infection was significantly associated (P<.05) with consumption of wine and a dessert containing raspberries, strawberries, blackberries, and blueberries. Only the dessert remained significant by stratified analysis with an adjusted relative risk of 2.1 (95% confidence interval, 1.4-3.2)., Conclusions: Findings from this study support a point source outbreak of the newly identified pathogen C cayetanensis, with berries as the vehicle of transmission. It suggests that Cyclospora may cause severe diarrhea associated with profound anorexia and weight loss, and should be considered in the evaluation of prolonged gastrointestinal tract illness.

We present a patient who developed Guillain-Barré syndrome (GBS) after a Cyclospora-induced diarrheal illness. We raise the possibility that Cyclospora is an infectious trigger for GBS in this patient. An active search for this agent in patients with GBS preceded by diarrheal illness is recommended.

Three flagellates of the family Trypanosomatidae were isolated from mango fruits (Mangifera indica) and from the stems of clover (Trifolium glomeratum) and Amaranth (Amaranthus retroflexus) in southeastern Spain and were adapted to in vitro culture in monophase media. The parasites showed an ultrastructural pattern similar to that of other species of the genus Phytomonas. Mango and clover isolates differed from amaranth isolates in ultrastructural terms. The isolates were characterized by isoenzymatic analysis and by kDNA analysis using five different restriction endonucleases. With eight of the nine enzymatic systems, mango and clover isolates were distinguished from those of amaranth. Nevertheless, with the enzymes malate dehydrogenase and superoxide dismutase, flagellates isolated from clover were differentiated from those isolated from mango. Electrophoretic and restriction-endonuclease analysis of kDNA minicircles showed similar restriction cleavage patterns for the isolates from mango and clover, whereas the patterns of the amaranth isolates differed. The results of the present study confirm that the strains isolated from mango and clover constitute a phylogenetically closely related group of plant trypanosomatids, which is more distantly related to the strain isolated from amaranth. The similarities in the results obtained for isolates from mango and clover foliage, on the one hand, and those obtained from tomato and cherimoya fruits (studied previously), on the other, as well as the geographic proximity of the different plants support the contention that only one strain is involved, albeit one strain that can parasitize different plants. Furthermore, some of the plants appear to act as reservoirs for the parasites. On the other hand, the metabolism studies using [1H]-nuclear magnetic resonance spectroscopy did not reveal that the catabolism of Phytomonas in general follows a pattern common to all the species or isolates. Phytomonas are incapable of completely degrading glucose, excreting a large part of their carbon skeleton into the medium as fermentative metabolites (acetate, ethanol, glycine, glycerol, and succinate).

In 1992, an outbreak of chronic diarrhea occurred among passengers on a cruise ship visiting the Galapagos Islands, Ecuador. Passengers (548) were surveyed, and stool and biopsy specimens from a sample who reported chronic diarrhea were examined. On completed questionnaires, returned by 394 passengers (72%), 58 (15%) reported having chronic diarrhea associated with urgency (84%), weight loss (77%), fatigue (71%), and fecal incontinence (62%). Illness began 11 days (median) after boarding the ship and lasted 7 to >42 months. Macroscopic and histologic abnormalities of the colon were common, but extensive laboratory examination revealed no etiologic agent. No one responded to antimicrobial therapy. Patients were more likely than well passengers to have drunk the ship's unbottled water or ice before onset of illness and to have eaten raw sliced fruits and vegetables washed in unbottled water. Water handling and chlorination on the ship were deficient. Outbreaks of a similar illness, Brainerd diarrhea, have been reported in the United States. Although its etiology remains unknown, Brainerd diarrhea may also occur among travelers.

The effect of 137Cs irradiation on unsporulated and sporulated Toxoplasma gondii oocysts was investigated as a model system for sterilisation of fruit contaminated with other coccidia such as Cyclospora or Cryptosporidium. Unsporulated oocysts irradiated at > or = 0.4 to 0.8 kGy sporulated but were not infective to mice. Sporulated oocysts irradiated at > or = 0.4 kGy were able to excyst, and sporozoites were infective but not capable of inducing a viable infection in mice. Toxoplasma gondii was detected in histologic sections of mice up to 5 days but not at 7 days after feeding oocysts irradiated at 0.5 kGy. Transmission electron microscopy revealed that sporozoites from irradiated oocysts penetrated enterocytes and all cells in the lamina propria except for red blood cells. Sporozoites appeared normal ultrastructurally and formed a typical parasitophorous vacuole containing a well-developed tubulovesicular membrane network. Raspberries inoculated with sporulated T. gondii oocysts were rendered innocuous after irradiation at 0.4 kGy. Results indicate that irradiation at 0.5 kGy is effective in "killing" coccidian oocysts on fruits and vegetables.

Since April 1997, CDC has received reports of outbreaks of cyclosporiasis in the United States and Canada (1,2). As of June 11, there have been 21 clusters of cases of cyclosporiasis reported from eight states (California, Florida, Maryland, Nebraska, Nevada, New York, Rhode Island, and Texas) and one province in Canada (Ontario). These clusters were associated with events (e.g., receptions, banquets, or time-place-related exposures [meals in the same restaurant on the same day]) that occurred during March 19-May 25 and comprise approximately 140 laboratory-confirmed and 370 clinically defined cases of cyclosporiasis. In addition, four laboratory-confirmed and approximately 220 clinically defined cases have been reported among persons who, during March 29-April 5, were on a cruise ship that departed from Florida. Approximately 70 laboratory-confirmed sporadic cases (i.e., cases not associated with events, the cruise, or recent overseas travel) have been reported in the United States and Canada. The most recent laboratory-confirmed sporadic case occurred in a person who had onset of symptoms on June 3.

During April and May 1997, CDC received reports of clusters of cases of cyclosporiasis in the United States. This report describes the preliminary findings of an investigation of an outbreak in New York and summarizes the findings from on-going investigations in other states.

Background: Cyclospora cayetanensis is a parasite that causes gastroenteritis. Until last year most of the documented cases of cyclosporiasis in North America were in overseas travelers. In 1996, a large outbreak of cyclosporiasis occurred in North America. We investigated this outbreak., Methods: Health departments solicited information from clinicians and laboratories on cases of cyclosporiasis, which were then reported to the Centers for Disease Control and Prevention and to Health Canada. We conducted retrospective cohort studies for the cases associated with events (e.g., luncheons) and attempted to identify the sources of the implicated food., Results: A total of 1465 cases of cyclosporiasis were reported by 20 states, the District of Columbia, and 2 provinces. Of these cases, 978 (66.8 percent) were laboratory confirmed and 725 (49.5 percent) were associated with 55 events that were held from May 3 through June 14. Raspberries were definitely served at 50 events and may have been served at 4 events. For 27 of the 41 events for which adequate data were available (65.8 percent), the associations between the consumption of berries (raspberries with or without other berries) and cyclosporiasis were statistically significant (P<0.05). For all 29 events for which there were good data, the raspberries definitely came from Guatemala (21 events, 72.4 percent) or may have come from Guatemala (8 events, 27.6 percent). As few as five Guatemalan farms could have accounted for the 25 events for which the raspberries could be traced to a single exporter per event. The mode of contamination of the raspberries remains unclear., Conclusions: This large outbreak of cyclosporiasis in North America in 1996 was associated with the consumption of Guatemalan raspberries. The outbreak illustrates the need to consider that a local cluster of foodborne illness may be part of a widespread outbreak and to pursue investigations to the source of the implicated vehicle.

Since May 1996, CDC has received reports of clusters and sporadic cases of infection with the parasite Cyclospora cayetanensis that occurred in May and June in the United States and Canada. This report describes preliminary findings of an investigation by the New Jersey Department of Health and Senior Services (NJDHSS) and updates the findings of other ongoing investigations.

Cyclospora cayetanensis (previously termed cyanobacterium-like body) is a recently characterized coccidian parasite; the first known cases of infection in humans were diagnosed in 1977. Before 1996, only three outbreaks of Cyclospora infection had been reported in the United States. This report describes the preliminary findings of an ongoing outbreak investigation by the South Carolina Department of Health and Environmental Control (SCDHEC) and summarizes the findings from investigations in other states.

A seasonal research was carried out in Irapuato, Guanajuato and Zamora, Michoacan, Mexico, the location of the most important producers of strawberries, in order to assess fecal contamination through the finding of protozoan cysts and helminth eggs, specifically of Taenia sp eggs. Three techniques were used: direct observation, flotation and sedimentation. Low numbers of protozoan cysts and only one Ascaris egg were found. What is most interesting is that no Taenia eggs were identified. Results indicate that although strawberries are contaminated with human feces, contamination is minimal.

Plants of Lycopersicon esculentum (grown in greenhouses) and Anona cherimolia cultivated in southeastern Spain were examined for the presence of trypanosomatid flagellates. Kinetoplastid protozoa were found in the fruits but not in the phloem or other plant tissues. Parasites were detected from the onset of fruiting. Isolates were detected from the onset of fruiting. Isolates were adapted to in vitro culturing in monophase media. The form and the structural organization was studied by scanning and transmission electron microscopy. The parasites showed an ultrastructural pattern similar to that of other species of the genus Phytomonas. In tomatoes experimentally inoculated with flagellates cultivated in vitro, we observed that the parasites did not lose their infectious capacity. Three strains of trypanosomatids of the genus Phytomonas, isolated from different species of Euphorbia (E. characias and E. hyssopifolia) and from Cocos nucifera, were compared with our isolates by lectin-agglutination tests. Our isolates were different from the two strains isolated from Euphorbia, but with this technique we could not differentiate our isolates from those of the coconut, nor could we differentiate between the isolates, their ultrastructural similarity together with their similar behavior in the lectin-agglutination test suggesting that these isolates have a common origin.