Chagas disease, caused by infection with a parasite called Trypanosoma cruzi (T. cruzi), causes chronic heart disease in about one- third of those infected. Over the past 40 years, Chagas disease has spread to areas where it had not traditionally been seen, including the United States, according to a new American Heart Association scientific statement published in the American Heart Association journal Circulation.
T. cruzi infection occurs when feces from the infected blood-sucking insect triatomine enters the skin through the bite site or in the eye. Triatomine insects are found in Central and South America and in the Southern United States. The disease also can be passed through contaminated food or drink, from pregnant mothers to their babies, and through blood transfusions and organ transplants.
The health risks of Chagas disease are well-known in Latin America, where most cases are found, including in Brazil, Argentina, Bolivia, Paraguay, Mexico and El Salvador. However, doctors outside of Latin America are largely unaware of the infection and its connection to heart disease. Countries where infected individuals have been diagnosed include the United States with an estimated 300,000 cases.
“This statement aims to increase global awareness among physicians who manage patients with Chagas disease outside of traditionally endemic environments,” said Maria Carmo Pereira Nunes, M.D., Ph.D., co-chair of the committee that produced the statement.
Although 60 to 70 percent of people infected with T. cruzi never develop any symptoms, those who do can develop heart disease, including heart failure, stroke, life-threatening heart rhythm abnormalities and cardiac arrest. In the Americas, Chagas disease is responsible for more than seven times as many disability-adjusted life-years lost as malaria. However, if caught early, an infection can be cured with medications that have a 60 to 90 percent success rate, depending on when in the course of infection the patient is treated.
“Early detection of Chagas disease is critical, allowing prompt initiation of therapy when the evidence for cure is strong,” said statement co-author Caryn Bern, M.D., M.P.H., professor of epidemiology and biostatistics at the University of California in San Francisco. Source: American Heart Association
What do Consumers Think?
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Numbers don’t lie. Research from PPMA shows what consumers’ pest-related health fears are, as well as what they think of the pest management industry.
Now that we know a bit about which insects are in peoples’ homes and how the public thinks and feels about those pests, PCT wanted to “dive deep” into what actions consumers take when it comes to pest management in their home.
In 2016, the Professional Pest Management Alliance (PPMA) commissioned a third-party research firm to conduct a survey of homeowners to learn more about professional pest control usage and public perception of the industry. A total of 2,027 interviews were conducted among adults, 25 and older, who live in the United States and are homeowners with a household income of $60,000 or more.
PPMA’s research confirms what was reviewed previously in this month’s cover story: People just don’t like insects.
The No. 1 reason consumers elect to have a contract or regular service with a pest control company is because doing so “best protects my home and/or my family,” the reason given by 70 percent of respondents. But almost half — 45 percent — said the reason they hire a PMP is because they “cannot tolerate pests in and around my home.”
One-third of homeowners are extremely concerned about pests damaging their home and property while three in ten are extremely concerned about pests causing illness to them and/or their family.
Digging deeper, those ages 25-44 are more concerned than those ages 45-64 and 65 and older about pests damaging their home and property (mean = 8.62 vs. 7.37 and 6.59), pests causing illness (mean = 8.54 vs. 6.45 and 5.39), insect bites and stings (mean = 8.32 vs. 6.32 and 5.73) and the stigma of having a dirty home (mean = 8.20 vs. 5.54 and 4.63).
Consumers identified their top five pest control concerns as ants (44 percent), spiders (39 percent), mosquitoes (34 percent), rodents (34 percent) and cockroaches (31 percent). Perhaps surprisingly, termites and bed bugs didn’t make the top five.
When asked which pest they were most concerned about as far as their family’s health, more than two in five homeowners said mosquitoes and rodents are the biggest threats, followed by cockroaches, ticks and bed bugs.
But when asked which was the biggest threat — selecting only one — rodents and mosquitoes tied at 21 percent and bed bugs dropped to 6 percent, below cockroaches, ticks, termites, stinging insects, and tying with spiders.
Almost three in five homeowners were concerned about Zika (59 percent) and Lyme disease (58 percent), while more than half were concerned about allergic reactions to stings and West Nile virus.
TO LEARN MORE
The full PPMA survey results are available exclusively to all PPMA Guardians and investors who contribute more than $1,000 annually, as well as Mainframe subscribers on PPMAMainframe.org. Non-subscribers or firms that are not investing in PPMA at the minimum level can purchase a copy of the survey results for $1,000. Contact Cindy Mannes for more information at email@example.com.
Scorpions Outdo Spiders as Scariest
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Although spider fear is one of the most common and well-studied phobias, a UCR-led study shows people are more afraid of scorpions.
“I’d rather scoop maggots off a corpse than deal with a spider.”
Those are some of the typical responses Rick Vetter hears when he tells people about his work as an arachnologist at the University of California, Riverside (UCR).
“It doesn’t matter if I say they’re beneficial, many people just want them dead,” said Vetter, a retired research associate who spent 32 years in UCR’s entomology department. “Even some of the entomologists I’ve worked with are incredibly afraid of spiders.”
Spiders and snakes reign supreme in the world of animal phobias, but the evolutionary reason for spider fear isn’t well understood. Some psychologists believe it has an innate foundation, since humans may be genetically programmed to fear animals that can cause them harm.
Such visceral reactions to spiders have always intrigued Vetter, who said most of the long-legged arthropods are “easily squishable” and few are harmful to humans. Even those that bite often leave nothing more than a pinprick at first, with more severe symptoms developing hours or days later.
But the danger of spiders pales in comparison to another member of the arachnid family: scorpions, whose venomous stings cause immediate searing pain, severe reactions and sometimes death.
“In terms of innate fear, scorpions would be a much better candidate for aversive reaction than spiders. But as an arachnologist, I rarely hear about peoples’ fear of scorpions,” Vetter said. “Nor do scorpions enjoy the same monster-like status in popular culture.”
With this in mind, Vetter and colleagues from five universities across the United States set out to study fear of spiders and scorpions among 800 students in Green Bay, Wis.; Cooke-ville, Tenn.; Athens, Ga.; Tucson, Ariz.; and Riverside, Calif. The Wisconsin site is the only location devoid of scorpions, while the Arizona location is the only one to host a potentially deadly scorpion, Centruroides sculpturatus, commonly known as the Arizona bark scorpion.
The researchers used the well-known “Fear of Spiders” questionnaire, which they adapted to measure fear of scorpions. The participants were asked to agree or disagree with statements such as, “If I saw a spider now, I would leave the room,” and, “Spiders are one of my worst fears.” The scientists predicted spider fear would be higher than scorpion fear overall, with students in Arizona being the most fearful of scorpions, and those in Wisconsin the least fearful.
Published June 13, 2018, in the non-peer reviewed “Musings” section of American Entomologist, the results surprised them: respondents from all locations reported being more fearful of scorpions than spiders.
“The results from our survey blew our predictions to smithereens,” Vetter said. “Not only were people more afraid of scorpions than spiders at all universities, but scorpion fears in Wisconsin were equal to or higher than scorpion fears in Arizona. The fact that students in scorpion-free Wisconsin registered such high fear scores is mind boggling.”
Vetter said it’s possible that exposure to arachnids leads to habituation and therefore lower scores, which also might explain why scorpion fear was low among Arizona students.
“Are high scorpion fear scores in Wisconsin due to fear of the unknown and the unfamiliar?” asked Vetter, who said the paper’s inconclusive findings open the door for psychology researchers to explore scorpion fear, which is much less studied than spider fear.
“By adding scorpions to the research mix, psychologists might be able to get a better understanding of arachnid fear in humans,” he said. Source: University of California, Riverside
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Researchers found MORE THAN 600 genera of arthropods inside people’s homes. Will that freak out your customers? It shouldn’t. Here’s what you need to know.
We’re surrounded. They’re everywhere. Our customers’ homes may appear to be squeaky clean, or at least in good enough shape to host a family dinner, but there are hundreds of “party guests” hanging out inside with the humans. They’re not big, loud or messy. And we’re guessing your customers have no idea they stopped in.
They’re arthropods. You know, invertebrates that include insects, spiders and various other creepy crawlies.
“We share our spaces with many different species, and we are only beginning to understand what those species are,” says microbiologist Anne Madden, Ph.D., a researcher at North Carolina State University’s (NCSU) Rob R. Dunn Laboratory. She is the lead author of “The diversity of arthropods in homes across the United States as determined by environmental DNA analyses,” which was published in the journal Molecular Ecology. NCSU and the University of Colorado Boulder collaborated on a study of arthropods in the home, soliciting samples from more than 700 houses in 48 states. Citizen scientists provided a swab of dust from inside the home, and a sample from the outside.
The dust collected tells a dynamic story about the ecology of our homes — and the reality that our inside spaces are not so much a shelter from life outdoors, but actually a robust environment housing more than 600 different types of arthropods. “The study was not about biodiversity that is in a jungle — but biodiversity in our homes and backyards,” Madden relates, noting that their research looked at the number of species (not number of insects). “When most people are concerned about pests in their homes, they are not concerned about diversity. They are concerned because they have a lot of carpenter ants or a lot of bed bugs or cockroaches. We uncovered species that might be existing with us in our spaces, and are probably ignored. Some may not even affect us.”
For example, microscopic wasps get caught in our homes. “They may not live out their entire lives indoors,” Madden says. Many of the arthropods living among us would love to be evicted from the home environment. They show up on accident, riding in on a child’s backpack or wandering through cracks and crevices. They have no idea they’re headed toward a cushy life of carpeting, upholstery and perhaps some stray crumbs from the table.
Other species like dust mites, which showed up more often in humid regions, can be an allergy threat for some individuals. And, of course, there were plenty of nuisance flies and spiders that popped on the radar of researchers. It’s not a bad thing. Spiders, we know, are pest management professionals in their own right, snacking on some other arthropods.
“Most of the time, and this study bears it out, the ‘pests’ or arthropods in question are just an introduction,” says entomologist Jim Fredericks, Ph.D., vice president, technical and regulatory affairs, National Pest Management Association. “Arthropods are not only in the outside world, they are also present in our homes, and I don’t think that’s something that needs to be feared. Instead, it needs to be respected.”
WHAT’S IN THE DUST? So, how exactly do you find out there are 600 different buggers living in your home from a Q-tip sized sample of dust? There were a couple of strategies in place for this research that allowed scientists to find out about the creatures living amongst us.
For one, citizens’ willingness to collect their own samples to send in to the lab removed common barriers to performing this type of discovery, Madden says. Usually, collecting samples from a home means trained entomologists, working on their hands and knees, wearing head lamps and gear. It can feel a tad invasive for homeowners. Not to mention, who wants to have a perfect stranger collecting dust from all of the corners you’d prefer to ignore?
This study asked people to bag up their own dust (just a little bit of it) and invited them to get involved in the process. “It was a great opportunity to show citizens the excitement of scientific discovery,” Madden says. “The citizen science initiative allowed people to be directly involved in the research. Often, it takes a long chain of discovery with many labs and analysis and tools. I like being able to connect with people who are not professional scientists and hopefully show them the relevance of science.”
Madden adds, “Citizens can help us sample in ways we couldn’t do on our own.” The study included samples from 48 states — thanks to citizen participants. Otherwise, the map created might have been regional.
Another aspect of the study is how samples were analyzed, using high-throughput DNA analysis to identify every genus of arthropod present in the dust collected. The advanced DNA sequencing-based approach involves using robotics, data-processing software, sensitive detectors and screening so millions of tests can be conducted pronto. “Our goal was to further develop a molecular method that would allow us to gather a swab of dust and particles of DNA left behind to catalog a list of species that exists in people’s homes,” Madden says.
The findings were fascinating. For one, there are complex interactions that happen at home without us even realizing it. Many samples of DNA included tiny plant-eating aphids, ladybugs that eat them and parasitic wasps that lay their eggs in aphids — a circle of life. This robust ecology is invisible to most of us. And, it’s really pretty neat. (Arthropod diversity is good.)
Mapping the arthropod genera uncovered interesting trends. For one, dust mites were more likely to be present in homes located in humid regions. Ladybugs prefer northern homes. Turkestan cockroaches have branched out from their Southwest comfort zones and were present in the Northeast. “We found evidence of spiders and other insects that might be passing through the house,” Madden says.
“I hope that our study inspires people to find out more about the life around them, rather than being afraid,” Madden says. “By learning more, we can start to understand which arthropods could be pests.”
‘PESTS’: THINK DIFFERENT. “There was a time when we didn’t know that dust mites could trigger an allergic response,” Madden says. “And, there might be other insects we don’t know we have an allergic response to. On the flip side, there might be insects in our homes that provide some help by eating fungal spores we don’t want to live with. We’ll only know this if we do further research.”
Understanding the arthropods that live with us is an important step toward further researching their significance to our health. For instance, there is evidence that a biodiverse environment can actually desensitize us from allergies if we are exposed to many microbes at a young age.
“Timing is everything,” points out Ronald Purcell, M.D., an allergist at the Cleveland Clinic. “Studies suggest that if you are exposed to allergens, bacteria and molds before 12 months of age, the exposure might help protect you — and that makes sense because that first year of life, your immune system is learning friend vs. foe, whether that’s airborne allergies or food.”
We know that dust mites do cause some people to itch, sneeze and rub their watery eyes. “The biggest worry is uncontrolled asthma,” Purcell says, relating that most patients who come in with allergic symptoms don’t point a finger at dust mites or cockroaches. Skin testing reveals the culprits.
The presence of dust mites in humid environments, which was mapped in the study, is not surprising. “Dust mites get their water from the air, and it turns out they are 75 percent water,” Purcell says.
As for the arthropods found in the study, Purcell suspects that “most of the critters don’t seem to be a real interest from an allergy standpoint.”
PMPs who know a client has an allergy to dust mites or cockroaches might recommend a visit to an allergist, who can offer some pointers for creating a less appealing environment. For example, Purcell suggests encasements for pillows, mattresses and box springs. Wash them in hot water (120°F to 130°F) twice a month and use the hot dryer setting to kill dust mites and remove allergens. Forget the air filter. “Dust mites don’t get into the air that much,” Purcell says.
While dust mites can have a negative health relationship with humans, Madden acknowledges, most of the insects identified in the study do not. And, customers shouldn’t assume that sharing our homes with hundreds of arthropods makes our spaces contaminated or dangerous. That’s just not the case.
Instead, the research reveals intricate food webs and fascinating microbiological relationships that make homes as ecologically rich as, perhaps, the great outdoors. Madden says, “This is a different way of looking at insects and a story that rarely gets told.”
The author is a frequent contributor to PCT.
Bugs Aren’t Scary, They’re Disgusting
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Researchers at Georgia Tech University uncover how the brain reacts to seeing insects and other pests.
To determine how the human brain reacts to seeing insects and other pests, Orkin partnered with the Georgia Institute of Technology (Georgia Tech) on a scientific research study.
Georgia Tech researchers discovered that pests seen in a home elicited the neurological reaction of “strong disgust,” an emotion associated with avoiding contamination and disease.
“We expected to find that the study participants were afraid of pests,” said Orkin Entomologist Mark Beavers, Ph.D. “The reaction of disgust is actually very significant, as many of the common household pests shown in the study can contaminate food and spread disease. It’s amazing how the human brain has adapted to the potential problems posed by many of these pests, and reinforces why we all should take precautions to keep such pests away from where we live, work and play.”
STUDY DETAILS. Georgia Tech researchers used a functional Magnetic Resonance Imaging (fMRI) machine to monitor participants’ brain activity and heart rate. Inside the fMRI machine, researchers showed participants a series of video clips depicting insects and animals in different environments. They were shown common household pests (including cockroaches, bed bugs, flies, spiders and rodents), as well as video clips of “frightening” animals (including sharks, lions and crocodiles).
Participants also were shown video clips of everyday occurrences (such as a waving flag), to serve as a control condition to compare neurological responses. Video clips were displayed in a random order, each clip lasting 15 seconds.
With nearly every participant, the pest videos triggered a reaction in the brain’s insula, a region deep in the cerebral cortex associated with disgust. The amygdala, a portion of the brain associated with fear, was only triggered by videos of frightening animals.
“Insects in the home produced more disgust in the brain than insects in the wild, especially cockroaches,” said Dr. Eric Schumacher, director of Georgia Tech’s Center for Advanced Brain Imaging. “Our research suggests that we may be conditioned against pests in the home, because they may be associated with contamination or illness,” he said.
Twenty adults participated in the study, including 12 females and eight males.
Participants also ranked their own anxiety while viewing videos of pests, using a hand-held rating device and through a post-scan survey. Seventy percent of the participants ranked their level of anxiety while viewing images of household pests as either mild, moderate or severe.
The study was presented by Georgia Tech researchers at the Cognitive Neuroscience Society (CNS) meeting in 2017. After receiving interest by peers at the conference, Georgia Tech is pursuing publication of the study in a medical journal. Source: Orkin