Saturday, March 17, 2012

9 September 2010 – Let Slip the Bugs of War


The news is full of bedbugs these days; a quick Google search nets 1,360,000 hits. 

Bedbugs are hardly a new phenomenon; Shakespeare has Hamlet, in Act V Sc. 2 of the eponymous play, complain to Horatio about the “bugs and goblins in his life”, a contemporaneous phrase commonly taken to refer to the ubiquitous household pest.  The creatures were well-known in historical military circles as well, having been as unavoidable a feature of camp life as the lice, dysentery, and multitudinous fevers and agues that have beset soldiers since time immemorial.  The Royal Navy fought a continual war against the pests, smoking them out with burning oakum, or drowning them with paint, all to no avail; wooden walls, woollen blankets, straw tick mattresses, 18” of hammock-space to a man, and sanitation consisting of irregular dousings with seawater were simply too permissive an environment for the little monsters.

Traditional remedies for bedbugs abound.  James Parks Caldwell, a Confederate soldier interned at Johnson’s Island during the Civil War, beseeched his “Sister Belle” to send him something called “trak fire” to help him deal with the “lecti cimices, which annoy me very much, banishing sleep from my eyelids”(Note 1).  I haven’t been able to find out what “trak fire” is; but during the Civil War, a mixture of lard and sulfur was often applied as a home remedy for two close relatives of the bed bug: head lice; and the “seven-year itch” (sarcoptic mange, a parasitical skin infection cause by the mite sarcoptes scabiei, and otherwise known as “scabies” - not the Marilyn Monroe film or the compilation album by Platinum Blonde).

Another traditional recipe for dealing with bedbugs was - and still is - the botanical insecticide pyrethrum, which is a powder composed of the dried and crushed flowers of the chrysanthemum (preferably the Persian and Dalmatian varieties).  Chrysanthemums contain pyrethrins, a family of naturally-occurring cyclopropane compounds with relatively low mammalian toxicity that are very effective in paralyzing and killing insects.  The two principal compounds (Pyrethrin I and Pyrethrin II) differ only in their alcohol radical; the former terminates in an ethyl group, the latter in an ethoxy group.  Both are slightly toxic to ducks, and highly toxic to bees and sensitive fish like trout.  The molecular structure of the Pyrethrins has been used as the basis for a variety of synthetic insecticides, including Permethrin, which - in addition to being used as an insecticide for both domestic and industrial pest control - has been widely used by military forces as an insect repellant, especially as an impregnating compound for mosquito nets.

Bed bugs, which in the 1940s were virtually eradicated as a household pest throughout the developed world, have undergone a resurgence lately.  A wide variety of causes have been cited to explain their gradual return; two of the most popular are the increasing incidence of international air travel, and, of course, climate change.  Neither offers an immediately obvious explanation as to how the little critters managed to infiltrate and temporarilyshutter a Victoria’s Secret outlet in New York last week.

As is the case with most human pests, parasites and illnesses, when it comes to bedbugs, three factors seem to play a crucial role: proximity, sanitation, and the availability of an effective pesticide.  The elimination of bed bugs in the 1940s was achieved through all three, the third being the commercial availability of DDT (dichlorodiphenyltrichloroethane).  First synthesized in 1874, the effectiveness of this compound against arthropods was not discovered until the eve of the Second World War, earning Swiss chemist Paul Hermann Muller the 1948 Nobel Prize for Medicine.  In 1972, the first administrator of the US EPA, William Ruckleshaus, banned DDT for most uses in the US.  The impact of this domestic ban on the worldwide production and use of DDT, and the resultant rise in the incidence of malaria mortality, especially in India and Africa, is still hotly debated.  For the purposes of this message it is sufficient to note the correlation between the decline in DDT use, and the rise in both malaria and bedbugs.  Synthetic alternatives to DDT (e.g., the organophosphate and carbamate insecticides) tend to be either more expensive to produce, or far more toxic, or both; while natural alternatives, like the permethrins, tend on the whole to be less effective.

For those afflicted and unable to obtain DDT, malathion or bendiocarb, and who are unwilling to whip up their own batch of rendered pork fat and brimstone, other old-fashioned remedies include rubbing alcohol, steam treatments, canola oil, dry heat for cloth items, and hanging material objects “in the hot sun” to drive out the pests.

And if you see’em on the wall...



(1) There are several dozen species of bed bug in the Genus Cimicidae; Cimex Lectularius is only one of them.