Detection of Cyclospora cayetanensis on bagged pre-cut salad mixes within their shelf-life and after sell by date by the U.S. food and drug administration validated method.

Recently, outbreaks of Cyclospora cayetanensis in the U.S. were linked to the consumption of a variety of salads containing romaine and/or iceberg lettuce, carrots and/or red cabbage. The Bacteriological Analytical Manual (BAM) Chapter 19b method was validated for the detection of C. cayetanensis in carrots, cabbage and romaine lettuce, but has not been previously evaluated in ready-to-eat (RTE) salad mixes. In addition, the only samples available for traceback investigations are sometimes leftovers in bad conditions. This study evaluated the validated BAM method for detection of C. cayetanensis in two different RTE mixed salads (mix 1: romaine and iceberg lettuces, carrots, and red cabbage and mix 2: romaine and iceberg lettuces, carrots, red cabbage, radish, and pea pods) in good condition and after their sell by date. Individual samples (25 g) were seeded with five and 200 C. cayetanensis oocysts. Unseeded produce was used as negative control. The method included washing of the produce, concentration and extraction of C. cayetanensis DNA and molecular detection of C. cayetanensis 18 S rRNA gene. As few as five oocysts were detected in both fresh and after sell by date mix salads. All unseeded samples were negative, and all samples of both salad types seeded with 200 oocysts were positive. In samples seeded with 200 oocysts, average 18 S rRNA C. cayetanensis CT values were significantly higher in fresh salad mix 1 compared to fresh salad mix 2; CT values were significantly higher in the after sell by date salads compared to their respective fresh mixes (p < 0.05). In conclusion, the BAM method was able to detect as few as five oocysts even in after sell by date RTE mix salads. However, the differences in detection observed, highlight the importance of evaluating the performance of the validated C. cayetanensis detection method in different food matrices and conditions, in advance for future outbreak investigations.

Checking the detail in retail: Occurrence of Cryptosporidium and Giardia on vegetables sold across different counters in Chandigarh, India.

Fresh produce has been recognized as a vehicle of infection for protozoan parasites, particularly Cryptosporidium, and, to a lesser extent, Giardia. For both parasites, outbreaks associated with fresh produce have been documented. Although documented outbreaks tend to be from industrialized countries, contamination of fresh produce with these parasites is a global issue. In developing countries, infections with these parasites are often endemic in the community, and basic infrastructure and hygiene measures may be inadequate, thus the likelihood of contamination of fresh produce with these parasites may be higher. Realization of the importance of this transmission route comes against a backdrop of raw salads and more Western culinary habits gaining a foothold, and fresh produce being encouraged as part of the diet due to their associated health benefits. However, if consumption of uncooked fresh produce is going to increase its market sector in India, it is important that it is safe. In this study, various types of fresh produce obtained from three types of vendors in Chandigarh, a major city in Northern India, were analyzed for contamination with Cryptosporidium oocysts and Giardia cysts using a method that has been previously validated in inter-laboratory spiking experiments. A total of 284 samples of different fresh produce items were analyzed, obtained from the different retailers situated in different societal layers of the city. The overall prevalence of contamination of fresh produce with these parasites was just under 11%, with 6% of the vegetables contaminated with Cryptosporidium oocysts, and 5% with Giardia cysts. Contaminated vegetables included turnip, cabbage, carrot, chili, coriander, cucumber, radishes, and tomatoes. Molecular analyses identified contamination with Cryptosporidium parvum and Giardia duodenalis of Assemblage A and Assemblage D, indicating that contamination from animals may be of relevance. Although the prevalence of contamination is similar to those reported in previous studies, the levels of contamination on some items of fresh produce were relatively high. Although the different socioeconomic areas of Chandigarh from which the samples were obtained was not associated with likelihood of contamination, fresh produce from supermarkets had heavier contamination with Cryptosporidium oocysts than fresh produce purchased through other sales outlets. The results are discussed in relation to the fresh produce chain and sales models in Chandigarh, both in terms of where contamination may occur and the potential importance of fresh produce as a transmission vehicle.

Prevalence of Some Human Enteroparasites in Commonly Consumed Raw Vegetables in Tabuk, Saudi Arabia.

The problem of parasitic contamination of food, especially fresh vegetables, is not limited to personal hygiene during food preparation but is also widely dependent on the source of the food and the handling it undergoes before it gets to the consumer. The objective of the present study was to evaluate parasitic contamination in eight common raw vegetables in Tabuk, Kingdom of Saudi Arabia. A total of 400 samples of raw vegetables obtained from wholesale and retail markets were examined for helminth eggs and larvae and for cysts of different parasites, using standard methods. The prevalence of the parasites was 20.65% in cucumber, 15.76% in cabbage, 14.67% in pea, 14.13% in cress, 13.04% in lettuce, 10.33% in carrot, 8.70% in green onion, and 2.72% in tomato. Statistical analysis showed a significant difference (P < 0.05) for Entamoeba spp. cysts, Ascaris lumbricoides eggs, Entamoeba coli cysts, and unknown isolated parasite cysts. Parasites are common in vegetables that are frequently eaten raw and, for this reason, may pose a health risk for consumers in Tabuk.

Parasitic contamination of fresh vegetables sold at central markets in Khartoum state, Sudan.

BACKGROUND: Fresh vegetables are considered as vital nutrients of a healthy diet as they supply the body with essential supplements. The consumption of raw vegetables is the main way for transmission of intestinal parasitic organisms. This study was aimed at detecting the parasitic contamination in fresh vegetables sold in two central open-aired markets in Khartoum state, Sudan. METHODS: In this prospective cross-sectional study, a total of 260 fresh vegetable samples and 50 water samples used to sprinkle vegetable(s) were collected from two central open-aired markets (namely; Elshaabi and Central markets) during November 2011 to May 2012. The samples were microscopically examined for detection of parasitic life forms using standardized parasitological techniques for protozoans and helminthes worms. RESULTS: Of the 260 fresh vegetable samples, 35 (13.5 %) were microscopically positive for intestinal parasites whereas 7/50 (14 %) of water samples used to sprinkle vegetable(s) were found positives. Remarkably, high level of contamination in fresh vegetable samples was recorded in lettuce (Lactuca sativa) 36.4 % (4/11) while cayenne pepper (Capsicum annuum) and cucumber (Cucumis sativus) were not contaminated. The identified protozoans and helminthes were Entamoeba histolytica/dispar, Entamoeba coli, Giardia lamblia, Ascaris lumbricoides, Strongyloides stercoralis, T. trichiura and hookworms. The most predominant parasite encountered was E. histolytica/dispar (42.9 %) whereas both T. trichiura and A. lumbricoides (2.9 %) were the least detected parasites. None of the fresh vegetables had single parasitic contamination. The highest percentages found in water samples used to sprinkle vegetable(s) was for Strongyloides larvae 60 % (3/5). It is worth-mentioned that the rate of contamination in Elshaabi market was higher compared with Central market. However, there was no significant correlation between the type of vegetables and existence of parasites in both markets and a high significant relationship was observed between the type of parasite and total prevalence in fresh vegetables (p = 0.000). CONCLUSION: The study has identified a moderate rate of fresh vegetables contaminated with protozoan and helminthes. Contaminated fresh vegetables in central markets of Khartoum state may play a significant role in transmission of intestinal parasitic infections to humans, and the water used by greengrocers to sprinkle vegetable(s) can be implicated in vegetable contamination.

Molecular detection of Cyclospora in water, soil, vegetables and humans in southern Italy signals a need for improved monitoring by health authorities.

To date, in Europe, there is scant information on the occurrence of Cyclospora in water from treatment plants and in humans, and no data are available on soil or fresh plant products. Here, we undertook the first molecular survey of Cyclospora in multiple biological matrices collected from the Apulia region of southern Italy. Samples of irrigation water from four municipal treatment plants, eight different types of vegetables or fruit (cucumber, lettuce, fennel, celery, tomato, melon, endive and chicory) and soil from the same farms on which these plants were grown, as well as faecal samples from humans living in the same region were tested by qPCR-coupled single-strand conformation polymorphism (SSCP) analysis and DNA sequencing. Cyclospora was detected in 15.5% of all 213 samples tested. Specifically, this protist was detected in (i) treated water (21.3% of 94 samples), well water (6.2% of 16), but not drinking water (0% of 3); (ii) soil (11.8% of 51 samples) and vegetables (12.2% of 49), with the highest prevalence (18.7%) on fennel; and (iii) human stools (27.5% of 40 samples). In environmental and food samples, Cyclospora was detected mainly in autumn and was significantly more prevalent in the faeces from humans of 40-50 years of age. This is the first comprehensive molecular survey of Cyclospora in environmental, food and human faecal samples in Europe. These data suggest that irrigation water, soil and vegetables might be contaminated by Cyclospora cayetanensis, which might represent a source of infection to humans in the study area and calls for monitoring by health authorities.

Challenges in devising economic spray thresholds for a major pest of Australian canola, the redlegged earth mite (Halotydeus destructor).

BACKGROUND: A key component for spray decision-making in IPM programmes is the establishment of economic injury levels (EILs) and economic thresholds (ETs). We aimed to establish an EIL for the redlegged earth mite (Halotydeus destructor Tucker) on canola. RESULTS: Complex interactions between mite numbers, feeding damage and plant recovery were found, highlighting the challenges in linking H. destructor numbers to yield. A guide of 10 mites plant(-1) was established at the first-true-leaf stage; however, simple relationships were not evident at other crop development stages, making it difficult to establish reliable EILs based on mite number. Yield was, however, strongly associated with plant damage and plant densities, reflecting the impact of mite feeding damage and indicating a plant-based alternative for establishing thresholds for H. destructor. Drawing on data from multiple field trials, we show that plant densities below 30-40 plants m(-2) could be used as a proxy for mite damage when reliable estimates of mite densities are not possible. CONCLUSION: This plant-based threshold provides a practical tool that avoids the difficulties of accurately estimating mite densities. The approach may be applicable to other situations where production conditions are unpredictable and interactions between pests and plant hosts are complex.

Assessment of nurses' performance related to control of some parasites acquired from fresh vegetables as a patient safety measure in a military hospital.

UNLABELLED: Foodborne parasitic infection in the hospital constitutes a major health problem particularly for patients who are more vulnerable than healthy subjects to parasitic risks. Parasitic infection. represents an area of concern for advanced practice nurse. The work assessed the military nursing staff performance regarding the nosocomial food-borne parasitic infection control. SUBJECTS AND METHODS: Research design; A descriptive research design was used to identify knowledge, attitudes and practice of nurses related to nosocomial food-borne parasitic infection control measures. SETTING: The study was conducted at a general military hospital. SUBJECTS: 50 nurses, the whole available number who covered the inclusion, criteria. DATA COLLECTION TOOLS: It included; (1): Structured interview sheet was constructed after reviewing the relevant literature to elicit information, it included two parts a) subjects' sociodemographic characteristics b) nurses' knowledge regarding nosocomial parasites infections. (2): RATING SCALE: to assess attitude of nursing staff towards nosocomial parasites infections and its prevention. (3): Obselrvational CHECKLIST: to assess the nurses' practice of self-protection and' control of nosocomial parasitic' infections control measures.. RESULTS: A statistically insignificant difference between knowledge levels about nosocomial parasites infection among military nurses. More than half of participant nurses had positive attitude towards nosoconijal parasite infection control and prevention without significant difference between all topics (P>0.056). That most participant nurses had unsatisfactory practice to infection control measures with significant lower score for procurement, storage and preparation of raw material followed by personal hygiene (P<0.05). RECOMMENDATIONS: Nurses in all roles and settings can demonstrate leadership in infection prevention. and control by using their knowledge, skill and judgment to initiate appropriate and immediate infection control procedures.

Genetically engineered vegetables expressing proteins from Bacillus thuringiensis for insect resistance: successes, disappointments, challenges and ways to move forward.

Genetically engineered (GE) insect-resistant crops that express proteins from Bacillus thuringiensis (Bt) have been widely adopted in the two field crops currently commercially available, Bt cotton and Bt corn. However, the development and commercialization of Bt vegetables has lagged in comparison, which is unfortunate since vegetables tend to be insecticide-intensive crops due to high pest pressure and cosmetic standards required for the market. While it is often stated that consumer choice has played a major role in companies avoiding development of Bt vegetables, this concept requires re-evaluation. In market studies in North America when consumers have been provided basic information about Bt genetic engineering, then given a choice between Bt and conventional sweet corn, they have often preferred the former. Likewise, 77% of consumers in a US survey said they would likely purchase foods produced through biotechnology for their ability to reduce pesticide use. Presently, however, the only commercialized Bt vegetable is sweet corn. Perhaps more critical obstacles to Bt vegetables are their relatively smaller acreages and the cost of government biosafety regulations that inadvertently favor large acreage of field crops because companies can obtain a better return on investment. In developing countries, private-public partnerships may provide the vehicle to bring Bt vegetables to market. However, these can be subverted by misinformation from anti-biotech campaigns, as is the case with Bt eggplant in India. Without the use of Bt vegetables as a tool for integrated pest management, farmers and the general public will not be able to realize the substantial environmental and economic benefits that have been well documented with Bt cotton and Bt corn.

[Cryptosporidiosis: an emerging zoonosis]. / Criptosporidiosis: una zoonosis emergente.

The genus Cryptosporidium, responsible for producing cryptosporidiosis, includes several species. Humans and livestock are the main sources of infection. Waterborne cryptosporidiosis outbreaks are associated with drinking water. The infective parasite stage is the oocyst, which is resistant to conventional potabilization treatments. In immunocompetent hosts it produces acute, self-limiting diarrhoea. In immunocompromised people, it could develop severe, life-threatening pattern forms of the infection. People with AIDS are especially susceptible to these clinical forms. Cryptosporidium infections are also considered a major cause of morbimortality in calves, which leads to important economic losses. In the last years, there has been an increase of patients suffering from different causes of immunosuppression, and the need to find an effective therapy against Cryptosporidium has become greater. In spite of the many attempts of the pharmaceutical industry to develop an effective antiparasitic agent to treat cryptosporidiosis, this infection and its clinical consequences still constitute a major public health problem. This article analizes the taxonomy, morphology, biology and life cycle of Cryptosporidium. Clinical, immunological, epidemiological features and diagnosis of cryptosporidiosis are also included. Treatment and prevention of the infection are discussed, and future tendencies are suggested for this emerging parasitic infection.

Risk assessment of cryptosporidium and giardia in water irrigating fresh produce in Mexico.

A rise in foodborne outbreaks in the United States associated with fresh produce has resulted in increased concerns with the importation of fruits and vegetables. Mexico is a major exporter of produce to the United States, particularly tomatoes and bell peppers. A quantitative microbial risk assessment (QMRA) was conducted to evaluate the public health impact of protozoan-laden water irrigating produce in Culiacan, Sinaloa, Mexico. Specifically, a QMRA was conducted to address the human health impact associated with consumption of tomatoes, bell peppers, cucumbers, and lettuce irrigated with water contaminated with Cryptosporidium and Giardia. Yearly infection risks were estimated and assumed a 120-day exposure in a given year. Annual risks range from 9 x 10(-6) for Cryptosporidium at the lowest concentration associated with bell peppers to almost 2 x 10(-1) for exposure to Giardia on lettuce at the highest detected concentration. With the relatively high number of illnesses resulting from produce-related outbreaks, addressing pre- and postharvest points of contamination for fruits and vegetables consumed raw should be a food industry priority. This research shows how QMRA can be used to interpret microbial contamination data for public health significance and subsequently provide the foundation for guideline development.

Wastewater-irrigated vegetables: market handling versus irrigation water quality.

OBJECTIVE AND METHODS: Vegetables irrigated with untreated domestic wastewater were, at the time of harvest, analysed for the presence of the faecal indicator, Escherichia coli, and helminth eggs in Faisalabad, Pakistan. Vegetables from the same harvested batch were collected approximately 12 h later from the local market. RESULTS: The survey found relatively low concentrations of E. coli (1.9 E. coli per gram), but relatively high concentrations of helminths (0.7 eggs per gram) on vegetables collected from agricultural fields. Higher concentration of both E. coli (14.3 E. coli per gram) and helminths (2.1 eggs per gram) were recovered from the vegetables collected from the market. CONCLUSIONS: The results of the survey suggest that unhygienic post harvest handling was the major source of produce contamination. Interventions at the market, such as the provision of clean water to wash produce in, are better ways to protect public health and more cost effective than wastewater treatment.

Quantitative assessment of contamination of fresh food produce of various retail types by human-virulent microsporidian spores.

This study demonstrated that fresh food produce, such as berries, sprouts, and green-leafed vegetables, sold at the retail level can contain potentially viable microsporidian spores of human-virulent species, such as Enterocytozoon bieneusi, Encephalitozoon intestinalis, and Encephalitozoon cuniculi, at quantities representing a threat of food-borne infection.

[Current ascariasis situation in the Russian Federation].

In the Russian Federation (RF), ascariasis remains to be the most common geohelminthiasis, in children in particular. With its overall reduction, the prevalence of ascariasis is very uneven on the RF territory. In the past 15 years, from 1991 to 2004, there was a steady-state decrease in the incidence of ascariasis from 79.5 to 46.0 per 100,000. Its incidence rates remained higher than the average Russian ones in 33 RF subjects and lower than those in 48 subjects and began reducing in 8 subjects in the past 4 years. Of the 33 RF subjects wherein the incidence rates were constantly greater than the average Russian ones, 27 subjects are located in the natural background-favorable areas. In the past 15 years, there was an increase in the impact of socioeconomic factors on the higher incidence of ascariasis: the population's migration; the delivery and transport of Ascaris egg-contaminated greens, vegetables, berries; the development of hothouse gardening, and, as a result, the occurrence of ascariasis in the northern areas of the country, as well as the use of discharged waters for soil fertilization to grow crops. The territory of Russia was first epidemiologically districted in the context of ascariasis, by taking into account the natural background and socioeconomic factors. The area of ascariasis is on the rise. In all RF subjects, public health and social security bodies should constantly keep in mind the problem in ascariasis control and prevention.

The potential for acquiring cryptosporidiosis or giardiosis from consumption of mung bean sprouts in Norway: a preliminary step-wise risk assessment.

The current work evolved from a microbial survey of fruits and vegetables conducted in Norway between 1999 and 2001. This survey found that mung bean sprouts were more likely to be contaminated with Cryptosporidium and Giardia than the other produce included in the survey. To support this observation and to demonstrate to public health officials that this might be a risk warranting further attention, a simple risk assessment was initiated. Assuming that 60,000 people in Norway consume a single serving of bean sprouts per week, and contamination levels are similar to those found in the survey, it was calculated that there could be in the order of 20 cases of Giardia or Cryptosporidium infection per 100,000 population attributable to consumption of mung bean sprouts. A number of assumptions were made for the calculations, including parasite factors (e.g. viability, genotype), product factors (e.g. extent of product contamination) and host factors (e.g. composition and extent of consumer group). These assumptions and areas of uncertainty, where further data would improve the risk assessment, are highlighted throughout. Not only does the risk assessment identify new areas of research, but it also demonstrates how risk assessment can be used as a tool to try to influence public health surveillance.

The effect of crop protection strategy on pest and beneficials incidence in protected crops.

This study took place in the Oeste region from 1996-1999 and it intended to analyse if the crop protection strategy followed by the farmer influenced the arthropod incidence and the natural control in protected vegetable crops under Mediterranean conditions. The observations were made fortnightly (Autumn/Winter) or weekly (Spring/Summer) in 30-60 plants/parcel (1 plant/35 m2) in order to evaluate incidences. Samples of pests and natural enemies were collected for systematic identification in two greenhouses for each protection strategy (traditional chemical control (TCC), integrated pest management (IPM) and pest control allowed in organic farming (OF)) in lettuce, tomato, green beans and cucumber. Data on incidence of mites, aphids, caterpillars, leafminers, whiteflies, thrips and respective natural enemies were registered as well as phytosanitary treatments performed (farmers' information and/or in loco traces). The leafminers were the pest whose incidence more often presented significant statistical differences between the studied protection strategies. In relation to this pest, the main results obtained were: a higher feeding punctures incidence in TCC than in IPM; higher incidence of adults, mines and feeding punctures in TCC than in OF; and a higher mines' incidence in IPM than in OF. Both in TCC and IPM high percentages of plants with mines were found although without an adult proportional presence. In the first case this was due to the repeatedly phytosanitary treatments applied; in the second case it was due to the natural control, since in IPM and OF greenhouses the collected larvae were mostly parasitized or dead. In spite of the fact these two strategies have as final result a similar mines and adults incidence, their production and environmental costs are quite different. Significant differences at the beneficials' population level between TCC greenhouses and IPM or OF greenhouses were found. As the farmers did no biological treatments these differences are related to different levels of beneficial populations due to different secondary effects of the pesticides applied.

Assessment of Helicoverpa Armigera resistance to pyrethroid insecticides in northern Cameroon.

In Central Africa savannas, the noctuid Helicoverpa armigera (Hübner) is a major pest of cotton and vegetable crops (including tomato and okra) which directly affects production by attacking fruit-bearing organs. In order to prevent and anticipate problems, the national cotton company (SODECOTON), with the help of the agricultural research (IRAD-PRASAC), implemented in 1999 a monitoring network for the early detection of resistance of target insects to the main recommended insecticides. Over the last three years, from 1999 up to 2001, assessment of H. armigera susceptibility to pyrethroid insecticides was carried out through both vial tests and topical bioassays. Revealed in southern and western Africa, pyrethroid resistance now seems to affect Central Africa also. Although control failure due to resistance has not yet been reported from the field, these results indicate the presence of resistant genes within H. armigera populations in Northern Cameron. Further laboratory studies confirmed the loss of susceptibility to cypermethrin in wild populations. Priority actions to be developed must focus on the rational and concerted management of pesticide use and the implementation of a regional monitoring network for the early detection of the loss of sensibility of target insects to the main recommended insecticides. At the same time, more fundamental research should be undertaken on the epidemiological profile of resistance in order to define practical ways of reducing the selection pressure.