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Sampling > Microbiological Surveillance Sampling

FDA Sampling Assignment Update Identifies Cyclospora in Herbs

August 29, 2018

A risk-based, preventive approach to food safety is at the core of the FDA Food Safety Modernization Act (FSMA). For many years, FDA has used product sampling and testing as one tool to better characterize microbial risk. Beginning in 2014, the agency began developing a new, more robust approach to sampling assignments to assess microbial contamination in food commodities. Under this new approach, the FDA collects a statistically-valid number of samples of targeted foods over a shorter period of time (12-18 months) to help identify common factors among positive findings.The sampling design for each food takes into account the volume of the target food that is both imported and produced domestically, and the number of states/countries that produce the target food, to reflect what U.S. consumers are likely to find in the marketplace.

Commodities sampled to date under the new approach have included sprouts, whole fresh avocados, raw milk cheese, cucumbers, and hot peppers. For fiscal year 2018, the FDA has been sampling fresh herbs, specifically basil, parsley, and cilantro, along with processed avocado and guacamole, with samples coming from both domestic and imported sources. Fresh cilantro, parsley and basil are typically eaten without having undergone a ‘kill step’ (such as cooking) to reduce or eliminate pathogens and are grown low to the ground, making them susceptible to contamination. The sampling assignment was developed to allow FDA to obtain baseline estimates of the prevalence ofSalmonella and Shiga toxin-producing E. coli (STEC) in these herbs.

The agency added to this sampling assignment its recently developed and validated new analytical method to test for the parasite Cyclospora cayetanensis. Cyclospora has caused outbreaks in the U.S. linked to imported produce, including basil and cilantro. Although it’s unknown exactly how food and water become contaminated with Cyclospora, prior outbreaks have been associated with produce grown under insanitary conditions. This highlights the importance of strong sanitation and worker hygiene practices to prevent contamination, since rinsing or washing food is not likely to remove the parasite.

The results of this increased surveillance sampling so far this summer have been that two samples of cilantro offered for import from two producers in Mexico were positive for Cyclospora. In response to the finding, FDA refused entry for these shipments, and will take action to prevent contaminated cilantro from those firms from entering the U.S. As part of a broader effort under theFDA Produce Safety Partnership with Mexico, the two countries are working closely to investigate the cause of contamination.

Domestically, a cilantro sample collected at a distributor in July tested positive for Cyclospora. Following that finding, FDA initiated an investigation and another sample was collected on the farm that also tested positive forCyclospora. In response, the FDA worked closely with state officials to voluntarily recall and embargo potentially affected product, and has been working with the farmer on corrective actions geared toward common routes of contamination.

Although this is the first confirmed evidence of the presence of Cyclospora in domestic produce, FDA is currently unaware of illnesses associated with the product, and traceforward efforts do not indicate there are any connections between this domestic finding of contaminated cilantro and multistate outbreaks of Cyclospora illnesses investigated this spring and summer.

The findings of Cyclospora in both domestic and imported produce highlight the importance of FDA’s surveillance activities to better define risks. These findings also highlight the importance of implementing the provisions of FSMA’s Produce Safety Rule at home and abroad to reduce risk and prevent illnesses from occurring. The Produce Safety Rule is designed to put in place science-based measures to prevent microbial contamination from occurring. State and foreign partners have an important role in working with the FDA to implement the rule. These partnerships and others enhance FDA’s ability to act swiftly to detain and remove any contaminated product from commerce, protecting U.S. consumers, as happened after the findings in domestic and imported produce.

FDA will continue to inform consumers as additional information becomes available regarding investigations and other work related to Cyclospora.

Microbiological Surveillance Sampling

Testing to Support Prevention Under the FDA Food Safety Modernization Act

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As part of the FDA’s risk-based and preventive approach to food safety, which is at the core of the FDA Food Safety Modernization Act, the agency began developing a new, more robust approach to deploying its sampling resources in 2014. As the agency moves forward with this approach, it will continue to refine procedures based on lessons learned. The goals of the surveillance sampling are to keep contaminated products from reaching consumers and to facilitate a greater understanding of hazards.

The FDA will publish information regarding test results on the web, including total number of samples collected/tested, and collection date, sample type, and pathogen detected for positive samples.

• The Sampling Approach
• Commodities Sampled
• Using the Data
• FY18 Fresh Herbs (Cilantro, Basil & Parsley) and Processed Avocado and Guacamole
• FY16 Cucumbers and Hot Peppers
• Summary Report: FY14-16 Raw Milk Cheese Aged 60 Days
• Summary Report: FY14-16 Sprouts

The Sampling Approach

Under the new sampling approach, the FDA is collecting a statistically determined number of samples of targeted foods over a shorter period of time—12 to18 months—to ensure a statistically valid amount of data is available for decision making.  The sampling approach will help the FDA determine if there are any common factors among positive findings such as season, region, and whether the product was produced domestically or imported.  The FDA’s past approach to microbiological surveillance sampling has been to collect a relatively small number of samples for many different commodities over many years. 

The sampling design for each food represents what U.S. consumers are likely to find in the marketplace. Accordingly, the agency has considered the volume of the target food that is imported and produced domestically and the number of states/countries that produce the target food.

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Commodities Sampled

During the first year of this new effort, the FDA focused on sprouts, whole fresh avocados, and raw milk cheese (aged 60 days). The FDA collected more than 800 samples of each commodity and tested them for Salmonella, Listeria monocytogenes and E. coli O157:H7. For fiscal year 2016, the FDA is sampling and testing cucumbers and hot peppers for Salmonella and E. coli O157:H7, taking 1,600 samples of each commodity. The agency also tested hot peppers for Shiga toxin producing E. coli. For fiscal year 2018, the FDA is sampling fresh herbs, specifically basil, parsley, and cilantro, to test for Salmonella, Shiga toxin producing E. coli, and may test for Cyclospora cayetanensis during certain months; sampling processed avocado and guacamole to test for Salmonella and Listeria monocytogenes.

The FDA will conduct whole genomic sequence testing on any samples that test positive. In the future, the number of samples collected of a targeted commodity may vary, depending on the question(s) the FDA intends to answer.

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Using the Data

The FDA will evaluate the data or results generated throughout the sample collection period and use the data to inform the agency’s short and longer term decision making. By developing these data sets, the FDA seeks to identify potential vulnerabilities and ways to enhance the food safety system.

Depending on the results, the FDA may react or take certain steps, such as:

• Decreasing sampling, if few positive samples are obtained;
• Implementing more targeted sampling if trends are identified; for example, if positive samples come from a specific geographic region, a specific facility, or during a particular season;
• Follow-up inspections;
• Working with state or international regulatory partners to take corrective actions and implement preventive controls;
• Developing new or enhanced industry guidance; and
• Conducting outreach and information sharing to better protect consumers.