Ticks and summertime

lone star tick female displays white spot in middle of dorsum

Lone star ticks are one of the most commonly encountered ticks outdoors in Texas.  Female ticks are identified by the single white spot (lone star) in the middle of the dorsum.

Everyone who agrees with this statement, raise your hands. “The world would be a better place without ticks!”

Ha, just as I suspected! Everyone who has ever “gotten a tick” raised their hands. Everyone else has a blank look on their face.

For the uninitiated, ticks are eight-legged arachnids more closely related to spiders than insects. While all tick species feed on blood, some feed on wild animals and rarely bite people.  Other ticks readily hitch rides on, and bite humans.  Ticks are most commonly encountered in fields or wooded areas, especially along the edges between forest and open areas.  They are generally not seen in urban sites (except brown dog ticks).

As ticks mature, their lives center around a series of hosts. Ticks typically feed on one host, then drop off to digest their blood meal, shed, and look for a new host. Species of greatest health concern in Texas are known as three-host ticks.  This means that over the course of their lifetime they will feed on three (usually different) hosts. This habit of “feeding around” sets ticks up nicely as disease carriers. A tick that feeds on an animal with a disease can pick it up and transmit it to another host.

Tick-borne Diseases

The most common human diseases transmitted by Texas ticks include Rocky Mountain spotted fever, human erhlichiosis, and Lyme disease.  Lyme disease is caused by a bacterial spirochete. Although present in Texas, Lyme disease is not as prevalent as in the north central and northeastern US.  It is thought to be carried by the deer tick, Ixodes scapularis.  Rocky Mountain spotted fever is a rickettsial bacteria disease, and is carried by both the dog tick, Dermacentor variabilis, and the lone star tick, Amblyomma americanum. It is potentially serious with a 20% fatality rate for people who go untreated.  Ehrlichiosis is another bacterial disease, with less than 10 cases reported in Texas each year.  It is less likely to have serious consequences than RMSF, but can still make you quite sick. Human ehrlichiosis in Texas is thought to be carried by the lone star tick.

Although symptoms vary somewhat among the different diseases, any time you know you’ve been bitten by a tick and come down afterwards with a rash or flu-like symptoms (aches, fever, headache), suspect the tick.  If you or a family member find a tick attached to your skin, remove the tick right away.  Instead of throwing it out, though, put it in a jar or Ziploc bag and label with the date and place you think it came from.  If you later have a rash or flu-like symptoms, check with your doctor and be sure to bring your bagged sample. If after 4 weeks no unusual symptoms occur (most symptoms should occur within a few days to two weeks), you can toss the tick with an easy mind.

Currently the University of North Texas is accepting ticks removed for humans for testing.  Follow the instructions on this site and send the living or dead tick along with a form.  Samples may be sent in by any Texas resident, and results are usually available within a week.

Because each of these diseases is caused by a bacterium, they are treatable with antibiotics.  Quick administration, however, is important.  If there is a good chance of tick-borne disease, it is usually recommended that the doctor not wait for test results before starting treatment.

Self protection

Tick app web site

The Tick App is a mobile-device friendly providing essential information for identifying and protecting yourself from ticks.

We may not be able to rid the world of ticks, but we can keep them from biting in the first place. The very useful Texas Tick App offers the following advice:

  • Wear light-colored, full-length clothing whenever possible and cover your exposed skin with DEET repellent (30%).
  • Tuck pant legs into socks to keep crawling ticks atop of clothing where they are visible.
  • For additional protection, consider using repellents containing permethrin (e.g. Permanone®) for application to clothing, or purchase clothing that has been pre-treated with insecticide for protection against mosquitoes and ticks.
  • Check yourself and your family for crawling or attached ticks.  Look thoroughly on exposed skin, clothing and hair.
  • When returning home, wash all outdoor clothing, sleeping bags and blankets in a hot water wash cycle.  Otherwise seal your things inside a plastic garbage bag to kill any wandering ticks.

Side Note:

A recent press article has me answering media calls about ticks.  The current interest stems seems to stem from a scary news story. The article focuses on super abundant ticks carrying a new disease. Unfortunately the story suffers from lack of context.  Powassan Fever, the disease in the story, is not new.  It has been known for almost 60 years. It is a relatively rare disease, with an average of 7 cases in the US annually. Also, Powassan fever, is restricted to the northern states and has never been found in Texas.

The story also predicts a bad tick season for 2017. But tick abundance varies greatly by region, and experts quoted for the story were from Cornell University in New York. A mild winter and moist spring in some areas may indeed set Texas up for above average tick numbers this year; but there’s no evidence of a tick invasion yet. So, don’t let ticks keep you indoors this summer, but don’t ignore them either.

New infographic on biting and stinging pests

striped bark scorpion
Bugs that bite sting or infect - infographic from Methodist Health System

Click on poster for a larger view. And follow MHS on Twitter  at @mhshospitals

Every now and then we get the opportunity to get a little creative with a partner who shares some of our mission. This month our partner is the Methodist Health System, and MHS Publication Specialist, Sarah Cohen.  Sarah posed a challenge to a few of us subject matter experts, and her creative team, to come up with an infographic that would help inform you about the different kinds of pests in Texas that bite, sting and sometimes infect us.

Here’s the final product and a link to the MHS news release.  It does, I think, a pretty good job of summarizing most of the important Texas (arthropod) pests that bite, sting, or pass on disease.  It’s enough to keep you indoors this summer.

Insects and mites that bite and sting seem to both horrify and fascinate most of us. On this website, over the past year, 70% of you explored publications in the category of biting and stinging pests.

But insects and mites need not be scary. Once you know what could be biting you, you can take steps to avoid them.  Knowing that the bites of only two kinds of Texas spiders are dangerous and painful, and that their webs are either cobwebs in secluded, out of the way places (black widows), or no substantial web at all (brown recluse) will have you blasting right through all those icky webs crossing the trail with no fear!  Well maybe not. But I hope this knowledge might at least make you feel a little better.

I really hope this poster doesn’t make you want to stay indoors.  A good insect repellent can protect you against biting mosquitoes, and to some extent, chiggers.  Learning how to avoid fire ants is a basic survival skill for all Texans.  And this poster offers some helpful tips on what to do if you are bitten or stung.  So get out there and enjoy the beautiful outdoors.

Just don’t step on any snakes.

 

Bed bugs happen: Even in school

kids walking to school with backpacks

A message to all parents with kids in school:  Bed bugs happen.

Bed bugs happen even in your children’s school, and like it or not we’re all going to have to deal with it. That will mean fighting the inclination to go into hyper-protective parent mode. Instead we all need to relax.  Deep breaths.  Eyes closed. Find your center.  Breeeathe… it will be all right.

It doesn’t matter what kind of school our kids attend, there’s a good chance that sooner or later you’ll hear rumors of bed bugs on campus.  I say this with some confidence because, in case you haven’t heard, these tiny, bloodsucking pests have become something of an epidemic over the past 15 years.  It’s inevitable that sooner or later children who live in infested homes will bring bed bugs to school.  While statistics are few, the numbers of public and private schools reporting problems appear to be on the rise.

Even so, the number of schools with bed bug infestations remain few and far between.  Notice the difference between a report of an introduction (one or a few bed bugs being brought somewhere) and an infestation (an entrenched, actively feeding, reproducing and sustainable community).

Schools get introductions, but almost never get infestations of bed bugs.  Why? Because schools are dynamic environments.  Our kids don’t usually sleep at school (at least not long enough to become a bug snack). On top of that, school children rarely slow down long enough to interest a shy, retiring blood-feeding parasite.  And that’s a good thing.

Schools get introductions, but almost never get infestations of bed bugs.

In fact, until this week, I had not heard of a documented case of a public or private school with a bed bug infestation.  Dr. Marcia Anderson, of the Environmental Protection Agency, enlightened me this week about a few of the schools she has investigated over the years with actual, if isolated, infestations of bed bugs.  In my opinion, however, the stories seems to be a case where the exceptions serve to prove the rule.  And such stories are rare in my experience.

bed bugs were found in this sofa

Classroom reading area with bed bug infested sofa. Photo courtesy M. Anderson.

The cases Marcia reported involved donated sofas. In some of the cases, love seats and couches were brought into classrooms for reading areas.  Children thought the furniture was a good place to toss their backpacks, and eventually bed bugs found their way from backpack to sofa. In these situations, bed bugs were able to survive for a time thanks to students and teachers who would sit for extended times, or even nap, on the comfiest furniture in school.  At least long enough to embolden a bed bug to sneak out for a meal.

In another school, discarded, but decent-looking sofas and love seat were donated to deck out the teacher’s lounge.  Turns out all of the aforementioned upholstered furniture was discarded for a reason.  It had bed bugs.  In a couple of these cases the district had the furniture steam-treated, in one case, repeatedly.  In most of the cases, the problem went away when the furniture was removed… no pesticides needed.

And that’s my point.  Even though bed bugs are easily carried from home to school, we shouldn’t assume that our schools will necessarily get overrun with bed bugs. The chance of a stray bed bug being able to safely take the blood meals required to establish a long-term new home in a school is low.  And infestations are so rare because individual bed bugs don’t commonly survive long when moved to a relatively hostile environment, like a school.

So what should schools be doing about bed bugs?  First, every school should have a policy about bed bugs.  It should involve the following:

  • Kids should not be singled out for notice, or stigmatized, for bringing bed bugs to school.  Kids have a difficult enough time without being labeled as bed bug smugglers.  Instead, the parents of kids with bed bugs should be discretely advised about the problem, and assisted with information about how to make their home bed bug free.
  • Backpacks of kids from bed bug infested homes should be isolated, or treated with heat, and the child encouraged not to put their belongings on, under or next to beds, sofas, or stuffed chairs overnight.
  • Pest control should be asked to inspect trouble spots and vacuum or steam furniture within 5-10 feet of a bed bug sighting.  Pesticides should almost never be needed.
  • Baited interceptor monitors should be placed around trouble spots and left overnight, or better yet, over the weekend.  After a week or two of this kind of sampling (and trapping), the classroom can be declared clear.
  • In the meantime, students, staff and teachers should be educated about bed bugs and what they look like.  When and whether to inform parents about an introduction should be part of the policy.
  • School nurses should be involved in the process.  A nurses office can be a safe place for a child to have their belongings thoroughly inspected or heat treated, or stored for the day.  Items with suspected infestations can usually be safely stored in a large garbage bad or smooth, vertical sided tote box that bed bugs find difficult to exit.

The good news in all this is that bed bugs are not known to carry any disease, and the chance that your child will bring home a bed bug is low.

It’s possible to both overreact, and under-react, to bed bugs.  Overreaction might result in unnecessary disruption and expense for the school, or unnecessary pesticides being used. And you don’t want that.  Under-reaction is usually due to not knowing what to do.  Inquire if your school has a policy for dealing with bed bugs.  If not, suggest that they look at our model protocol for schools (and don’t allow used sofas to be brought to campus).

And now, relax.  Deep breaths.  Eyes closed. Find your center.  Breathe… it will be all right.

 

 

Boozy beetle: the Camphor Shoot Borer

Cnestus mutilatus

Every now and then entomologists get calls that border on the bizarre. Last week I received an email from a citizen in far east Texas. He was having problems with what he said were “insects boring into his riding lawn mower gas tank”.  Of course my first reaction was that insects don’t eat plastic, nor do they drink gasoline.  Why should they be boring into a gas tank?  But the caller had photographic proof.  Not only did he have pictures of the holes, he was able to pry about 15 of the crazy insects from the plastic can and take pictures of some of them.

holes in gas tank made by beetles

Two holes (see arrows) in the gas tank of a riding mower made by the exotic camphor shoot borer, Cnestus mutilatus. Photo by Adam Sheffield.

And this wasn’t an isolated case, according to the caller.  His neighbor claimed to have had a similar experience with his mower being damaged by these same little pests the previous spring.

I’ve learned that being good at my job doesn’t mean that I have all the answers; but it does mean I need to know where to go for them. In this case I got lucky.  I put out an email inquiry about gas sniffing beetles to colleagues, and immediately got replies.

Several of my fellow entomologists recalled a publication from 2011 by Chris Carlton and Victoria Bayless at the Louisiana State Arthropod Museum.  They published a scientific note describing cases where a small beetle had been found boring into plastic gas cans.  The authors identified the beetle as a type of bark beetle called camphor shoot borer (CSB), Cnestus mutilatus.  (The finding impressed my Louisiana colleagues enough to have the can permanently stored at the Louisiana State Insect Museum.)

Cnestus mutilatus

Cnestus mutilatus, the Camphor shoot borer, is a stubby little (3-4 mm) insect that normally bores into trees. Photo courtesy Kira Metz, USDA/APHIS.

As happens too often these days, the CSB is yet another insect that’s not native to this country.  It was first reported in the U.S. in 2004, and is now found throughout the Southeast from NC to TX. It normally feeds on a variety of hardwoods, especially sweetgum. In Texas it’s more likely to be found in the eastern part of the state.

One entomologist pointed out that he has noticed these beetles often come to his alcohol-baited traps used to collect other bark beetles.  Most gasoline these days contains alcohol, so, putting two and two together, we can assume that alcohol is likely what’s attracting these little guys to lawn mowers.

How can we use what we know about this insect to prevent it from ruining lawn mowers, and perhaps causing fiery mayhem from Charlotte to Houston?  A glance at the collection data stored on BugGuide suggests that this beetle is active primarily in the spring (March to June).  Storing gas canisters and mowers in enclosed sheds or under some type of tarpaulin may be helpful, especially in the spring. Keeping the outside of the plastic fuel canisters free of spilled gas also might help.

In the case of our caller, his mower was stored in a half open car port setting.  If he could find gasoline without ethanol he might not be plagued any more; but these days that might be harder than building a new shed for the mower.

Coincidentally, this week there’s a new report of an insect that actually does eat plastic.  The wax moth, Galleria mellonella, is a caterpillar that normally bores into bee hives and consumes and digests the hive wax.  According to researchers at Cambridge University, the caterpillars are able to break down the chemical bonds of plastics much like they do wax.  The biochemists are so intrigued about the possibilities of a moth that can live off of our plastic waste that they have patented their discovery.

So a toast this week to bizarre insects!  Boozy beetles and the plastic eating caterpillars may both like to bore, but they are definitely not boring.

Bug blitz is a blast

dainty sulfur butterfly on pin

Marking perhaps the beginning of insect season, last weekend the Lewisville Lake Environmental Learning Area (LLELA) held its first ever “bioblitz”.

Collecting insects during the Bioblitz survey in Lewisville, TX.

Nets and cameras were the tools of the day for the insect bioblitz team.

In case you’ve never heard of a bioblitz, it’s a concentrated effort among volunteers, naturalists and professional biologists to go to the field and document as many species as possible over a certain time period (usually a day).  This year’s LLELA bioblitz included trees, reptiles, birds and insects.

dainty sulfur butterfly on pin

One of the cool things about bioblitz is the chance to learn new insects. This was my first time to see Nathalis iole, the dainty sulfur butterfly.

Our insect group consisted of myself and three other enthusiastic collectors/photographers (actually, mostly photographers–seems like only entomologists want to capture and euthanize insects these days).  Starting out in the prairie area of the preserve, we migrated to the very productive pollinator garden on site.  It was a lot of work, but a lot of fun too.

People often assume that professional entomologists must know a lot about the insects in the natural forests and habitats around where they live.  Of course some professional entomologists do, but many of us (like myself) are only semi-competent when it comes to sight-identifying insects outdoors.  Part of this is because there are just so many of the darned six-leggers out there, and no one can be an expert in all of them.  Part of it is because most entomologists are involved in highly specific work that doesn’t always afford the time to be naturalists.  For example, I and many of my extension colleagues usually focus on insect pests and how to control them.  Many of us are easily stumped when it comes to free-range insect life.

One of the good things that came out of the bioblitz for me was learning more about the iNaturalist tool for making biological observations. Once you establish an account in iNaturalist, you can post sightings and pictures.  The iNaturalist community will even help you identify insects.  I also learned that by adding tags to your pictures, others can search for your postings and make comments.

I’m not always a huge fan of online social networking, but this is a very useful and entertaining tool.  I found it a great way to spend some of the rainy day that followed our collecting day.

After getting home from bioblitz, the real work begins. Several hours were spent pinning insects, reviewing and culling photos, and learning how to post them online. By looking at my pictures and comparing them to iNaturalist images as well as submitting some to the more insect-oriented Bugguide.net community, I managed to identify a surprising number of insects to at least the genus level–not bad even for an entomologist.  Some of my collecting teammates were even more productive than I, having dozens of new observations posted to the web within hours of heading home.

If you want to check out some of the postings of all the LLELA blitzers on iNaturalist, try clicking here.  It might inspire you to sign up, get outside and start documenting the insect life in your own backyard.

 

 

Planting to nurture nature

white-lined sphinx moth caterpillar
white-lined sphinx moth caterpillar

Although many gardeners might shudder at the thought of caterpillars in the garden, native caterpillars are rarely serious pests to backyards trees and shrubs, and they provide an essential food source for song birds.

We all have more power than we might think.  In a world where so many things seem out of control, anyone with a small plot of land, or even an apartment balcony with room for a few potted plants can make a small but significant difference in our environment.

What we plant in our gardens can do more than just look pretty.  By selecting the right plants we can sustain native pollinators and attract butterflies.  We can create habitat for birds and reptiles and other small animals.

Imagine a songbird wanting to make a nest in your backyard.  Besides a place to weave a nest, a mother bird needs food for her young.  By far the most important protein source for song birds (including some species that are principally seed-eaters as adults) are caterpillars.  Butterfly and moth caterpillars are normally quite abundant in a natural woodlot or forest, or prairie.  But in urban areas where many of the planted trees are exotic species that sustain few native caterpillars, pickings can be scarce for nesting birds.

Many people don’t know that you can increase the carrying capacity of your backyard for birds by simply taking care to plant native trees and woody shrubs.  Dr. Doug Tallamy, University of Delaware, has documented this phenomenon in his book, Bringing Nature Home.  Tallamy also provides a useful list of woody and herbaceous plant genera and their relative attractiveness to caterpillars.  Oaks lead the list with over 500 butterfly and moth species that depend on oaks for survival.  Even though this list was compiled for the mid-Atlantic states, many of these plant genera do quite well here.  The birds will thank you.

Besides birds, bees need our help in urban areas too.  Loss of habitats, climate change and limited water are contributing to shrinking ranges and declining numbers of many unique and beautiful pollinator species.  Case in point, the rusty patched bumble bee went on the endangered species list this week, the first bumble bee to be so listed.

The Horticultural Research Institute maintains a listing of plants that bees like best.  This is a great place to start when planning a new garden.  The HRI chart is organized by bloom time, which can help you ensure that you have plants blooming throughout the growing season–an important requirement for bees and other beneficial insects.  It also lists trees and shrubs that attract few bees, like forsythia, roses, and hydrangea.

If you want to do good and feel your power multiplied, consider joining the million pollinator garden challenge a campaign to register a million public and private gardens and landscapes to support the survival and preservation of pollinators. The Pollinator Partnership even provides Ecoregion planting guides that you can download and use for even more plant ideas.  According to the website, we in north Texas and Oklahoma belong to the Prairie Parkland (subtropical) Province (though I’d just call it “hot and flat”).

So let’s get out their this summer and change something we can change–our own back yards.

 

Lady beetle invasion

multicolored Asian lady beetle adult

 

multicolored Asian lady beetle adult

The multicolored Asian lady beetle has wing covers ranging from yellow to red and with various numbers of spots. The white plate behind the head, with W-shaped markings are a good identification clue.

This year Extension offices are receiving an unusually high number of calls about lady beetles inside homes.  The culprit is an exotic lady beetle called the multicolored Asian lady beetle (MALB).  While not new, high aphid  populations in some trees last year are thought to have contributed to this year’s higher than normal number of these “naughty lady beetles”.

The multicolored Asian lady beetle is normally a helpful insect that eats aphids.  Studies of the beetle in its native Asian habitats showed that it was such an efficient predator that for many years the U.S. Department of Agriculture tried to import them.  Ironically, after repeated failures to get the beetles to establish here, the beetles mysteriously appeared on their own in a number of states during the early 1990s.  Whether these beetles were survivors of earlier deliberate importations, or whether they found their way to the U.S. on their own, no one really knows for sure.  But its one bad habit has many homeowners wishing this beetle might have stayed back in Asia.

The multicolored Asian lady beetle is unique among major lady beetles in its behavior of routinely invading homes and buildings in the fall.  In its native home in Japan, this beetle quietly disperses into the white limestone bluffs along its riverside feeding grounds.  But in the U.S. it has become a significant pest when it seeks shelter in the walls and attics and living areas of homes.

The beetles seem to become pests more often in homes surrounded by trees and forests.  They also seem to be attracted to homes of lighter or contrasting colors.  The adults enter homes through any available crack or crevice and may aggregate in attics or even living areas of the home.

Although mostly harmless, like some other common lady beetles, MALBs are occasional “nippers,” biting skin if they come in contact with humans.  They also let off a disagreeable smell when disturbed, and medical reports exist of people developing allergies to the chemicals emitted by lady beetle aggregations. But mostly these beetles are a simple nuisance, unwanted and sometimes cursed.

Although homes were invaded in the fall, this winter’s up and down temperatures have caused these beetles to get restless and move about the home in search of a way out.  When daytime temperatures reach the 80s outside, attic temperatures may reach the 90s, fooling the beetles into thinking that spring has arrived and sometimes sending them into living areas of the home or building.

Control

There are no easy ways to prevent MALB from entering homes or controlling them once inside. Caulking and sealing outside entry points is perhaps the most effective technique.  Use of residual insecticides around areas that are not easily sealed may provide some temporary control of lady beetles attempting to enter homes.  Pyrethroid insecticides are usually good for this purpose.

Once inside the beetles are best controlled by vacuuming.  Spraying insecticides on aggregations of lady beetles will  result in piles of dead insects, and undesirable smells.  Discard your vacuum bag after use if you don’t want a smelly vacuum.  Bug bombs, light traps and lady bug houses are not effective at ridding homes of these beetles.

Once the weather completely warms up, the lady beetles will eventually find their way out of the house and on to their worthy pursuit of aphids.  Until that happens, you may have to just continue to vacuum these little guys up as long as they are found.

 

Benefits of cockroach baits

placing cockroach gel bait under kitchen counter

You may not have cockroaches in your home. But cockroaches remain one of the most important indoor pests of homes, especially in multifamily housing.  If you do have occasional problems with the small kitchen cockroaches, known as German cockroaches, there is good news, and it’s as close as the insecticide shelf in your grocery store.

A story

Before starting graduate school in entomology I worked as a pest control technician out of college. One of my accounts was a sprawling, multi-story public housing complex. These visits were frustrating to me, because of the difficulty (impossibility) of putting much of a dent in the well entrenched German cockroach population that scurried back and forth among these apartments.

German cockroach adult.

German cockroaches are some of the smallest cockroach pests. Their ability to reproduce quickly, however, makes them one of the most difficult to control indoor pests.

One of my visits, however, was the home of a single mom. It was a short encounter, and I’m not sure I ever saw her again; but the mother’s gratitude for my efforts to battle the cockroaches plaguing her and her daughter made an impression on me.  The apartment was uncluttered and very clean. It was obvious she was doing her part to keep cockroaches at bay–something that made my job a lot easier and more effective. Despite the feeling that I wasn’t putting much of a dent in the overall cockroach problem in those apartments, I went home that night feeling a little better about my job in pest control.

What’s changed

Two major changes have occurred in cockroach control since the early 1980s.  First, the scientific community has learned a lot more about the health impacts of cockroaches. Besides being unsanitary and capable of spreading disease pathogens, we now have solid evidence to show that cockroaches are major contributors to asthma illness, especially among children living in infested homes.  Indeed, the feces and shed exoskeletons of cockroaches have proved to be among the most important indoor asthma causes we know of.  Children who grow up in cockroach infested apartments have higher rates of asthma, more missed school days, and more doctor visits than do their more affluent classmates from cockroach-free homes.

Second, with the discovery of effective baits, we have much better tools for cockroach control today. The insecticides available to me in 1980 were mostly residual sprays and dusts that had to be applied directly to cockroach hiding places.  If counter-tops were not cleared and covered, or cupboards not emptied before I arrived, there was little I could safely do with my carbamate and organophosphate sprays and dusts.  In addition, many of these sprays were repellent to cockroaches, something that I learned later in grad school greatly reduces their effectiveness against insecticide-avoiding cockroaches.

Today’s professional and over-the-counter insecticides are safer and vastly superior to the old insecticides.  Containerized and gel baits, in particular, have revolutionized our ability to manage cockroaches.  Although sanitation is still important for cockroach IPM, baits have shown an ability to suppress cockroach numbers even in cluttered and not-so-clean homes.

A number of studies have shown over the past 20 years that cockroach control and sanitation efforts could significantly reduce the quantity of cockroach allergens in apartments.  Indeed, the National Asthma Education and Prevention Program recommends reducing cockroach exposure as a critical step to take in reducing asthma risk.

New research

A new study in the Journal of Allergy and Clinical Immunology out this week is the first to show that cockroach baiting by itself can result in measurable improvements in the health of children. The researchers looked at the apartments of 102 children (aged 5-17 years), all of whose homes had some level of cockroach infestation.  Half of the children were assigned to homes that would be treated by researchers with cockroach baits, and half of the homes were left untreated by researchers.  All of the homes were sampled for cockroaches using Victor® Roach Pheromone Traps, and health indicators were measured for all the children (such as number of school days missed, medication used, days of wheezing, number of nights where children woke up, etc.).

placing cockroach gel bait under kitchen counter

Cockroach baits come in gel form (shown) or in plastic stations. They should be placed in crevices or as close to suspected cockroach hiding places as possible.

Treatment of homes consisted of placing either Maxforce® FC Magnum, or Advion® cockroach bait gels in areas with evidence of active cockroach infestation.  Those who put out the bait were not even trained professionals. Instead, research staffers were instructed to place baits in the back corners of kitchen cabinets, behind kitchen appliances, and inside bathroom vanities.  No other control methods were used.

The median cockroach numbers were significantly lower in treated homes vs. untreated. By the end of the study none of the baited homes had evidence of cockroach activity, compared to a 20% infestation rate of the untreated homes.

Interesting to me was that after the study began cockroach numbers in the untreated homes went from 100% infested to only 20% infested.  The authors of the study attributed the drop in untreated homes to “study effects”.  People whose homes did not get treated, but were being monitored for cockroaches, took extra pains to clean up before the research team arrived, and they conducted additional cockroach control on their own, apart from insecticide baits applied by the researchers. This lead to an almost 85% reduction in trapped cockroach numbers in the control homes.

So it’s even more remarkable that, despite the cockroach reductions in homes not receiving bait treatment, researchers still noted significantly better cockroach suppression with bait-treated homes and significant improvements in children’s health.  In treated homes, for example, children had 47 fewer days a year with asthma symptoms compared to homes that were not treated with baits. Children in treated homes also had improved lung function and significantly fewer doctor visits compared to untreated homes, despite the relatively small sample size and relatively low cockroach levels in untreated homes.

When I consider how far cockroach control has come since my days with a steel pump sprayer and smelly sprays, these results are truly amazing.

So here’s the good news for anyone living with cockroaches.  A trip to your local grocery or garden center, or a visit to one of the many online DIY pest control businesses, can secure cockroach baits that are far better than anything I had 35 years ago.  For more information about selecting and using cockroach control products, see our Extension factsheet on cockroach biology and control at https://extensionentomology.tamu.edu/wp-content/uploads/sites/3/2016/07/E-359-Cockroach-biology-and-management-2012.pdf

 

Revenge of the (cricket) nerds

Jay Falk
Jay Falk

Cornell University PhD student Jay Falk with his cricket.

One of the great mysteries of my career as a Texas urban entomologist has been understanding the clouds of crickets that descend on lights and businesses nearly every year.  So I was intrigued last summer when I got an email from a PhD student at Cornell University interested in coming down to study our swarming crickets.

Jay Falk is actually a native Texan, who grew up in the Austin area and got his undergraduate degree at the University of Texas.  That’s where he got his first introduction to crickets, watching them swirl around the lighted University of Texas Tower each fall.  That experience and an enthusiastic professor at UT led him to decide to study crickets at Cornell.

When asked why we should care about crickets, he responds, “Crickets have all these dramatic behaviors that no one notices. And, they are such an important part of the biology of their ecosystems, being an important link in the food chain.”

Some of the dramatic behaviors, he explains, includes fighting for females and territory, mating flights, bursting into bouts of song, courtship, and just surviving all the things that want to eat cricket for supper.

Jay explains that there are at least three similar cricket species in Texas, but the only one known to swarm in large numbers is the Texas field cricket, Gryllus texensis.  In east Texas, a physically identical species exists, Gryllus rubens.  The two crickets can be told apart only by their song, and by the fact that rubens doesn’t swarm.  Both crickets have two generations per year. The spring generation is relatively small, and not frequently noticed.  The second generation is bigger, and responsible for sometimes spectacular swarming flights around lights and buildings.

Gryllus texensis

Who would guess that male Texas field crickets are such fighters?

As an evolutionary biology student, Jay is interested in how juvenile experiences influence mating behavior later in life.  The male Texas field cricket is known to have two strategies for attracting mates. The first strategy is to establish a mating territory and use a loud calling song to catch the interest of a passing female.  This strategy presumes the ability of the cricket to claim a good territory and defend it from other males.  These territorial fights can be spectacular, with males locking jaws and attempting to flip their opponents over.  The victors even break out into victory dances and a special victory song.

The second strategy involves sitting just outside a calling male’s territory and attempting to woo a female cricket drawn to his rival’s calls.  Jay theorizes that these so-called “sneaker males” adopt this strategy after having previously lost to the insufferable big boys.  If his theory proves correct, you might call this strategy the cricket version of “revenge of the nerds”.

When I ask Jay why this one species of cricket has adopted this swarming behavior, he shrugged. “There’s a lot biologists don’t know about the field behavior of even very common insects like the field cricket,” he said.  Even food. Apparently there is little evidence what these common insects eat. “I feed my crickets cat food,” he said.  But it’s likely that in the field much of a cricket’s diet is decaying plant material, and the occasional smaller insect.  They are not considered important crop pests in Texas.

“Texas field crickets are a unique part of the Texas experience,” Jay added at the end of our conversation.  And I think he’s right. They are part of what makes Texas a special place, at least for an evolutionary biologist.

My rabies story

stray dogs

[Note: This is not a story about insects, though it does relate to pest control.  As an urban extension entomologist I get to train and work with pest control professionals.  These good folks often find themselves called upon to handle and remove a variety of pests, including bats, raccoons and other urban wildlife that can be carriers of rabies.  So the following post is adapted from one I recently wrote for the pest management industry, with possible relevance to the readers of this blog.]

stray dogs

“Bonnie and Clyde” are the two stray dogs biting people in my neighborhood.  The dog on the left is the one that bit me in August.  Both are still on the loose. Uncollared, stray dogs are a rabies and public health risk, and should be reported to animal control.  Photo courtesy Plano Animal Services.

Last August I was out for an early morning run when a stray dog rushed me from an alleyway and knocked me down.  In light of other dog attacks in Dallas last summer, at least one of which was fatal, I naturally feared the worst as the dog clamped onto my ankle.  But as soon as I recovered my wits enough to defend myself, the dog was off.  The whole incident probably took no more than five seconds.

Thus began my education about rabies and rabies vaccinations.  I’ve known a long time about the seriousness of the rabies virus: how when it takes hold of its victim it is almost certainly fatal; how a victim’s last days are spent in convulsions, wanting and needing water but unable to swallow due to spasms of the voicebox; and how death from respiratory failure usually takes place within 3-5 days of when symptoms begin.

Although my bite was shallow, I knew enough about rabies to realize I shouldn’t ignore it.  On the other hand, I wanted to make sure I really needed the shots (I hate shots).  I learned within a few days that the same dog had been responsible for biting others in my community, and that the local animal control was working hard to catch it and its partner. I hoped that perhaps the animal would be caught and would test negative.  In fact, several days after the attack I spoke to the head of animal control in our town who was very familiar with these criminal dogs. He told me that in his opinion, given their behavior, they were likely not rabid. He explained that almost always a dog that has become infectious will show symptoms of rabies including abnormal behavior, partial paralysis, or lethargy within five days of becoming infectious.

At this point I had a big advantage of knowing someone in the Texas Department of State Health Services.  Dr. Shelly Stonecipher, at my local DSHS regional office was very helpful, answering my questions for over an hour, and advising me that the emergency room was probably my best, and most affordable, option.  My county health department, I was told, should have the necessary vaccines on hand, but would not take insurance and would have to charge the full wholesale cost of the vaccines.  This was my first big shock.  The health department cost for the first shot alone would likely be around $2,000.  The emergency room would be more expensive, but at least it would be covered by my health insurance.

Dr. Stonecipher explained that post-exposure treatment of rabies is very effective, but to work it needs to be given before symptoms occur (some sources say vaccination should take place within 1-6 days, other sources 10 days or more…a disturbingly loose margin of error). The treatment consists of five shots.  The first shot, called the human rabies immune-globulin shot, is given only if a bite has taken place and infection possibly already occurred.  The purpose of this shot is to confer rapid, though shorter lived immunity to the rabies vaccine.  This was the most uncomfortable of the injections, though not as bad as what I was told rabies shots used to be like (painful injections to the abdomen were the standard treatment up until the 1980s). I was told by my emergency room doctor that at least half of the 10 ml immune-globulin shot is supposed to be administered as close as possible to the site of the bite.

One online source says this shot should be given the day of the bite.  However, in my case, no one I talked to in the medical community seemed especially urgent about my getting the shot immediately. I thought I could wait up to 10 days, the quarantine time for some domestic animals.  This would, I’d hoped, buy some time for the dog to be caught [It never was caught and is still, six months later, on the loose in my community–our neighbors now refer to them darkly as Bonnie and Clyde].  As it was, I waited eight days; but if I had to do it over I probably would not have waited more than five days.

The next part of treatment is four rabies vaccine shots given in the arm–one the same day as the immune-globulin shot, and the others on days 3, 7 and 14 after the first shot.  Rabies vaccine confers longer term immunity via antibodies.  But the vaccine may not work quickly enough to prevent rabies if someone has already been bitten by a rabid animal. That’s why these are given in combination with immune-globulin.

The vaccine shots were easy and painless compared to the monster immune-globulin shot.  This rabies vaccine series is what anyone wanting pre-exposure rabies prophylaxis would receive.  After getting my first immunization at the emergency room, I was told that the most affordable and convenient way to get the rest of the series was through one of the local clinics that specialize in vaccines for travelers. Luckily there was a Passport Health office near my workplace.  Also, I discovered that some hospitals carry rabies vaccine shots which you can get by having a prescription from your doctor and making an appointment, thus avoiding the emergency room.

I was surprised by two things regarding my dog attack.  First, no one I spoke with seemed to care or really have strong opinions on when or whether to start the course of treatment. My doctor left the choice up to me. Some medical offices seemed not to know a lot about rabies treatment. Websites had conflicting information about virus incubation periods. In other words, I was on my own to figure out what to do about my health.

My second surprise was the cost.  Even with insurance, my out-of-pocket cost for the vaccine series alone was close to $1,000.  Even more appalling, the following month the bill from the hospital arrived.  The overall bill to myself and my insurance provider for an immune-globulin shot, first vaccine, and 15 minutes of an ER doctor’s time, came to $10,179.  The itemized bill (which I had to request) listed the immune-globulin shot as the biggest expense, $8,318!  According to the hospital, after “discounts” and insurance contributions I personally still owed over $1,800.  All this to say, saving your life after a bite from a rabies infected animal is expensive–even with insurance. Estimates of cost of rabies post-exposure treatment on the Internet are highly variable, but my sticker-shock experience does not appear to be unique.

Advice for anyone working with animals

Fortunately, human rabies cases and deaths in the U.S. are relatively rare, averaging 2-3 people a year.  This low rate is due to the wide use and effectiveness of the rabies vaccine, but it doesn’t mean that precautions are unnecessary. The CDC recommends that veterinarians and staff, animal control and pest control professionals, spelunkers, and rabies laboratory workers be offered the rabies vaccine.  The vaccine should also be considered for any one whose activities bring them into frequent contact with potentially rabid animals, and for international travelers who might come in contact with rabid animals (treatment may not be readily accessible in all foreign areas).

My ten pieces of advice for anyone concerned about rabies:

  • If bitten by a stray animal or any wildlife known to be a potential rabies carrier, don’t ignore the bite. Talk to your personal or ER doctor to assess your risk, and determine whether you need treatment for rabies. Wash the wound site from any animal bite as soon as you can with soapy water and iodine based disinfectant.
  • If possible, take steps to have the offending animal, like a bat, captured for testing. It could help you avoid expensive post-exposure prophylaxis. Care should be taken not to damage the head of the captured animal, as this may prevent laboratory testing for rabies. Your doctor or veterinarian, or in Texas any of the Department of State Health Services regional offices, can assist with instructions on how to submit an animal for testing.
  • Don’t attempt to feed wildlife or touch any stray or feral animal.  Use proper protective gear, including double plastic bags, when picking up dead animals.
  • Make sure your own pets and livestock, including horses, dogs, cats and ferrets, are up-to-date on their rabies vaccines.
  • If you work under conditions that bring you into close contact with bat roosts, do bat removal, or do urban wildlife control, getting the pre-exposure rabies vaccination series is highly recommended. It is much cheaper and easier than post-exposure treatment.
  • Even if you are pre-vaccinated, you may still require a series of two post-exposure vaccine boosters after a bite from a possibly rabid animal.  This is still much cheaper than post-exposure treatment. Check with your doctor.
  • When working around bats, bites sometimes go unnoticed. Bat bites may be extremely small and generally painless. ANY unprotected physical contact with a live bat puts you at risk for rabies–another good reason for rabies pre-exposure vaccine.
  • If you must handle a live bat, use thick leather wildlife gloves.
  • If you must enter areas of large bat colonies consider wearing a fit-tested respirator. Rabies is thought to be contracted only through bites; however there is some circumstantial evidence that urine or feces might on occasion be capable of aerial transmission, especially in areas of dense bat numbers.
  • If you’ve been bitten recently by a dog or other wildlife and not gotten the post-exposure treatment, consider getting it.  Rabies virus can incubate in humans quietly for months after exposure. Although ideally its best to start the shots very soon after the bite, the post exposure prophylaxis can be effective as long as it is given before symptoms appear.

Given that Bonnie and Clyde are still healthy and on the loose in my town, I know now that my emergency room visit and bills last summer were an unnecessary precaution.  But if it happened again, I wouldn’t do anything differently, except possibly start my treatment earlier. The risk of rabies is nothing to take lightly, and also I feel better knowing that I have a pre-exposure protection to a very serious health risk.

Animals at risk for rabies

Rabies is found only in mammals, especially carnivores and bats.  Animals that can and do get rabies include:

  • Skunks are among the highest risk mammals, especially in the south.
  • Raccoons are the most commonly infected wild animal in the eastern U.S.
  • Bats, have low levels of infection throughout the U.S.
  • Foxes, especially in the Southwest and eastern U.S. may be infected with rabies
  • Coyotes, are infected in rare cases
  • Unvaccinated dogs and cats can be infected with rabies. According to the CDC, dogs are responsible for 90% of human rabies exposures and 99% of human deaths from rabies worldwide.

Rodents and rabbits rarely get rabies–the woodchuck, Marmota monax, a rodent, is an exception. Other low risk animals include oppossums, armadillos, shrews, and prairie dogs. Livestock and horses can get rabies, and because of their close association with humans vaccination is recommended.