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  5. Microbiological Surveillance Sampling: FY18-19 Fresh Herbs (Cilantro, Basil & Parsley) and Processed Avocado and Guacamole Assignments
  1. Sampling to Protect the Food Supply

Microbiological Surveillance Sampling: FY18-19 Fresh Herbs (Cilantro, Basil & Parsley) and Processed Avocado and Guacamole Assignments

Microbiological Surveillance Sampling


Fresh Herbs (Cilantro, Parsley & Basil)

Fresh cilantro, parsley and basil are typically eaten without having undergone a ‘kill step,’ such as cooking, to reduce or eliminate bacteria. These herbs are grown low to the ground and therefore are susceptible to contamination (e.g., from irrigation water splashing off the soil).

From 1996 to 2015, the FDA reported nine outbreaks linked to basil, parsley and cilantro, which resulted in 2,699 illnesses and 84 hospitalizations. Four of the outbreaks were linked to basil, three to cilantro, and two to parsley. Of those same nine outbreaks, seven were attributed to Cyclospora cayetanensis; one was attributed to E. coli O157:H7; and one was attributed to Shigella sonnei. The FDA is seeking to obtain baseline estimates of the prevalence of Salmonella and Shiga toxin-producing E. coli (STEC) in cilantro, basil and parsley.

In addition, given that Cyclospora-related illnesses typically occur in the summer, the FDA began testing fresh herb samples for Cyclospora cayetanensis in July 2018 to estimate the prevalence of that microorganism in basil, parsley and cilantro. Surveillance sampling is an important tool that the FDA and the Centers for Disease Control and Prevention (CDC) are using as one part of a robust strategy to prevent illnesses caused by Cyclospora. Read more on cyclosporiasis and fresh produce.

Processed Avocado & Guacamole

Avocados have a high lipid and moisture content, low carbohydrates, and non-acidic pH level, which can make them a favorable growth medium for harmful bacteria. Processed avocado products, including avocado that is fresh cut, refrigerated and frozen, may be packaged and eaten without having undergone a ‘kill step’ prior to consumption. In addition, processing fresh produce into fresh-cut products increases the risk of bacterial growth by breaking the fruit’s skin and allowing for the spread and potential growth of any pathogens that may be present.

According to the CDC, there were 12 outbreaks of foodborne illness related to avocado, avocado products or guacamole products from 2005 to 2015. Of those 12 outbreaks, nine involved Salmonella and three involved E. coli, resulting in 525 illnesses and 23 hospitalizations in all. Though no Listeria outbreaks were reported in connection with avocados from 2005 to 2015, a recent sampling assignment by the FDA detected Listeria monocytogenes in samples collected from the fruit’s pulp and skin. The agency is seeking data on the prevalence of Salmonella and Listeria monocytogenes in processed avocado and processed avocado products.

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Questions and Answers

When will the FDA collect samples?
The FDA began collecting samples of these commodities in October 2017 and plans to continue its collection until it has met its targets of 1,600 samples for fresh herbs, and 1,056 samples for processed avocado and guacamole. The sample collections are anticipated to take about two years. Sampling will occur primarily Monday through Thursday, throughout the year.

Where will the samples be collected from?
The FDA will collect samples of imported fresh cilantro, parsley and basil from ports of entry, importer warehouses, or other storage facilities where foreign goods are cleared for entry into the country, and domestic samples from packers (including post-harvest products in packinghouses on farms), wholesalers, distributors/warehouses and retail locations. Retail samples will be collected from dealer storage (i.e., prior to consumer handling). The FDA will collect samples of imported processed avocado and guacamole from ports of entry, importer warehouses, or other storage facilities, and domestic samples from processors, distributors and retail locations.

What exactly do you plan to collect?
For fresh herbs, the FDA plans to collect fresh, raw parsley, cilantro and basil. The agency does not plan to collect frozen, chopped, or dried herbs, or fresh herbs indicated as intended for processing. The FDA plans to collect processed avocado, including fresh cut, pureed, refrigerated and frozen product, as well as frozen avocado pulp with additives, and guacamole. The agency does not plan to collect whole avocados (intact, with skin). The FDA will not collect samples from farms or growers, product indicated as intended for beverage(s), product that has undergone a pathogen reduction step, such as pasteurization, or product intended to be further processed with a pathogen reduction step.

What will the FDA test for?
The FDA is testing both fresh herbs (cilantro, basil and parsley) and processed avocado and guacamole for Salmonella. The agency also is testing fresh herbs for STEC and processed avocado and guacamole for Listeria monocytogenes. Finally, the agency also began testing its fresh herb samples for Cyclospora cayetanensis in July 2018 given that Cyclospora-related illnesses typically occur in the summer. The FDA also will conduct whole genome sequence testing on any samples that test positive to obtain the genetic ‘fingerprint’ of the pathogen and will add the resulting information to the databases used to match human illnesses with potential food sources.

Will the FDA provide pre-notification to facilities where it plans to conduct sampling?
Per standard FDA practice, the agency will not provide pre-notification to firms prior to collecting samples, except if the sample collection is to occur at a packinghouse located on a farm. (All fresh herb sample collection is to occur after the produce has been harvested.) When a member of the FDA field staff is planning to collect fresh herb samples from an on-farm packinghouse, the agency employee will call the farm at least 24 hours in advance to notify the owners or operators. Sampling is a routine and critical activity that the FDA is authorized to conduct as part of its charge to ensure the safety of the food supply.

What happens when the FDA finds a positive sample?
When the FDA detects a positive sample, the agency will notify the firm of the findings and work with the firm to take appropriate action to protect the public health. Enforcement activities include actions to correct and prevent violations and to remove violative food from the market, as appropriate.

What should I expect when the FDA collects samples?
See detailed information on what to expect when the FDA collects samples.

Will the FDA publish the test results? If so, how often?
The FDA plans to publish the test results on a quarterly basis. Check here as they will be posted at the bottom of this page.

What is the FDA doing to minimize the impact of its sampling on trade and commerce?
The FDA is sensitive to the concerns of both domestic firms and importers and strives to provide analytical results to industry as soon as they are available. The FDA will notify all firms of analytical results as soon as possible once sample analysis is complete.

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Results as of 7/1/2019

The FDA began collecting and testing fresh herbs (cilantro, parsley and basil) and processed avocado and guacamole in October 2017. These two assignments are anticipated to last about two years. The information that follows presents the laboratory results through June 30, 2019, as interim figures subject to potential revision. The FDA will publish summary reports of its results (to include final figures and breakdowns of its findings) once the assignments have been completed. People who wish to see an example report on the FDA’s food product surveillance sampling can view the agency’s report on its sampling of sprouts.

The sampling design for each food represents what U.S. consumers are likely to find in the marketplace with respect to product origin (i.e., domestic vs. import). Accordingly, the FDA has considered the volume of the target food that is imported and produced domestically, and which countries produce and export the food to the United States. The FDA may adjust the number of samples to be collected or the collection timeline based on factors that the agency may encounter during the assignments.

In the event that samples are found to be positive for microbial hazards, the FDA will consider regulatory and enforcement options, which include: encouraging a voluntary recall or market withdrawal, ordering a mandatory recall, ordering administrative detention to prevent food from being distributed, issuing public warnings to alert consumers to the potential danger, and in the case of imported products, refusing their entry into the country and subjecting future shipments to an import alert. The agency will detail any enforcement action it takes in its summary report(s).

Fresh Herbs Results as of 7/1/2019

The FDA plans to collect 1,600 fresh herbs samples (761 domestic, and 839 of international origin) under this assignment. As of June 30, 2019, the agency had collected and tested 521 domestic samples (68 percent) and 437 import samples (52 percent) of the totals. The following figures summarize the interim sampling results. As the testing is still underway, no conclusions can be drawn at this time.

Herb Sampling Results 07012019

Processed Avocado and Guacamole Results as of 7/1/2019

The FDA initially planned to collect 1,600 processed avocado and guacamole samples (800 domestic, and 800 of international origin) under this assignment. In July 2018, the FDA adjusted its collection target to 1,200 samples (936 domestic, and 264 of international origin) after initial sampling confirmed that a relatively small number of firms produce and/or distribute processed avocado. The agency’s intent was to avoid biasing the data by oversampling product from the same firms and to minimize the burden on industry. Further, the FDA learned that an increasing number of processors have begun to use high pressure processing, which is a kill step. In March 2019, the FDA further reduced its collection target to 1,056 samples (824 domestic, and 232 of international origin) given the 35-day lapse in appropriations that began on December 22, 2018, and the associated impact on the workload of the agency’s field staff. The new collection target, as compared to the original, increases the margin of error of the prevalence estimate from 0.5 to 0.6 percent.

As of June 30, 2019, the agency had collected and tested 584 domestic samples (71 percent) and 101 import samples (44 percent) of the new targets. The following figures summarize the interim sampling results. As the testing is still underway, no conclusions can be drawn at this time.

Processed Avocado and Guacamole Sampling Results as of 07012019

Additional Information