The Black Death: Do Fleas Really Deserve All the Blame?

The Black Death was one of the most devastating events in history.   Originating from central Asia, it is believed to have traveled along the Silk Road until it reached the Crimea around the mid-1340’s.  From there it spread to become a pandemic in the truest sense of the word.  The Black Death was responsible for the deaths of an estimated 30-60% of the European population, and as many as 100 million deaths worldwide.   You all probably know this much already.  You also probably know that this was vectored via the Oriental rat flea (Xenopsylla cheopis) living on black rats that made their way on merchant ships in the Mediterranean initially and then ventured north.  The Oriental rat flea is a nasty bugger, vectoring not just the plague (Yersinia pestis) but also Rickettsia typhi, and tapeworms.  But what if we can scratch one of those off that list?

Oriental Rat Flea

Skeletons unearthed a year ago during a work on a new rail line in London are shedding new light on some of our well established ideas regarding our not-too-distant past.  The bones were believed to be from a cemetery of plague victims.  Molars were removed from the skeletons and DNA then extracted from the teeth.  The plague bacterium was found in several of the teeth, indicating these individuals were exposed to and most likely died from the Black Death.  These results are not unexpected, of course so researchers continued to “dig”.  Archaeologists, geologists, historians, physicists, and microbiologists worked to better understand the circumstances surrounding these individuals lives and deaths.

They were generally poor people showing clear signs of malnutrition, and a history of hard labor.  One may have even been a vegetarian later in their life, possibly indicating a shift to monastic life at some point.  Not completely surprising considering the land was at one time part of a monastery.  These plague victims didn’t come from the same time period either.  With radiocarbon dating indicated the graveyard was used multiple times between the earliest outbreaks (1348-1350) and later ones in 1361 and the early 15th century.  Archaeologists are planning on more digs as they estimate the total number of bodies may number anywhere in the “low thousands”.

Black death researchers extracted plague DNA from 14th century skulls found in east London. Photograph: Philip Toscano/PA

But that’s not the whole story, not by a long shot.  I may be an history buff but I’m also a buggy person right?  So why would I be blogging about this if there were not some new interesting entomological tidbits to be shared?  Because I’m bored, yeah….fascinated with dead things, yeah…but there is buggy stuff to share!  Traditionally the belief has been that the Black Death was spread via the Oriental rat flea, as stated earlier.  But evidence derived from those teeth suggest that this may not be the case; or at least not always the case.

When researchers compared the genome from the molar-derived bacterium with that of more recent plague victims they found the genome largely unchanged.  The recent outbreaks of the plague such as in Madagascar last year saw the majority of deaths from a pneumonic or pulmonary plague.  This new information suggests that the transmission of the plague was likely not just via the rat flea but also likely the pneumonic strain.  This is a more virulent strain of the bubonic plague.  Exposure to the plague from the rat-borne fleas is treated with antibiotics and has a higher survival rate than its cousin.  The pneumonic form, acquired via inhalation and human-human contact, is very highly fatal with death typically resulting within 24 hours of exposure if not treated.  The 60 deaths attributed to the pneumonic plague (84 deaths in total) were believed to be spread in part because of increasing political turmoil in the area resulting in poor hygiene and a decline in living conditions.

This mirrors much of what is believed to have happened during the Black Death.  Political and social instability, significant decreases in living conditions and healthcare availability created a perfect storm of underlying problems.  Perhaps the rat flea gets a bit of a reprieve.  Initial introduction via the rats is likely to have occurred with the more virulent strain of pneumonic plague taking over and doing the most damage.

Research continues and I look forward to hearing about it.

 

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Miss me? Come see me in Austin

Slide2To say I’ve been slacking would be incorrect but I understand you all may be feeling neglected.  I’m about to head to Austin for the annual meeting of the Entomological Society of America where I will be presenting both a ten minute talk and a poster.  Let this be a lesson to you my faithful readers…never agree to do both a talk and a poster.

For those who care the talk will be Monday morning some time (I should look that up before it’s too late) and I’ll be rambling about these little caterpillars which cause problems in lawns and golf courses. Yup.  Exciting stuff, eh?  The poster will be up for most of Wednesday and I’ll be there at some point (again, should look into that) to answer your questions.

Sod webworm larvae on bentgrass turf

The poster is an interesting thing.  The way the ESA has their submission process, you submit the abstract and title five to six months prior to the event and once it’s submitted, that’s it.  So you can have the best of intentions, or think you know where things are going to take you…and then you find out that’s not the way things are heading.  The topic of my poster relates to an issue I have regular experience with; Delusory Parasitosis.  I will blog more about this in the days to come but essentially it’s the belief that you are being infested/bitten/attacked, etc. by insects, mites or some other organism.  There are many causes of this phenomena and as an Entomologist I am of course not able to diagnose any of them.  We just look at the signs we can observe and get a good feel for what the situation may be.  One of the hallmarks of this situation is the individuals refusal to accept that the problem could be psychological and thus, will not ever consider the forms of treatment that can bring relief to them.  Making matters worse is the shuffling around of them from doctor to doctor, with entomologists being contacted to confirm the presence (or lack thereof) of some arthropod related cause.  It is both a heartbreaking and headache inducing cycle that seems to have no solution.  At least no apparent solution to fit with current practices.

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Typical sample submitted by individual appearing to have delusory parasitosis/infestation. Tip I learned early on in my nursing days: if it’s wet and not yours, wear gloves. The same applies to Entomology.

Will a little poster at a silly conference make a difference?  Probably not.  Is it even a good poster?  Probably not.  – Hey…complete doubt of ones abilities is a key graduate student survival component. –  What I hope is to spark interest in finding more applicable solutions.  We can report the same data again and again but what good is that doing anyone?  We know what sorts of samples we receive.  We know who are most likely to come to us with these signs and we know that most likely, nothing we tell them will make them feel better or safer.  What we know, but have thus far been unable to do is get this information out to be used in meaningful and applicable ways.  Maybe I can be a part of changing that.

Pesticides & Pot

Smoke it up kids!

 

 

Yup, last year my home state legalized the use, sale, growing and distribution of marijuana.  Not just for medical purposes either.  Since then the state government has been working to figure out the best regulations to have in place and standards to keep the product safely managed.  This is going to be quite a money maker for Washington…I hope Colorado finally gets their butts moving.

Recently the WA Department of Agriculture released a list of 200 pesticides that can be used on marijuana plants.  The thing is, since this plant has been illegal for the last thirty-fourty years there are not EPA standards regarding the use of pesticides on this plant.  I’ve tried a few quick searches online to get a hold of this list but so far I haven’t found it.  I could just not be looking hard enough.  According to KUOW, a local NPR/PRI station in western Washington, this list has earned “praise” for its comprehensiveness.  I’m looking forward to seeing this list.

Aside from possible mold problems or attacks from overeager cats, there are some legitimate concerns in regard to pests of this plant.  According to RollitUp.org pests include: Mealybugs, Aphids, Spider Mites, Whiteflies, Thrips, Beetles, Caterpillars and a few others.  Basically, your pest concerns are going to be consistent with most other plants grown in similar conditions.  Growing in a greenhouse type environment?  Be ready for mealybuggs, whiteflies, thrips and especially spider mites.  Be ready for spider mites wherever you are.  Those suckers are just, well, suckers.  Some good recommendations are to encourage natural enemies (lacewings and lady beetles) to feed on your pests.  Lacewings are especially good at this.  Some of the other recommendations are maybe not so useful.  Grinding up your pests and then spraying them on the plants to serve as a sort of warning to other pests?  Why not just pee on the plant and call it good?  And the bleach-water solution just sounds like a bad idea.  But hey, feel free to smoke that bleachy-leaf bro.*

When I see the list I’ll update you on what I think.  I am particularly interested in what they will recommend for organic treatment methods.  And, keep in mind none of these are official recommendations.  It’s just a list of 200+ things you can use.  I know many who are on the everything-has-to-be-organic-raised-by-virgin-monks kick who would happily smoke a bowl.  I wonder if they will be just as picky with their pot as they are with their tomato choices?  There will very likely be organic and low-impact methods of dealing with pests and if you have low pest levels it probably won’t be that much of an issue anyway.  IPM (Integrated Pest Management) tactics are best.  Cultural and other control and treatment methods combined are the best paths to any treating any pest problem.

Just to be smart, ALL of you, if you’re using any pesticide be sure you read the labels FIRST!  If it says it’s good for grubs but you have aphids, don’t use the bloody stuff.  And, as always, if your plant is outdoors and flowering, be aware that it is likely attracting pollinators.  Bees, butterflies and other pollinators are insects and as such, can be susceptible to insecticides.

 

*Sarcasm does not act as an actual endorsement for smoking bleach drenched plants of any kind. Do not sue me…my cats need to eat.

They’re Baaaaaaaacccckkkk. The Japanese Beetles Return for the Season!

Yup, that’s right.  These adorable, shiny (OMG so Shiny!) beetles have started to return.  Even though they may be cute they can be highly destructive.  The Japanese beetles (Popillia japonica: Scarabaeidae: Coleoptera) are, as you might guess, a non-native species of beetle which made its way here a number of years ago and easily found a home in our turfgrass and other plants.

Japanese Beetle adults kicking back on my tomato plants.

Japanese Beetle adults kicking back on my tomato plants.

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Japanese beetle getting fancy with his legs on my tomatoes. Careful there mister!

Japanese Beetle larvae “grub” From Wikipedia

Their larvae often know as “grubs” (pictured below) spend their time in grass and can be responsible for some pretty serious damage to turfgrass stands; home lawns, sporting fields, etc.   They are also known to feed on some ornamental tree and shrubs.  These areas can be managed a variety of ways from planting more resistant turfgrass and plant varieties, to the use of products like synthetic pesticides or biological control methods, most notably milky spore disease.  Left unattended, they can eventually cause major damage to the grass by chewing through the roots.  And it’s not just the damage that they themselves do that you need to worry about.  You also have to worry about raccoons and skunks coming into your yard and pulling up the grass to get at those squishy, tasty grubs!  Remember Timon and Pumbaa from The Lion King!  They weren’t joking.

Timon with a tasty morsel. I think that would most likely be a caterpillar but it’s hard to tell with the way it’s drawn. Could just be a slug with a headcapsule…which isn’t really a thing.
From lionking.org

These guys overwinter in the larval stage and the adults start to emerge right about now (June – July).  The adults damage plants in a very different yet just as important way.  I’ve been finding them on my tomato plants but this isn’t one of their typical plants they go for.  To be fair, I haven’t seen them feeding so it is possible I’m just noticing recently emerged adults just hanging out on my plants waiting to fly to bigger and more tasty pastures.  The adults are skeletonizers and will eat the “meaty” bits of the plant leaves, leaving the veins intact.  They are known to happily feed on over 400 species of broad leaf plants so take your pick.  A big one that they like are grapes and this is another thing that makes them a huge potential pest.  Imagine these guys in Wine Country!?!  Please, say it ain’t so!  Not my wine!  Infested strips of grass near a winery could be potentially devastating if left uncontrolled.

So how do we deal with these guys?  Well, I keep a nice plastic container in my freezer for all of the adults I find and I just throw them in there.  This is by no means an effective method of control but it’s a great method for just collecting some beetles.  There are a couple of traps that you can buy which use pheromones to attract the beetles to the bag where they fall in and die.  The problem with this is that they ATTRACT the beetles to the general region which can actually result in a bigger problem overall.  I actually want to get one of these bags so I can snag a whole bunch of bugs, but then I will have to worry about treating my lawn somehow…I wonder if I can get my landlord to pay for that???

Bag-a-Bug. Only really effective if you want to bring more Japanese beetles onto your property.

Other, more successful control methods are chemical treatments formulated specifically for “white grubs”.  “Grubs” is a term generally reserved for the larvae of scarab beetles which also includes Masked/European Chafers as well as the June beetles.  They all will survive in the turf during their larval stages but as you might imagine, will have different points of high susceptibility to treatment.  If you know you have mostly JB’s then make your application according to their life cycle.  The latter instars (juvenile stage) and adults are the least susceptible to pesticide products (synthetic and organic) as they are a bit more hardy by that time.  The best time to treat is when the larvae are still in their first couple of instars.  In Ohio, this means late August to early September at the latest.  As many as 95% of the eggs will be laid by mid August here.  By early fall when the weather starts to cool the grubs will crawl a bit deeper into the soil and begin their hibernation state and thus no longer be susceptible to treatments.

Japanese Beetle life cycle in Ohio. Remember to make your treatments when they are most vulnerable, in those early instar stages.

If you’re like me and you want to do your home gardening a little more on the “green” side when possible there is some good news and some bad news with regard to grubs.  The good news is there are some parasitic wasps (Tiphia popilliavora and T. vernalis) which are fairly well established in the Eastern states and will parasitize the larvae.  The bad news…they aren’t really effective at controlling the beetles in this area.  They are more successful in the southern states though.  There is also a disease called Milky Spore Disease (Bacillus popilliae) which is thought by some to be useful but depending upon your region it may or may not be.  The problem here is that this disease is already present in much of the natural habitat of these beetles and therefore populations (at least here in Ohio and nearby) have already been exposed to this and similar diseases.  By introducing the milky spore to an area where it is already present you’re not going to see much success as they have already been exposed.  In the areas where it has been effective, it can take a few years (2-3) for the spore count to build up to an affective level.  Don’t use any insecticides against the grubs during that time as the grubs are needed for completing the bacterium cycle.

Other than habitat modification (slit-seeding and planting resistant grasses and ornamentals) synthetic pesticide treatments are going to be your best bet.  I can’t recommend one particular product over others but by contacting your local Entomology Extension office they can give you the heads up on which products are best.

Hope that helps some of you.  Until next time! Hakuna Matatta!

A Question for my Fellow Entomologists

What ecological service do mosquitoes provide?  Yes, there is one species that is a predator of other mosquitoes but if mosquitoes didn’t exist, what pest populations would flourish?  Besides humans that is.  I ask this because after spending a couple of hours outside in my garden I am now covered in mosquito bites and am itching like mad!  Argh!!!  Yes, I should have smothered myself in DEET or Picardin or something but that’s beside the point.  All I wanted to do was get some plants in the ground and tend my veggies and now I look like I have the Plague!!!

So I ask you…Mosquitoes: Why should I care?

Wait…insecticides kill bees? Well color me flabbergasted!

Recently I’ve been reading a lot of posts regarding the loss of 25,000 bees in Oregon.  One site that was shared with me says the death toll has risen to 50,000 however I have not seen any other sources citing this.  It may well be true.  But this isn’t the problem many are making it out to bee (get it?  Bee?  Yeah, I know…stick with the science).   Here’s the scoop on what happened…

The Linden trees apparently had aphids and the company that owns/leases that parking lot (Target) called in a company to treat the aphids.  The company used a product called Safari a very common and quite effective insecticide.  The active ingredient is Dinotefuran which, if you’ve read some of my previous posts you know it is used in a lot of insecticide products include Vectra, a flea treatment for some pets (do NOT use Safari on your pets!!!!!!!).    If you read the label for Safari, this is what it says regarding bees:

“This product is highly toxic to bees exposed to direct treatment or residues on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds if bees are visiting the treatment area.”

So what happened that caused these bees to be killed?  The company, not complying with label instructions applied this insecticide to blooming trees which were clearly being pollinated by the bumble bees.  The bees came in to obtain pollen from the trees, were exposed and then died.  These deaths have nothing to do with what is termed Colony Collapse Disorder.  How do I know?  Because these are bumble bees, not honey bees.  Apis mellifera (The European Honey Bee, which we use for our pollination services in this country) are what have been associated with CCD.

Bumble Bee (Bombus terrestris)

The European Honey Bee (sometimes called The Western Honey Bee). Apis mellifera

The Oregon Dept. of Agriculture as well as the manufacturer of Safari are presently determining what to do in regard to the company.  Whatever they decide we clearly have a problem here.  Not with insecticides, but with how these products are used and treated.  Did these people make a simple mistake and not know?  Well, as someone who had to apply herbicide for an organization before, I can tell you they were negligent in their duties as we were required to read ALL labels of the different herbicides we were going to use.  You also have to be state certified (study and pass a test) in order to apply most of these products, especially on a commercial level.

Were they fully aware of the potential damage that could be done and they just didn’t care?  I doubt malice was a factor…who goes out and says, “I’m gonna kill some bees today!?!”  No one.

No, the reality of the situation is probably much simpler yet in application, more complex.  It comes from a misunderstanding of pesticides and how they interact with the environment.  Where does that come from?  A lack of scientific literacy…as well as a need for the all mighty dollar.

Supposedly nets have been place to help prevent further bee deaths but this could easily have been avoided by following label instructions and selecting the appropriate treatment methods which can include non-synthetic chemical methods.  However, those methods are typically more expensive or just plain old more time intensive.  But sometimes taking that extra time is worth it.  And in this case, I would say adding an extra hour to the shift would have been preferable to a potential lawsuit.

***Note: After posting this I would like to add that it is possible that the company didn’t know the bees were pollinating the trees.  If they went out on a cool day when the bees weren’t flying it is possible they didn’t notice them.  Please keep that in mind.

When is a Mosquito not a Mosquito? When it’s a Robber Fly…or Anything Else Too…

A friend of mine alerted me to a news story that had the below image.  It was associated (though not located on) a story about “genetically modified” mosquitoes and how we crazy, genome-slingin’ scientists are going to destroy the planet with our lust for fame, money and power…or something.   Now, I’m not trying to make the majority of people feel bad about this for believing it initially.  Most people don’t have a clue about what “genetically modified” (what we call transgenic…Shih Tzu’s are genetically modified…we like to be accurate…but I digress) really means and just as few know much about insects.  That’s why I’m here!  To try to clear the air and help out.  Because if there’s one thing I live for… **insert concerned & loving expression**…it’s helping people.  🙂  So Bring It On!

600190_473399606081514_1907169112_n (2)

This “genetically modified” mosquito isn’t even a mosquito AT ALL!!! It’s a Robber Fly!

First off, the article I mention is right on one count and one count only; insects will be released by scientists which have had their genome manipulated (this can be done using radiation or molecular techniques) will be released into Florida.  This is NOT the first time this sort of thing has happened and in fact this exact same type of program has been done before and to great success!  What the scientists are doing (or rather did, because this was year or more ago) is part of what’s called the Sterile Release Method.

These sterile release programs are nothing new and have occurred many times. The first use of this technique successfully eradicated a major pest and health hazard the Primary Screwworm Fly. What happens is they release males that are sterile (hence the name). These males can still mate though but they won’t produce offspring with the female. Female things she’s gonna have eggs, doesn’t mate again, dies = no eggs. This has been demonstrated to be a very successful method of eradicating pests. What they are trying to do is prevent vector borne diseases (i.e. diseases transmitted by this particular mosquito species) from becoming prevalent in the US. Think about Malaria in Africa. Point two on this little thing…the mosquito we’re talking about isn’t even native. It is an invasive species and can transmit disease!

The image is that of a Robber Fly. Same order as the mosquito (Diptera = True Flies) but a completely different family (Mosquito = Culicidae; Robber Fly = Asilidae). Robber flies are predators of other insects and also sometimes pollinators.   Some are claiming is is a mosquito somewhat common in Florida called a Galliniper (Psorophora ciliata).  As I said earlier, it is a Robber Fly, though I am not certain of the actual species.  Come on, there are over 7000 species of robber flies that we know of.

Check out the below comparisons between a Gallinipper (Top) and a Robber Fly (Bottom).  First off, there are two big things that distinguish these guys, the legs and the neck.  The mosquito neck is quite constricted and you almost don’t see where the thorax and head join.  When you compare that to the robber fly you see almost a muscle builder neck by comparison!  Additionally, the heads of mosquitoes are much smaller in relation to their body than the robber flies.

Gallinipper (Psorophora ciliata) http://bugguide.net/node/view/85638

What would you rather have, sterile mosquitoes that aren’t going to reproduce…or dengue fever?
 Please stop reading that website. It’s horrid.
For more information on the program here’s a decent CNN post.