Food Safety Magazine - June/July 2018

reductions in the test volumes. Those large companies that have been doing fewer samples will be dramatically increasing their test volumes from perhaps tens to up to hundreds of samples per week. Many of these companies include a few large companies with multiple locations.

We spoke to several of these processors to get more information. One processor that indicated that they were planning to reduce their EM sample volumes told us that they were changing their program to take a more focused approach. They had been taking several hundred samples each week throughout the plant, but this changed about 2 years ago. At that time, they adjusted their EM program to collect fewer samples for pathogen analysis in key problem areas, or, as they indicated, they adjusted from a “shotgun” to a “rifle” approach. The sample sites were developed using data collected over previous years; this approach allowed them to identify key problem areas and reduce the sampling they conducted in those areas, which were shown to be under better control.

Intensifying Efforts against Listeria

In other interviews, processors told us about their plans to dramatically increase their Listeria sampling, particularly their EM sample volume. One company reported that they are dramatically changing their program, with an aim to find and eliminate Listeria harborage sites and as a response to the FDA guidance released in 2017. Their plan will include increasing their overall EM sampling volume approximately twofold. They reported that all EM testing will increase, including tests for other pathogens, but the primary driver of the increase will be Listeria, mentioning that “we had been doing hundreds of Listeria samples per month and will now be doing hundreds of samples per week.” They also mentioned that end-product testing will increase somewhat, but less than 10 percent, and routine microbiology will be unchanged.

Another company we spoke with
reported a similar plan: Later this year,
they will be increasing their EM test
volume significantly, but the numbers
of samples for Listeria that they collect
at each plant will increase from tens to
hundreds of samples each week.

Another company planned to take a somewhat different approach. A few years ago, in anticipation of regulatory and inspection changes, they increased their EM sampling and doubled the number of samples that they were collecting for both Salmonella and Listeria. Although they were regularly collecting EM samples, most of the increase in their sample numbers came from “seek and destroy” sampling programs that they conducted three times per year. They found this to be an effective way to hunt for difficult areas that may have been missed by routine sampling. Following their FSMA compliance date, they received an FDA inspection that included a “swab-a-thon.” They were happy to report that the FDA sampling found no positive samples, but they nonetheless increased their sampling projects to quarterly, further increasing their overall volumes another 10–15 percent.

Many will be wondering where these samples will be analyzed. As we have seen in the past, where companies send their samples for analysis largely depends on their sample volumes. As shown in Figure 2, smaller and midsize users overwhelmingly send their samples out to a commercial lab, but above the 100-samples-per-week threshold, the balance tends to favor using a centralized corporate lab or an in-plant lab. This figure shows the selection based on the number of facilities, but when the data are weighted for volume, the number of samples being sent to commercial labs is roughly 50–55 percent of the total sample volume in the survey. This is expected, as the few, very large facilities with high sample volumes tend to have access to a central lab or in-plant lab, whereas the higher-number-but-smaller-volume users are much more likely to send their samples to an outside lab.

This is consistent with the data we re-
ported in December-January 2017, in
which approximately two-thirds of pro-
cessor locations will primarily outsource
sample analysis, but this results in a
50/50 split in terms of overall pathogen
sample volume.

An Opportunity for Testing Labs
Based on the data from this survey,
as well as data that we have collected
for other projects, we anticipate that
sample analysis for Listeria will be the
fastest growing category in food safety
microbiology for the next few years. As
the largest companies set the standard,
others will follow, and we would expect
this trend to continue for the next 2 to
3 years until companies have completed
the adjustments of their programs and
growth levels off at this increased level.

This increase in demand for Listeria tests will drive competition in the diagnostic and laboratory market, and we can expect to see new products and offerings emerge to capture this new demand.

Processors are clearly attacking the Listeria issue. It is now up to the diagnostic companies and laboratories to help them meet the challenge. n

Bob Ferguson is the managing director of Strategic Consulting Inc. and can be reached at foodsafetyinsights@gmail.com or on Twitter at @SCI_Ferguson.