Fresh produce and microbial safety concerns

Transcription

1 Fresh produce and microbial safety concerns Mieke Uyttendaele 1 Vittorio Fattori 2, Marisa Caipo 2, Lee-Ann Jaykus 3 1 Dept. Food safety & Food Quality, Faculty of Bio-Science Engineering, Ghent University, Belgium 2 Food Safety & Quality, FAO, Rome, Italy 3 North Carolina State University, US & ILSI Water and Sanitation Expert Group

2 Fresh produce, part of a healthy diet 2

3 Global sourcing of fresh produce ISHS Harvesting the sun: a profile of world horticulture.

4 Food safety incidences,also with fresh produce EHEC outbreak in Germany/France in May/July 2011 Scare on Hepatitis-sundried tomatoes from Turkey (Nethl., Austr ) Not cucumbers from Spain but Fenugreek seed from Egypt EU RASFF : Norovirus in (frozen) raspberries

5 Food safety incidences,also with fresh produce VTEC EAggEC (EHEC outbreak in Germany/France in 2011), Norovirus & Hepatitis A virus, as well as Shigella sp. are human specific bacterial pathogens Workers hygiene! Also for the food handlers source of contamination, water might be or is an extenuating circumstance. Water, or rather the lack of access to clean water to wash hands and have properly functioning sanitary facilities at its disposal will contribute to spread of pathogens on produce by insufficient hygienic practices

6 Pre- and postharvest production practices Produce contamination is more likely to occur when workers habits are less than hygienic when crops are grown in soil containing pathogens, when soils are fertilized with untreated liquid or solid manures, and when non-potable water is used for irrigation or formulating pesticides for use in crops Wild life / Livestock! (Factors influencing safety of fresh produce: a review: Olaimat & Holey, Food Microbiology , 1-19) 6

7 Water as a source of contamination Spinach-associated Escherichia coli O157:H7 Outbreak in US (2006) the river functioned as a vector between the contaminated feces and the irrigation wells Jalapenos peppers Salmonella Saintpaul, US (2008) The outbreak strain was isolated from two environmental samples, agricultural water, and Serrano peppers on a farm in Mexico which grew the peppers S. Newport & tomatoes in US (2002, 2005) : the outbreak strain was traced back to farms on the Eastern Shore of Virginia, specifically to on-site ponds used for irrigation water

8 Water as a source of contamination Australia (2006): papayas and Salmonella Litchfield : washed with water from a source later determined to contain other serotypes of Salmonella US/Canada (1996) berries and Cyclospora cayetanensis: spraying with pesticides or fungicides prepared using contaminated water US (2011) melons and Listeria monocytogenes : water/wet surfaces in processing environment facilitates survival and persistence

9 Causative agent. Year Countries Cases Implicated food Import? S. Newport 2012 UK, IRL, GE 54 Watermelon Brazil S. Newport 2011 GE, Nethl. 106 Sprouted seeds Netherlands S. Strathcona 2011 Denmark 40 Datterino tomato Italy S. Senftenberg 2007 UK 30 Basil Israel S. Thompson 2004 Norway 21 Rucola Italy S. Braenderup 2004 UK 40 Iceberg lettuce Spain E. coli O UK 250 Leeks/potatoes Domestic E. coli O Nethl & Icel 50 Lettuce mix Domestic E. coli O Sweden 135 Iceberg lettuce Domestic Shigella sonnei 2011 Norway 46 Basil Israel Shigella sonnei 2009 Noway/DK 30 Sugar snaps Kenya Yers. enteroc Norway 21 Salad mix Italy Cyclospora sp Sweden 18 Sugar snaps Guatemala Cryptosporidium 2005 Denmark 99 Salad bar Domestic. 9

10 Water as a source of contamination Sweden (2005) iceberg lettuce and E. coli O157: irrigated by water from a small stream & cattle at a farm upstream from the irrigation point Data availability on outbreaks associated with fresh produce and in particular detailed information on outbreaks & sources of contamination is diverse and scattered. For many outbreaks the (likely) source of contamination is unknown Outbreak data are only available as of developed countries due to the lack of well functioning surveillance and reporting system in many developed countries. But also in developed countries, outbreak investigation may differ geographically

11 Microbiological hazards Salmonella Norovirus E. coli O157 Non O157 VTEC Shigella Hepatitis A Cyclospora Campylobacter Yersinia enterocolitica Giardia Cryptosporidium Listeria monocytogenes

12 Protozoa, viruses & helminths They are known causes of human diarrhea and illness particular in developing countries In the case of protozoa, standardized and accessible methods for detection in fresh produce are currently not available which may explain the restricted number of reports to be found linking Cryptosporidium, Cyclospora andd Giardia as a food borne pathogen linked to consumption of fresh produce. The same for some enteric viruses (rotavirus, echovirus, poliovirus) & helminths which are not standard part of suspected causative agents in outbreak investigation in many countries

13 Lack of access to clean water / water treatment in local conditions impacts on safety of fresh produce it has been shown, in some countries such as Senegal, South Africa, Mexico and India that the quality of the irrigation water (and the manures used on the field) and the quality of water for washing (and the renewal time of water used) and to maintain the freshness of lettuces and other crops before sale influences the microbial quality of produce (presence of fecal indicator organisms and pathogens) displayed at the marketplaces and thus for consumption by the local inhabitants. (Ndiage et al Irrig. and Drain. 60, ; Ljabadeniyi et al J. Food Safety 31, ; Castro-Rosas et al Int. J. Food Microbiol. 156, ; Minhas et al Bioresource Technology 97, ).

14 Water, one of many sources of pathogens in fresh produce

15 Water, one of many sources of pathogens in fresh produce

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