E2M2C: To Assay, or Not To Assay… A Difficult Question of Great Importance

This article by Jerry Cates, first published on 11 June 2021, was last revised on 17 October 2022. © Bugsinthenews Vol. 23:06(01).:

Click Here for: Important Notice about the E2M2C™ trademark , the Ownership, Placement & Servicing of E2M2C™ Devices, and Program Participation/Termination

In the original posting of this article, below, I explain why, back in June of 2021, we temporarily halted our assays of the E2M2C™ devices involved with rodent control, during servicing of those devices in our lab. The reasoning behind that hiatus was and is unassailable. However, we know all too well that those assays provided essential information needed for our on-going research, as well as for informing our clients about the nature of the rodent activity at their sites. Without that information, our research and development programs suffered, and our participating clients were left in the dark.

The E2M2C™ program works wonders, but the costs are not trivial. Participating clients need to know if the E2M2C™ program, as originally configured, is still needed for their sites. Once their obvious rodent issues are resolved, and now all those rodents are gone and new ones are not showing up, continued participation might be a waste. If new rodents are still showing up, but in small numbers, maybe the program should be adjusted to reduce costs.  An analysis of the amount of rodent activity over time in each device, showing where the device was positioned when that activity took place, would answer these questions. All our clients understood why we paused the assays, but they still needed answers. Here are some of the questions we’ve been asked since that day in June of 2021:

“Do we still need the E2M2C™ program, or have the rodent issues that prompted us to enroll in the E2M2C™ program already been solved for good?

“If the program is still needed because fresh rodents keep arriving from surrounding areas, do we really need all those devices, or — assuming the number of rodents now visiting our site had diminished — could we now get by with less?”

“What about the service interval? Can it be extended beyond the standard once-every-four-months service schedule, to reduce our servicing fees?”

Good questions, all deserving of good answers. 

We’ve continued to study all the scientific papers we can get our hands on that deal with commensal rodent biology. We’ve also kept up-to-date on technological advances in rodent monitoring and control within the pest management industry. What we’re learning is three-fold.

First, almost none of the conclusions offered by the extant literature — including those gleaned from the most recent papers published here and abroad — correlate well with our observations in the field. Wondering why, we examined the investigative methods used to reach those conclusions. In practically every case the investigators failed to collect truly objective data based on the real-world conditions. Although praised for the reams of data those studies collected, little of that data was empirical. Instead, most emanated from face-to-face interviews with home and business owners, and cursory inspections for evidence of nests and fecal pellets. In our experience, while interviews and inspections are a necessary first step in any rodent control program, they paint an amazingly incomplete — and often inaccurate — picture of rodent-related activity. In fact, we have learned that only by carefully monitoring nutrient pilferage, by the rodents that visit a given locale over time, can an accurate picture of rodent prevalence and abundance emerge.

Second, few of the objective investigations into rodent behavior, conducted by trained observers, utilized wild rats and mice in their native habitats. Instead, laboratory rats and mice, in laboratory settings, served as models. The behavior of those rodents, living within simulated environments under laboratory conditions, cannot be correlated with the behavior of their wild rat and mouse cousins. Any attempt to do so will produce untrustworthy results. 

Third, although new technologies are being added to the latest rodent management stations being placed on the market, and hawked as advances in rodent monitoring and control, the underlying technologies involved suffer from a myriad of defects. Some of the deficiencies we’ve found will likely be corrected as the technologies mature, but others — a few of which are of crucial importance to the data collection paradigm — appear fatally flawed.

Adding specialized sensor technology to existing rodenticide dispensing and/or euthanizing stations is so costly that basic design defects in the station itself are ignored or overlooked. We’ve identified a number of significant design defects affecting not only the rodenticide dispensers & euthanizing stations presently on the market, but affecting the way those stations are serviced as well. The defects we’ve uncovered keep many rodents from going into them, and for those that do, the same defects prevent many that go in from taking the baits or triggering the euthanizing devices the stations contain. 

Not only that, but non-target animals, including humans and their companion pets, frequent the spaces where these technologically advanced stations are positioned and manipulate them in ways that trigger the stations’ sensors.  Such triggers are indistinguishable from the ones produced by rodents. This nullifies any virtue the technology might otherwise bring to the table.

E2M2C™ solves that challenge, not only by using specially designed, defect-free devices that all rodents find inviting, inside and out, but with a unique servicing protocol that takes the monitoring task to the laboratory, where — instead of relying on crude electronic triggers — specially trained analysts record trustworthy, objective, irrefutable observations.

While incidental to their primary purpose (rodent control) our E2M2C™  devices are designed and serviced in a way that allows them to  perform as excellent monitors of wild rodent activity. By assaying those devices every time they are serviced, we are able to collect data on everything a scientific study needs to to keep track of rodent activity. The E2M2C™ program is now in place all over Texas. Done right, assays of its devices should provide excellent insight into rodent prevalence and abundance wherever the E2M2C™ program is in operation.

We’ve constantly improved the sanitization protocols at our lab since the Covid 19 pandemic hit. Today we feel confident our resumption of assaying our E2M2C™ devices can be done without exposing our laboratory personnel to untoward risks. We’re conducting a limited amount of assays now, and perfecting the assay protocols to ensure the right information is collected and properly interpreted. 

The E2M2C™ program has all the components needed to conduct in-depth quantitative and qualitative scientific inquiries regarding rodent biology, ecology, and ethology. Knowing that, when our clients first asked for details on precisely where, and how much rodent control product had been consumed at their sites, we went to great lengths to access those components and, using the data they provided, did everything in our power to comply. Based on how the E2M2C™ program works, we felt all the information our clients wanted — and more — was readily available. We’d simply tabulate it, then pass it on.

Naive Expectations…

I even stoked expectations we’d supply that information to our clients on demand. There seemed to be no obvious downsides, and lots of good reasons to share all that information without limitation. My research was producing exciting results. Our E2M2C™ devices bring serious rodent infestations under control in days. We succeed in places where nothing else will. We’ve never failed, even with serious rodent infestations that had been going on — uninterrupted — for 15 years or more. In many cases the client had hired as many as five, seven, even ten different pest management companies, all of whom had failed to solve their rat issues, before they finally called on us. Then, usually within days after we’d put the E2M2C™ program in operation, no more rats... How the E2M2C™ program accomplishes these feats needs to be told. An enticing body of information, on that very subject, lies right at our fingertips.

At least that’s what I thought… Then, Murphy’s Law intervened and I had to re-think the whole problem. Yes, the results of the E2M2C™ program are nothing short of miraculous. The quality of this program is without dispute. But quantifying those results in numerical terms? Well, that’s another question entirely.

Murphy’s Law in Action…

But, dang! It seemed like such a simple thing for us to do. That should have been my first clue. Remember Murphy’s dictum “Nothing is as simple as it looks…”? I’m here to tell you, Murphy was right.

I’ve found Murphy’s law to be more often right than wrong in practically every sphere of knowledge that I’ve investigated. But, like most endeavors in life, sometimes things actually are as simple as they look. When that happens, it can be a blessing, or it might just end up leading you down the proverbial garden path.

For example, each rodent control product we use has an original unit weight, out of the package, that varies within a narrow range. The amount needed to neutralize a typical rodent is well known. We can record the weight when it is placed in the device, then weigh what’s left after use. The difference would estimate — albeit roughly — how many rodents were neutralized. Wherever lots of consumption had taken place, weighing the residue is quick and easy. Then, extrapolating from that, we can just as quickly estimate how many rodents had been neutralized at that site over the known placement interval.

That’s simple enough, right? Where most of the product has been consumed, and during extended periods of moderately cool, dry weather, it is. Where less of the product is taken, and during periods when temperatures rise and wet weather prevails, however, there’s nothing at all simple about the process.

Dashed by A Dose of Reality…

Our E2M2C™ devices keep rodent control products palatable for extended periods in the field. This is true even under high-moisture conditions. But excess humidity, even below the level required to compromise palatability, is still absorbed into the product. This added mass varies over so wide a range that we soon figured out that — for all instances where not all the bait had been consumed — weight, alone, cannot be used to accurately estimate consumption. We’ve tested other methods, but each introduced its own brand of subjectivity where objective truth was paramount.

Frustrated by this discovery, I initially thought it a bad thing. We had failed to handle a trivial data collection and analysis job. Today, however I view that discovery in a much more positive light.

By focusing on data collection, I’d risked diverting attention away from sterile procedure. Of the two, I knew the latter took priority. I’d hoped to attend to both in equal proportions. That, I learned, is not possible. One cannot be handled well without neglecting the other.

Getting Our Priorities Straight…

Assays of E2M2C™ devices returned from the field require that someone — our lab personnel — transfer  product, as it is removed, via a complex protocol. I won’t bore you with all the details here, but containers, labels, forceps, scissors, personal protection equipment, and precision lab scales get exposed along the way. Protecting those who do that requires a carefully-orchestrated process that limits contaminating the lab and our employees with pathogens the rodents may have left behind. Being a complex process, unintentional mistakes easily occur, even under the best of circumstances.

The outer shell of each used E2M2C™ device is as free of parasites and pathogens as ordinary surfaces within the general environment. By comparison, the deep recesses inside these devices often carry rodent ectoparasites — e.g., fleas, ticks, lice, and mites — each possibly infected with their own endoparasites, bacteria, and viruses.  Rodents inside E2M2C™ devices contaminate their interiors with urine and feces. Those carry some or all the endoparasites, bacteria and viruses common to rodents. Many can cause disease in humans and our companion pets. Those diseases are not trivial but are among the most dangerous known to man.

Protecting the personnel who swap out used E2M2C™ devices with sanitized re-provisioned ones must start at the client’s site.  Each device gets sealed, at once, in a 3-mil plastic bag along with a sterilant. The sterilant neutralizes ectoparasites inside the device on the way to the lab. Bacteria and viruses, though, continue to pose a risk of cross-contamination to those who open, clean, sanitize and re-provision each device.

Things Even a Level 4 BioSafe Laboratory Couldn’t Prevent…

Cross-contamination is the transfer of a pathogen from one surface or substance to another, previously un-contaminated surface or substance. Examples of catastrophic contamination events, that resulted in human disease and fatalities, abound in scientific literature. For example, the human H1N1 influenza virus behind the 1918 pandemic was considered extinct by 1957.

Still, specimens of the original virus were held in carefully controlled laboratories throughout the world.

In 1977 human H1N1 influenza virus resurfaced in the Soviet Union and China. Though it took 33 years to do so, genomic analysis of the virus eventually confirmed, in 2010, that this virus had the un-mutated genetic sequence of the original virus from 1918. Only a laboratory escape, of a specimen held in a laboratory for decades, could explain its reemergence. 

Mistakes Regularly Happen at The Best Laboratories in the World…

Even the U.S. Centers for Disease Control and Prevention (CDC) is not immune, as a published report (one of many, if you care to search the Internet) on the inadvertent cross-contamination and shipment of a laboratory specimen with Influenza H5N1, dated 2014, points out. The cause? “… (it) most likely happened due to the failure of a laboratory scientist to adhere to established best practices…” When working with this kind of material, even minor mistakes can produce disastrous results. In this particular case, the incident appeared not to have posed a safety risk because the specimen was handled solely under laboratory conditions. But, had this virus been released into the environment, catastrophic events could easily have unfolded.

While effects from the above-mentioned incident were benign, other incidents of similar nature have not been so. In 2004 a Russian virology lab scientist accidentally infected herself with Ebola, and died soon afterward. 

Need more examples? Smallpox was finally eradicated from the earth in 1977, except for a few specimens kept in laboratories under careful guard and supervision. In 1978 a British photographer, Janet Parker, who worked at the Birmingham Medical School, developed a nasty rash that was first diagnosed as chicken pox. The rash worsened, and Parker was hospitalized; she died weeks later of smallpox.

The building Parker worked in contained one of the research labs holding specimens of smallpox. How the smallpox escaped to infect Parker is not known.

Many similar cases — too many to mention, actually — take place daily around the world. Human error leads the list of causes, but mechanical errors, faulty protocols that are not recognized as such until after a crisis occurs, work to fill out the rest. At EntomoBiotics Inc., we don’t want to someday be a line item on that long list of laboratory mishaps.

With Human Safety at Stake, We Have No Choice…

We must minimize the risk of contamination by rodent-borne  pathogens to our lab personnel. To do this, once used E2M2C™ devices arrive at our laboratory, we require our lab workers to use strict sterile procedures while opening the bags, removing the rodent control products, and sanitizing the devices. The fewer steps needed to carry out this process, the less likely that cross-contamination will occur. By comparison, the more these materials are handled, the greater the risk of exposure to the pathogens they contain.

Yes, there are ways to reduce those risks to a practical zero, if followed precisely and consistently. Carefully controlled level IV biosafety laboratories — the kinds of laboratories that were permitted to store specimens of human H1N1 influenza virus, for example — employ bio-seal doors and cabinetry, autoclaves for lab equipment, and self-contained breathing apparatus integrated with bio-safe suits that prevent lab personnel from the slightest risk of contamination. Yet, as history has shown time and again, even these laboratories have spotty records of measuring up to their published standards.

Protecting our Lab Personnel, Our Clients, and the Public at Large, is Job # 1…

Scientific studies have shown that rats and mice carry 55+ diseases known to harm humans. The only way to avoid those risks is to institute strict sanitary practices that require handling the internal contents of each used E2M2C™ device as biohazard waste. Therefore, once rodent control products are removed from these devices they are immediately placed in a sealed bag for disposal according to CDC guidelines.

My concern here is not just the health and welfare of our lab personnel, but that of our clients and the general public. Our primary focus is and always has been on making sure that every E2M2C™ device not only protects everyone concerned from rodent infestations, but also from the pathogens those rodents and their ectoparasites are capable of carrying. We cannot do that job as well as we should by asking our lab personnel to handle the contents of returned devices any more than is needed to ensure those devices get fully sanitized.

In accordance with that goal, there is now no provision, whatsoever, for analyzing the rodent control products returned to our laboratory from the field. The temptation to do so is great, especially when a client vigorously insists on being privy to such information. For this reason, I have issued strict, non-negotiable instructions to my personnel against that practice. Any handling of that material beyond moving it from the station to a disposal bag carries too great a risk and will no longer be done. Our focus is on making sure each E2M2C™ device we bring in gets fully sanitized, inside and out, before being re-provisioned with fresh rodent control products and put back on the shelf. 

Still, E2M2C™ Assays Are What We Do, Every Day… 

Don’t despair… Assays are still on the table…

Assaying the result of the E2M2C™ program is still alive and well. We just conduct our assays without analyzing the actual consumption of rodent control products inside the E2M2C™ devices. The results are just as good as — even better than — those produced by measuring rodent consumption of rodent control products.

If you had been hearing rodent noises in your walls or ceilings, and you follow our instructions regarding the sequestration of food matter, those noises should cease within 3-7 days after we install the E2M2C™ program at your site. If you refuse to follow those instructions (some of our clients cannot imagine only feeding their pets at prescribed times during the day, then cleaning up within minutes after the pet has had its fill, denying rodents a source of food inside the home), we cannot solve your rodent infestation quickly, if at all.

If those noises persist despite your careful adherence to our food sequestration instructions, added adjustments need to be made. That can happen for several reasons, as when rodents in the attic are habituated to a dedicated food source off-site they make a bee-line to when leaving the attic to feed. When informed of the continuing noises, we conduct in-depth environmental assays to determine how the present placement needs to be adjusted. We’ve developed a protocol for such adjustments, one that is honed and refined on a regular basis.

Often all that is needed is to move one or more devices to other locations. In some cases we will need to add additional devices, up to the maximum stipulated by EPA guidelines.


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