The most important element of rodent management is exclusion. If a structure is fully protected, whether by sealing holes or fixing weather stripping, it often alleviates the need for catching, trapping or baiting. The industry’s most well-known rodentologist, Bobby Corrigan, knows that it’s this aspect of the battle against rodents that the layperson is less tuned in to, and more often negligent in considering. Corrigan offers the essential fundamentals of exclusion while providing important tips on how PMPs can fine-tune their exclusion skills.

CAPABLE ADVERSARY. “It’s amazing how intelligent rats are in figuring things out,” Corrigan says. “We’re learning more and more that these animals are clever explorers and once they lock on to food by smelling it, or they find a good harborage, they become highly skilled gymnasts.”

Corrigan says, that unlike many pests, rodents have the smarts to not only utilize tools, but also make decisions. This is due not only to their innate cleverness by design, but also by their biology and anatomy. But despite their skills as explorers, Corrigan is quick to remind technicians that rodents do indeed leave behind evidence that can help thorough PMPs locate weaknesses in a structure that provide rodents entry and clues to how those weaknesses are exploited. But one cannot expect the customer to see what a technician is trained to spot.

“I’m always stressing in my training that since we’re hired and we’re the professional we have to have vision that obviously the public does not have,” Corrigan says. He offers the example of a restaurant’s gnawed-away weather stripping, where rats have created a point of entry and how in most cases it will go unnoticed by building custodians. “The rats are gaining access there, going in, getting what they want and then going back to the sewer. We are trained to see it. They are not.”

This is not a problem exclusive to the United States, but all over the world, Corrigan explains. “Human beings are not able to grasp that if you keep them out in the first place, then you don’t have to catch, bait, trap and so forth later.”

TROUBLE SPOTS. Corrigan offers what he says are the four primary trouble areas rats and other rodents are expertly adept at exploiting. “First, any gaps at the ground level,” he says. Those are the areas most overlooked by the layman and amateur technicians. But a good PMP knows to look high as well as low, because, as Corrigan explains, rooftops are another common point of entry.

“Rats, of any species by the way, are adept at climbing buildings and getting up on roofs where they can come in from the top down, rather than from the ground up,” he says.

Doors, also at ground level, are often obvious culprits for allowing rodent entry, usually because they’ve either not been pest proofed, or they’re being left propped open by residents or employees.

The fourth possible trouble area covers a wide range of ways in which a structure’s integrity has been compromised. “Who knows how many points of penetration we have in commercial buildings or homes,” Corrigan says. “These can be any hole that goes right through a wall that’s not sealed correctly. Rodents are going to find that, and they’re going to take advantage of it and enter.”

Jody Gangloff-Kaufmann, NY State IPM Program

“Their muzzle comes to a long point, and tapers down,” Corrigan says. “And at the edge of that are very sensitive ‘nerve hairs’ if you will, that help them determine what they’re going to do — how to proceed.”

In addition to whiskers, Corrigan says rodents also have more nerve hairs growing out of the top of their heads behind their ears. They also help rodents make “decisions.” He’s quick to point out that this should not be dismissed as simple animal instinct. “We’ve learned that it’s more than instinct that tells them to decide when to go forth or not go forth into a hole, crevice or crack. We now know it’s something beyond instinct.”

So, the muzzle of a rat has more utility than that of a sensory area. It’s also, Corrigan explains, a tool to assist in choices for burrowing. “In the wild rodents use the muzzle to locate workable spaces beneath something heavy such as a rock,” he says. “They bring this same ability to everyday doors where they might be able to gain access beneath.

“In the wild rodents use the muzzle to create a space beneath something heavy such as a rock,” he says. “They bring this same ability to the city where there are structures they can get under. They try to burrow beneath heavy objects because of the protection they offer.”

But if a rodent can’t find a way under, to gain access to an area, they have other powerful tools, their incisors, that they use to find alternate entrances. Corrigan explains that a rodent’s incisors are powerful and can create access where access didn’t previously exist. For example, in a space around a structure where wood or other building material meets pavement, it’s impossible to burrow down beneath the structure to get in. In this case, the incisors can be used to gnaw away at the building material where it touches the ground, chewing to create a hole big enough to accommodate its passage.

And as Corrigan points out, those holes need not be big or even rat-sized, because of how the rodent’s anatomy allows it to squeeze its way into areas much smaller than its full body size.

“They have flexible tube-shaped bodies,” Corrigan says. “Their shape and flexibility allows them to squeeze through tight areas you wouldn’t expect. However, this is not to say that rats can “flatten” themselves out to squeeze under doors or other shallow horizontal spaces. “Because they’re flexible in the same way we are. Their backbones allow them to twist and turn and get the job done.

“The rule of thumb is, if the head can get through, the rat can get the rest of its body through.”

EVIDENCE OF INTRUSION. Once a PMP has trained his or her eye to identify a rat’s point of entry, there are other clues to be sniffed out, which can provide evidence of activity.

“Someone might see a hole and say, ‘How do you know that hole is still active? What if [the rats] built it there four years ago?’ Well, there are other signs that will point to whether or not the hole is in current use.

One, perhaps subtle, clue can be found in the area around the hole. If the hole is gnawed out of wood where it meets pavement, Corrigan advises to look closely at the color of the pavement around the hole as it compares to the rest of the pavement. “You might see a dark color around the hole — a dark, smoky-colored area on the pavement. That’s a sure sign the hole is active now,” he says.

MATT FRYE

It’s sebum, an oily grease excreted from the underside of a rodent, that accounts for the discoloration. “Once they’re pressed down against the ground to get into that hole, it rubs the sebum off of them and onto the ground,” Corrigan says, suggesting that a PMP might take a photo of the sebum-stained area to show the client. “Then you can say — look, you need our services.”

More intel can be gathered with a close look at the gnawed-away area. Corrigan suggests looking around the hole for the rodent’s incisor impressions to help you identify what kind of pest you’re dealing with. “Then, a pest professional should actually measure the width of the impressions. If they’re close to 4 millimeters across, it’s absolutely a rat. If 2 millimeters, it’s mice.”

WHY EXCLUSION? “Rodent proofing doors, and holes and gaps — is a job for professionals. But for us, once we agree to rodent-proof a door, we have to make sure we know what we’re doing,” Corrigan says.

Corrigan explains that not only is rodent exclusion important, it’s perhaps the most important aspect of controlling rodents, because whether it’s a big or small infestation, all it takes is one rat to bring much more unwanted things with it.

“Once they’re in, everybody is in,” Corrigan says. “They’re carrying fleas, ticks, lice and bacteria on them, so even though you may kill the rodent, anything of these things they brought in with them are still there. If a rodent is carrying a virus or a bacteria, of what logic is it to let them in your house or food plant or warehouse or restaurant, and to then try to control them after the fact?”

So even if a PMP manages to trap or poison the offending rodent, the question remains, how does one catch or contain any associated ectoparasites and pathogenic microbes that came in with the rodent?

Indoor infestations, for example, will still require careful cleanup, because even if the rodent is gone, droppings, urine, rodent hairs and decaying carcasses are still left behind. This, Corrigan explains, is why sanitation and pest control go hand in hand.

“Pest proofing is actually pest prevention and sanitation is pest control,” he says. “So if we keep things clean and clutter free it helps keep control.”

RIGHT & WRONG TOOLS. The tools of exclusion can be very effective if used properly, but as Corrigan explains you have to know what the right tools are before you get started. This might take some research on the part of the technician, but suffice to say that one key point to remember is that weather stripping and pest proofing are not the same thing.

“It’s amazing how people will just weather-proof doors as a way to keep out pests,” Corrigan says. “Weatherproofing materials are not made for this purpose, so they are completely inappropriate for this job.”

One commonly made mistake Corrigan cites is the use of heavy-duty vinyl weather stripping used as an exclusionary tool. A maintenance person is not trained to know these things, but Corrigan explains that simple vinyl used in even the strongest weather strips can still be easily chewed through by rodents. That’s why Corrigan suggests two specific types of rodent-proofing door seals: high-density nylon bristles and rubber-encased steel fabric (or RESF). “Nylon bristles are most effective for small infestations of mice,” Corrigan says. “But if it’s rats and mice, the rats will get through the bristles with no problem.”

Maintenance crews are not trained in pests. Even a heavy-duty strip of vinyl used as weather stripping can be chewed through by rodents. RESF sweeps, on the other hand, create several layers of challenges to the rodent which will effectively keep them out.

But even the best exclusionary tools are useless if not installed properly, Corrigan says. This means taking careful, accurate measurements of everything including any holes, entry points, door thresholds and piping hole gaps. A simple depth measurement of the opening in question can reveal whether the rodent being dealt with is a rat or mouse.

Foams are another material often misused by those who don’t know better. While they are ineffective for several reasons, they can be part of a bigger exclusionary strategy. Foam “plugs,” however, are terrible for exclusion when used alone because they’re not cleanable and their micro-crevices harbor germs, they’re porous, they degrade quickly, they’re easily gnawed by rodents and the expansion of foam blows out narrow board holes, widening them.

To use foam properly, Corrigan suggests this three-part strategy for holes in stone or cement walls of commercial accounts: “Put just a small amount of quality foam into the hole and then add a wad of stainless steel fabric so it’s enmeshed into the foam. Then finish with a dollop of quality sealant matched to that substrate.”

Pest proofing walls, holes, cracks and crevices requires that the PMP fill the hole. A heavy-duty sealant is what Corrigan recommends, though he is quick to point out that simple hardware-store caulk is not a sealant (even if it might say so on the label).

“Do your homework and know the difference,” he says.

The author is an Ohio-based freelance writer.

Mention birth control for rats in a conversation and you’re likely to evoke a chuckle or two. But it is that scientific development that brought Senestech Co-Founder and CEO Loretta Mayer to the attention of such world leaders as Theoretical Physicist Stephen Hawking, Former President Bill Clinton, India’s Prime Minister Narendra Modi and even the Dalai Lama. While most of us would be thrilled with the chance to meet, let alone have a dialogue, with such historical figures, the greater gratification for Mayer is the reasons for and outcomes of such discussion: the long-term reduction of rodents in the fight against food insecurity, infrastructure damage and disease transmission.

From its origination as a way to study heart disease in women through menopausal mice to its applications in Asia to reduce the rat populations in rice farms, Mayer and co-founder Dr. Cheryl Dyer have brought the fertility control concept through a complex evolution to attain EPA registration for the use of the active ingredient in rodent management in the U.S.

It hasn’t been an easy road, nor one that followed a preset plan. “I think one of our successes was that we didn’t know what we didn’t know,” Mayer said. That success amazes even her. “This little company...how did we make it?” she asked. “We were two dreamers with no money but a desire to make an impact.”

THE MAKING OF A SCIENTIST. It all started when Mayer’s friend, Gladys Johnston, whom she saw as mentor and mother-figure, passed from a massive heart attack. Heartbroken, she went to scientist Dr. Linda Curtis asking why her friend died. The response: If she were male, we’d know exactly what happened, but we don’t know much about women and heart disease. “We need to change that,” Mayer said, saddened and perplexed by the lack of knowledge. “Make me a scientist.”

She made a deal with Curtis: “I will work for you for 30 days. I will do anything. At the end of the 30 days, you’ll honestly look me in the eye and tell me if I can become a scientific researcher to find out about heart disease in women.” Curtis agreed and assigned her to work with Dyer. It was to be an auspicious introduction.

It wasn’t the first time Mayer would follow her passion to change the world, and it wouldn’t be her last. Although she’d always been drawn to science, Mayer attained a B.A. in sociology from the University of California, San Diego in 1971, “having been very engaged in the activism of the ’60s,” primarily combating social inequality. But, she ended up in a clerical position in a financial company because, she said earnestly, “I was just stunned that no one wanted to pay me to change the world.”

But through a series of “You seem smart, can you learn to...” opportunities, Mayer got licensed in and/or learned the world of securities, real estate, insurance, construction and property management — through which she ran a highly successful real estate development company.

It was precisely because none of this still satisfied her desire to change the world that Mayer took on the 30-day challenge — which she passed with distinction. And when she did, she sold her real estate development business — giving all its employees a generous severance because, she said, “They shouldn’t have to pay for my decisions.” Then, moving herself and her 13-year-old daughter to a smaller home, she released her cook, housekeeper and chauffeur; sold off a majority of their possessions at a swap meet; and went back to school at the age of 41.

It was while working toward her masters and doctorate in biology/biological sciences that Mayer began to work with Toxicologist Dr. Pat Hoyer, who was studying a compound “that caused the rapid natural acceleration of loss of eggs in the ovaries.” Although the toxicologist saw no good use for the compound, Mayer told her, “That may be your trash, but it’s my treasure, because if I could make a transgenic mouse menopausal, and it still had its ovaries, we could study women’s heart disease, osteoporosis and even ovarian cancer in a menopausal model.”

While Mayer’s ultimate goal was such study, she was continuing to publish papers about the compound’s effects on mice, i.e., infertility or birth control. And that set the wheels in motion for two career-altering phone calls. The first was from a veterinarian in New Mexico, Dr. Clint Balok, who saw its potential for reducing the need for euthanasia of animals, telling Mayer that if she could do for dogs what she did for mice, he could quit killing animals; if we could stop their breeding, we could stop the overpopulation.

“That struck a cord in me,” Mayer said. “And I woke up in a bunkhouse in New Mexico with 18 dogs I had adopted.” The compound worked...and she ended up bringing all 18 dogs home with her.

The second call was from an investigator in Australia, Dr. Lyn Hinds, who wanted to speak with her about the menopausal mouse model for use in Asia where the rice field rat was destroying up to 30% of the crop of the small farmers. Mayer was told that stopping reproduction in 50% of the rats could reduce destruction by 80% and a 5.0% drop in the rat population could feed 400 million people. “That was compelling,” she said. “I did a lot of reading and the literature convinced me...so then I woke up in a rice field in Asia.”

COMING TO AMERICA. With other similar applications beginning to be requested, Mayer realized it was time to form a business. Having continued to work with Dyer since her 30-day test, the two formed Senestech in 2004 — “with two Ph.D.s; a cell phone; and a business neighbor, Jim Dawson, who would sign the documents of incorporation,” Mayer said. “I didn’t want to go back into business, but as any scientist will tell you, if you can’t take your ideas from your bench to the marketplace, you won’t have an impact; you’ll just have a lot of great publications.”

It then became clear that the technology needed to be developed into a product that would be attractive to rodents and affordable for use, she said. Thus, the invention of ContraPest: a non-lethal, rodent fertility control product that targets both female and male Norway and roof rats. Although Senestech was doing a lot of work in Indonesia, Phillipines, and Laos, they had not applied for EPA registration for use in the U.S. primarily because of the time and money that would take.

Then an EPA representative got wind of the product, saw its potential, and asked them to come to Washington, D.C., to present it to an EPA team. It turned out to be an unusual meeting. Not only did EPA approve the application based on Senestech’s two years of preparation, but registration was attained in less than a year.

The two women continued to attain such unique support from influential government leaders in various areas — with an NIH grant funded for the business in its headquarters city of Flagstaff, Ariz., because it would add jobs, and a support letter from the New York City Transit Authority for an experimental use permit in the subways because, thus far, nothing that had been tried previously had been sustainable. For this use, the product was manufactured in liquid formulation because of rats’ need for water and the dry environment typically found in subway systems. “The bait is fatty and sweet and just about everything a rat could want,” Mayer said. “And because it doesn’t harm them, there is no bait shyness.” Within 12 weeks, the rat population had been reduced by 43%, she said.

BALANCING THE BATTLE. “Pest management professionals have been fighting an uphill battle for hundreds of years to solve rodent problems,” Mayer said. “We learned in Asia that they will outbreed any type of lethal approach. If you use a lethal approach, the ones who survive are the ones who are resistant or savvy, and they continue to breed.” That doesn’t mean, however, that rodenticides shouldn’t be used, she added. Fertility control is not a silver bullet, it is a tool and needs to be used in conjunction with a full program. It can be most useful as a stand-alone product in areas such as parks and zoos where lethal means are a concern, whereas more sensitive sites such as food plants that have zero tolerance for pests and may require faster, more complete eradication, fertility control works best as a complement to existing IPM protocols, she explained.

“When animals and humans collide, if the animals are destructive in any way to the human population, they become pests,” Mayer said. “In this pest management world, we’re dealing with the intersection of people and animals. There are so many approaches, and the success will come from all of us working together. People are passionate about their wildlife. I get that. But it’s like stepping over and looking at it from this side: having a rat carrying Leptospirosis in a childcare center is unacceptable. We are still struggling with management, but management will come from balance; it won’t come from eradicating anything.”

With Senestech’s mission to ease the issues caused by the interaction of humans and animals by reducing the “pest” populations, Mayer sees herself as the link between the diverse worlds and objectives of pest managers and wildlife and animal welfare groups. “There is a beautiful blend and harmony here that I’d really like to be a voice for,” she said.

CONTINUING STUDIES. A scientist at heart, Mayer’s successes haven’t stopped her studies on rodents; in fact, additional research was integrated into the subway efforts. By using a special dye in the bait which fluoresces in the rat’s whiskers, they were able to tell which rats ate the bait, for how long, and how many times they returned to consume additional bait. Mayer then worked with an animal sanctuary, where the product is ideal because of its non-lethality, she said. From compiled GPS tracking of the rodent feeding laid over standard rat home ranges, she was able to show where the rats were traveling.

Mayer has continued to conduct field inquiries about experimental projects outside the U.S. on fertility control of other animals, such as squirrels in Great Britain; voles in Germany; felines, marsupials and wallabies in Australia; and brushtail possum in New Zealand. And research also has been conducted within the U.S. on feral pigs with Texas A&M. “As our company grows, we first had to grow in the most challenging species we could face — which was the rat. And I’m feeling pretty good about that,” Mayer said.

With Senestech a publicly traded company of 40 employees, Mayer knows it’s all about people. “If you have the right people with you and around you, you have their support, you lend your passion to them and it begins a movement. Then you reach that tipping point; you take a deep cleansing breath and step into that forward current together. We’re all in the boat: the guy on the right has the oar and the gal over here has the helm, and we’re making it.

“That’s what it’s all about; it’s the people,” she said. And it is about the diversity of those people — diversity of gender, age and culture, Mayer said. Although all are equal, all are not the same and each brings his or her own traits and skills that are “hard-wired biologically,” she said. Mayer has had people say that Senestech is a woman-dominated company. “I don’t really believe that’s true,” she said. “We have a lot of females, but what you don’t understand is the complete and total success matrix of our males and females working together. You need those males with the fight or flight response to stress, and you need those females with the tend and befriend mentality. And when you put those together you have the secret for success.”

The same is true with the balance that is brought through the diversity of age and culture, she said. “You have to have that wonderful, wonderful diversity.”

Mayer’s father always told her: “You can do anything you really set your mind to.” Having set her mind on changing the world, it seems that Mayer is well on her way to doing just that.

As Stephen Hawking said, “If Loretta is right, it’s going the change how we do things forever.” Nothing could be closer to Mayer’s heart.

The author is editor of QA magazine, a sister publication of PCT. Email her at llupo@gie.net.

“That which can be foreseen can be prevented.” — Will Mayo, 1910

 

The purpose of this article is to provide an important research update addressing the significance of city mice and rats and everyday public health. As PMPs likely already know, public health updates are important for the pest management industry. They not only help us better serve our residential and commercial clients (e.g., schools, restaurants, office buildings), but even for our own lives, homes and families.

VIRUS HUNTERS. In New York City, the well-respected Center for Infection and Immunity is located at Columbia University’s School of Public Health. The scientists at this center have been studying the microbial pathogens (e.g., viruses, bacteria) associated with various insect and animal vectors (e.g., mosquitoes, rodents, ticks, etc.) for years.

This update also provides important tips for safely working with rodents on your everyday accounts. Moreover, these research findings should serve to emphasize why the integrated portion of Integrated Pest Management (IPM) must continue to be strongly emphasized in urban rodent control.

One group of these scientists is led by Dr. Ian Lipkin, the virus hunter internationally recognized for his work with West Nile virus and SARS. Dr. Lipkin served as the science consultant for the film Contagion — a film that was acclaimed for its scientific accuracy.

Beginning in 2012, Dr. Lipkin’s teams began live-capturing and analyzing everyday city rats and mice from New York. The goal was to study which viruses and bacteria these rodents were carrying, and whether or not they might pose public health threats. Columbia published their important research findings of city rats (Rattus norvegicus) in 2014. (See references on page 46.)

The more recent rodent research update (and addressed here) discusses Columbia’s second rodent research project, which was conducted similarly to the rat study, except it focused only on wild house mice (Mus domesticus). The research findings were published in two separate journal papers earlier this year and received quite a bit of attention from the global press (which no doubt, many of our clients read online and may have had follow-up questions for you out in the field). The following is an overview of the research findings.

CITY MICE & GERMS. The city mouse project was led by Simon Williams, a research scientist with Ian Lipkin’s lab at Columbia. Simon was joined by a team of virologists, microbiologists, epidemiologists and rodentologists.

The mouse team live-trapped 416 wild house mice from various residential and multi-functional buildings throughout greater New York. By employing a range of sophisticated laboratory techniques, the droppings, urine and the mice themselves were analyzed, allowing Williams’ team to isolate and identify the bacteria and viruses found on and within the mice.

DANGEROUS FINDINGS. Importantly, the collected house mice were found to be carrying several of the bacteria responsible for human gastroenteritis (inflammation of the stomach and intestines, typically resulting from bacterial toxins or viral infection).

Five bacterial pathogens and one protozoan were discovered in the wild house mice with significant frequency:

1. Salmonella (different strains)
2. Escherichia coli
3. Clostridium difficile
4. Shigella
5. Leptospiria spp.
6. Toxoplasma gondii (protozoan)

Depending on the acquired infection level and the specific bacterial pathogen, should a person ingest (directly or indirectly via contact or inhalation), the resultant sicknesses ranges from mild to life-threatening. Salmonella bacteria, for example, is a leading cause of bacterial food poisoning in the United States with 1.4 million reported cases annually along with 15,000 hospitalizations and 400 deaths. And if we consider the impact of all foodborne pathogens, the Centers for Disease Control and Prevention in 2010 reported a staggering 76 million cases of foodborne illness and between 3,000-5,000 associated deaths occurring every year in the United States.

Among the millions of less severe cases of foodborne illness infections (and if you are reading this, no doubt you have “been there, done that”), most result in diarrhea, fever and stomach cramps with accompanying and sometimes severe vomiting one or two days after contact or somehow ingesting the bacteria or viruses from fecal or other contact from rodents or other pests (flies, cockroaches) or animals (see Figures 2 and 3).

Toxoplasma gondii is a protozoan parasite that causes toxoplasmosis, of which the cat is the definitive host. Cats become infected by killing and eating house mice infected with T. gondii. When the parasite gains a foothold around mouse-infested homes and apartment complexes (via cat feces accumulating in basements, crawlspaces, unkempt apartments, etc.), the house mouse serves as an intermediate host contributing to the parasite’s persistence and propagation. If pregnant women contact infected cat feces, they can become infected, resulting in spontaneous abortions or various fetal abnormalities, such as lifelong retinal damage causing partial or complete blindness in one or both eyes.

The leptospira bacteria found in the NYC mice (and rats) are probably the most widespread and most prevalent of all zoonotic diseases (i.e., transferable from lower animals to man). The leptospirosis bacteria can be transmitted to people via the urine from rodent pests around buildings. This happens via skin contact with leptospirosis-contaminated water, moist soil and vegetation, or sometimes via the direct ingestion of food contaminated by infected rodents.

Symptoms of leptospirosis often closely mimic the common flu: fevers, headaches, diarrhea, chills and vomiting. As such, many cases are too casually dismissed by both the patients and their physicians as “the flu.” In severe cases, however, this bacteria can be deadly as it can cause severe kidney damage, jaundice and hemorrhaging. Just last year (2017) in New York City, rodent-transmitted leptospirosis killed one and hospitalized others in the Bronx. Because leptospirosis is prevalent among rodents in American cities containing high populations of rats and mice, perhaps health departments should undertake more preventive programs with appropriate serology and analyses of local rat populations. (See the comments of Lieberman.)

It should be noted that the discovery of these particular germs with the NYC mice isn’t revolutionary. During the past several decades, other researchers have recorded rodents carrying various microbial pathogens. What is significant is this was the first time a random sample of just a tiny portion of the wild house mice of America’s most highly dense and populated city has been profiled — which begs the question: “What might be the profile of any of the other millions of mice not sampled?”

There was an additional interesting and important finding in the study. Columbia also discovered within the NYC mice the evidence of genes widely distributed that can bring about antimicrobial resistance (AMR) to several of our most common antibiotics including the fluoroquinolones and -lactam compounds. Notably, these particular antibiotics are, in fact, among the most commonly used drugs to combat the bacterial gastrointestinal infections caused by the pathogens discovered in the wild mice of this study.

For example, one of the fluoroquinolone antibiotics is ciprofloxacin (trade name: Cipro). This drug is used worldwide for the treatment of gastroenteritis. And, the -lactam drugs include the universally known penicillin derivatives. For many years, more than half of all commercially available antibiotics in use were of the -lactam compounds.

With the Columbia study then, it is yet another example of the axiom “the deeper we look, the more we find.” Finding the AMR association in everyday house mice certainly opens up the door for additional questions regarding one of our most pressing worries — the threat of continual increase of antibiotic resistance.

NOVEL VIRUSES. Columbia’s second study on house mice (also published in the journal Molecular Biology), investigated the viruses present in mouse droppings. Interestingly, 36 viruses, including six new viruses, were identified. None of the viruses were found to be varieties that cause human illness; this was different from what was found in the bacteria study.

This is not to say the wild mouse viruses were cleared of all guilt. The study did identify genetic sequences matching important viruses that infect insects, dogs, chickens and pigs, findings which will certainly be of interest to veterinarians and livestock producers everywhere (considering how prevalent mouse infestations are around livestock, animal hospitals, zoological parks and so on).

Nevertheless, the lack of human-pathogenic viruses — at least in the sample of mice collected in this study — is a bit of a relief compared to what we’ve been alerted to with mouse viruses during the past 30 years (e.g., hantavirus and deer mice, LCMV, etc.).

 

NO GUARANTEED TRANSMISSION. It is important to keep in mind, not only for this study, but for any research addressing pest-species vectors, that just because animals are found to be harboring germs, it doesn’t guarantee those germs will be transmitted to other animals around them. Such is the case with this house mouse study as well. More research is needed to measure, if possible, the likelihood of transmission of microbial pathogens found on mice and rats, or even cockroaches and flies, for that matter, under typical everyday conditions.

Still, it’s sobering that in only the space of a period at the end of a sentence several million viruses can fit. And, only one mouse in a restaurant can produce upwards of 125 fecal pellets and upwards of thousands of microdroplets of urine in 24 hours (see Figure 3).

What’s more, we know mice constantly dart about in thousands of “spots” throughout the rooms where they are active day-in and day-out and that they tend to investigate many of the everyday objects they encounter during those forays. So, it seems an obvious likelihood that sooner or later an infected dropping or micro-droplet of urine will find its way into “our world.”

(Photo: Bobby Corrigan)

One example of this would be the all-too-common mouse infestations that occur in the ceilings above the kitchens in our commercial accounts (e.g., restaurants, bakeries, delis, grocery convenience stores, etc.). For these infestations, there is a decent possibility of pieces and parts of feces, hair, urine fragments and so on routinely falling down (partly by the daily vibrations that occur from all the moving of objects and activity below busy commercial ceilings) onto foods, food boxes, preparation areas, utensils, plates, pots and pans and the like. Similarly, droppings and urine can be deposited within food containers stored within the mouse-attracting dark, quiet drawers and closets of common household pantries of residences everywhere (see Figure 2).

The bottom line: transmission of bacteria and viruses from interior mice can happen at any time and in any number of ways. This also includes when we are actually trying to clean up the presence of germs and dirt via sweeping and vacuuming — which can then render microbes airborne and inhaled by those doing the cleaning.

WHAT’S IN YOUR WALLET? Perhaps you are thinking, “Well, the rats and mice collected in these studies were from New York City, a very crowded, old seaport city with more than 900,000 buildings and lots and lots of garbage, litter and the like. It doesn’t mean the rodents in my city, town or area are carrying the same pathogens.” Well, maybe. But until a city rodent/pathogen profile is conducted in your city, the question truly is, “What’s in your wallet?” Maybe it’s less? But maybe it’s more.

This then leads us back to the Will Mayo quote at the beginning of this article about being preventive (in part, via effective, well-designed and well-implemented pest management programs at the ground level). Because in all cities around the entire globe, the fact of the matter is millions of cases of unexplained febrile illnesses year after year are not actually diagnosed.

When it comes to being preventive around any city where mice and rat infestations occur, Jay M. Lieberman, M.D., an infectious diseases specialist and former professor of clinical pediatrics at the University of California, Irvine, suggested in an important 2009 publication salient advice for all: namely, that when any ill person is brought in for medical attention with an unexplained fever-related (i.e., febrile) illness or infectious disease, clinicians should routinely ask about any potential exposures to animal pests such as mice and rats that have been active around the domicile or workplace.

TAKE-AWAY TIPS. Rodent control is among our industry’s highest revenue-generating services, as well as one of our primary identities as to why we truly do help protect the health and lives of humans. So how can we use this important research update in what we do and what we offer in our services, not to mention in our own daily work?

Here are some tips:

• The Columbia research further substantiates the importance of the basic tenets of exclusion and sanitation within the urban IPM model. If rodents can’t get into the buildings in which we eat, sleep and work in the first place, they can’t deposit fecal matter of any sort containing pathogens and/or the genes for facilitating anti-biotic resistance that we may later contact, ingest or inhale.

• Ensuring rodent-proof doors, sealed holes and detailed/cleaned floors in shadowy, hard-to-reach spots (i.e., the favorites of house mice) is not, as the saying goes, rocket science. Updates in the public health risks of rodent pests can help our clients be aware of the importance of the essential partnership in any IPM program between them and us. Company fact sheets, website blogs and simple handouts with highlighted points recapping such research can go a long way in your role in promoting public health to schools, homes, apartment and office buildings, restaurants and so on.
• Any client with a current rodent infestation and/or who has called upon you to provide the service to eliminate such rodent infestations should be reminded as to the importance of personal hygiene (e.g., frequent washing of hands) — especially until the rodent infestation is corrected.
• Services to address rodent infestations must be sold with an attitude of achieving high control on an ASAP basis. Inexpensive services can hardly input the up-front labor necessary to get the population eliminated fast. (Consider all the fecal material that can be laid down by a few mice in just a few days.)
• Rodents in our commercial accounts tend to favor nesting and reproducing and being most active in those structural areas that are often hard-to-reach (and thus often prone to being skipped over during service visits). Employing any of the electronic remote sensors now available on the market serve as important food safety and public health monitors in this regard.
• Cleaning up any excrement and associated rodent filth is the client’s responsibility. Clients should clean and disinfect all areas in which rodents have been traveling and/or have left fecal material (advise clients to refer to the www.cdc.gov for proper methods of disinfecting small and large amounts of animal excrement).
• All on-the-job pest professionals must always wear issued PPE (gloves, respirators when inside enclosed spaces) while performing inspections, and/or laying down indoor rodent control equipment within infested areas.
• Always wash any coveralls or discard any Tyvek-style suits in the proper donning and doffing procedures after using them in crawlspaces, attics or other areas/surfaces where rodent infestations occurred. (Check the cdc.gov site for donning and doffing in these scenarios.)
• Even after wearing your disposable gloves during rodent control work, wash your hands after removing the gloves each and every time.
• Never, ever, clean out rodent-visited exterior bait stations or traps by sweeping the station’s contents (feces, dirt, hairs, etc.) onto any client’s property.
• To dispose of dead rodents found on the job (including contaminated glue traps) always double-bag and remove the contents from the premises and discard in an appropriate trash receptacle.

SUMMARY. Perhaps the most succinct way to summarize this important Columbia University research would be to consider two things. First, what if the mice collected from this study targeted only the mice of restaurants, or schools, or office buildings? Would less, or more pathogens have been found?

(Photo: Bobby Corrigan)

And second, I’d like to repeat the answer to a question I had posed to the famous food microbiologist Dr. Michael Doyle, of the University of Georgia, at a food safety symposium awhile back: “Would you, Dr. Doyle, eat in a restaurant if you knew it had only one mouse positive for Salmonella enteriditus hiding somewhere in the kitchen?

”Dr. Doyle’s answer: “I would not. Would you?”

The author is an urban rodentologist with RMC Pest Management Consulting, Briarcliff Manor, N.Y.

References (Free via open access [OA])

Firth C., Bhat M., Firth M.A., Williams S.H., Frye M.J., Simmonds P., Conte J.M., Ng J., Garcia J., Bhuva N.P., Lee B., Che X., Quan P-L, Lipkin WI. 2014. Detection of zoonotic pathogens and characterization of novel viruses carried by commensal Rattus norvegicus in New York City. mBio 5(5):e01933-14. doi:10.1128/mBio.01933-14.

Simon H. Williams, Xiaoyu Che, Ashley Pawulick, Cheng Guo, Bohyun Lee, Dorothy Muller, Anne-Catrin Uhlemann, Franklin D. Lowy, Robert M. Corrigan, W. Ian Lipkin. New York City house mice (Mus musculus) as potential reservoirs for pathogenic bacteria and antimicrobial resistance determinants. mBio, 2018; 9 (2): e00624-18 DOI: 10.1128/mBio.00624-18

Simon H. Williams, Xiaoyu Che, Joel A. Garcia, John D. Klena, Bohyun Lee, Dorothy Muller, Werner Ulrich, Robert M. Corrigan, Stuart T. Nichol, Kormal Jain, W. Ian Lipkin. 2018. Viral diversity of house mice in New York City. mBio 9:e01354-17doi: 10.1128/mBio.01354-1717 April 2018 mBio vol. 9 no. 2 e01354-17

Lieberman, J.M. 2009. North American Zoonoses. Pediatr Ann. 2009 Apr:38(4):193-8

By Dan Moreland

With bed bugs becoming an increasingly important economic driver for PMPs in many parts of the world, it should come as no surprise that the NPMA Global Bed Bug Summit, sponsored by BedBug Central, drew a record crowd of attendees to the Mile-High City in November.

It’s the third time the biennial event has been held in Denver, and despite the familiar feel of the venue, the most recent edition of the conference and trade show had a uniquely distinct vibe, in part because Multi-Family Housing and Business Tracks were added to the program, complementing the always-strong technical sessions.

When all was said and done, more than 575 industry professionals and 55 vendors attended the three day-event, including a growing contingent of representatives from the multi-family housing market.

“This past year BedBug Central has been working closely with the affordable housing market,” observed Phil Cooper, founder of the Global Bed Bug Summit. “We’ve identified that it’s a market with several different associations representing different groups within the market, but these groups don’t seem to interface with each other too often. We aim to establish a connective tissue that assists with helping all the groups with information on bed bugs, pest control and many other topics pertinent to the affordable housing industry.”

In an attempt to expand its market footprint and gain a better understanding of the multi-family sector, BedBug Central has built a 3,000-person database to strengthen its relationship with this important, yet traditionally underserved market. “We think getting to know the wants and needs of the multi-family housing market will allow the pest management industry to serve this segment more effectively in the future, which is our ultimate goal,” he says.

Phil Cooper (left), founder of the Global Bed Bug Summit, and Dominique Stumpf, CEO of the National Pest Management Association.

ONGOING EVOLUTION. Another goal of the event is to continue to invest in the Global Bed Bug Summit’s core audience, PMPs charged with controlling these ubiquitous pests. Rob DiJoseph, president of BedBug Central, has been pleased with the evolution of the conference, which has grown from a largely technical meeting to an educational forum designed to address all facets of the marketplace (i.e., sales, marketing, regulatory, community outreach, etc.).

“I think the tone of the event has changed,” he said. “Since its inception in 2010, the Global Bed Bug Summit has matured and made great strides, addressing all facets of the bed bug market. We’re doing more from a business perspective now, which is good, without diminishing what has always been the core strength of the Summit, which is the ongoing research that is being conducted around the globe by leading industry educators, which have long supported this event.”

“What makes this event so great is its singular focus on bed bugs,” added NPMA CEO Dominique Stumpf. “It allows us to examine the bed bug market from all angles, which we hope will result in its continued expansion. I was particularly pleased to see that 30 to 40 percent of those in attendance were first-time attendees, which bodes well for the market.”

“I think we’ve done a good job of adapting to the changes that have occurred in the industry since the event’s inception,” DiJoseph added. “Like business, you can’t rest on your past accomplishments; you must constantly evolve to ensure the content remains fresh and relevant, and I think we’ve done that with the Global Bed Bug Summit.”

DiJoseph noted that another development has been the creation of a recurring revenue model for bed bug services, a trend embraced by Joseph Latino of Allergy Technologies, one of the corporate sponsors of the Global Bed Bug Summit, who has been a longtime proponent of such an approach to the business.

As it has incorporated various monitoring and control programs into its service offerings, “the industry has done a good job of beginning to generate recurring revenue with its bed bug services,” DiJoseph observed.

“I think there is a sea change occurring in the industry when it comes to providing preventive pest control services,” Latino added. “The industry has had year-after-year growth in the absence of a recurring revenue business model, so imagine what we could do as an industry if we successfully adopted a more robust recurring revenue model in the future?”

OTHER HIGHLIGHTS. Bookending the three-day event was a meeting of the Colorado Pest Control Association, which reported record attendance for its Winter Conference, and a meeting of the State Association officials, which was held the day following the close of the Global Bed Bug Summit. “Combining these events helped drive attendance to the Summit and served everyone well,” DiJoseph said.

Educational sessions presented at the conference featured a “Who’s Who” of the global bed bug research community, including such well-known names as Dr. Dini Miller, Virginia Tech; Dr. Stephen Doggett, Westmead Hospital; Dr. Karen Vail, University of Tennessee; Dr. Alvaro Romero, New Mexico State University; Dr. Chow-Yang Lee, Universiti Sains Malaysia; Dr. Susan Jones, The Ohio State University; Dr. Nina Jackson, Penn State University; Dr. Changlu Wang, Rutgers University; and Dr. Zachary DeVries, North Carolina State University.

Prominent PMPs presenting during the well-attended Business Track sessions included Adam Vannest, Northwest Exterminating, Marietta, Ga.; Keith Robinson, ABC Home & Commercial Services, Dallas, Texas; Travis Aggson, American Pest Management, Manhattan, Kan.; Jeff White, BedBug Central, Lawrenceville, N.J.; Dr. Judy Black, Rollins Inc., Atlanta, Ga.; Jeff King, The Pest Rangers, Wilkes-Barre, Pa.; Dr. Richard Cooper, Terminix, New Brunswick, N.J.; Ross Treleven, Sprague Pest Solutions, Seattle, Wash.; Jay Everitt, Rottler Pest & Lawn Solutions, St. Louis, Mo.; Tom Jarzynka, Massey Services, Orlando, Fla.; Adam Witt, Witt Pest Management, Pittsburgh, Pa.; and Brandon Gile, Platinum Pest Solutions, Chicago, Ill.

Other industry stakeholders appearing on the program included Dr. Brittany Campbell, staff entomologist, National Pest Management Association; Amanda Tongue, account manager, Vault Communications; Dr. Marcia Anderson, environmental specialist, Environmental Protection Agency; and Susannah Reese, program coordinator, Northeastern IPM Center.

“The educational needs of the bed bug market continue to evolve and we worked closely with BedBug Central to address those needs when putting together the most comprehensive educational program in the history of the event,” observed Stumpf. “We have a very collaborative relationship with BedBug Central and we began working on the program nine months in advance of the program. Jeff White of BedBug Central and our own Jim Fredericks did a great job putting together this year’s program.”

In addition to BedBug Central, other corporate sponsors of the three-day event included Allergy Technologies, a platinum sponsor; MGK, a gold sponsor; and AMVAC, ConidioTec, EcoRaider and Heat Assault, all silver sponsors.

The Global Bed Bug Summit has always had a “relaxed vibe,” DiJoseph said. “It doesn’t take itself too seriously. We devote a lot of time and energy to creating a high-quality educational program and trade show, but we also like to have some fun,” as evidenced by a Beer Tasting event in EXPO Central and a Night Out with the Experts at the end of the day on the second day of the event. “We like to think of the Global Bed Bug Summit as being formally informal,” DiJoseph says with a laugh.

Plans are already in the works for the 2020 edition of the Global Bed Bug Summit, which will be the 10th anniversary of the event. The event will be held Dec. 1-3 at the Sheraton Denver Downtown. In-depth coverage of individual educational sessions presented at the Global Bed Bug Summit will appear throughout the year in PCT magazine.

The author is publisher of PCT magazine.