Where to start, bacteria? Or plague?
In this post, I hope to focus mostly on the insidious bio-agent, Yersinia Pestis aka, Y. pestis, bringer of plagues. I stray but I come back (you’ll know by my tone).

Pathogen infection blocks flea’s esophagus. Unable to feed, it jumps from animal to animal in attempt to get nourishment. During this process it regurgitates infection into each bite wound until it dies of starvation.
Plague derives from the Greek, plēgē, meaning a blow or stroke. Latin plungere, meaning to beat or strike and also to bewail or lament.
I want to indicate idea of pandemic in some way. I mention to Dr. Sandra Reuter, I am considering collaging a world map into my study of Y. pestis.
She responds: I like the idea of the world map and spreading of disease. That is very much what I am interested in now, and it does also apply to the plague, as it has travelled the world several times, too! Especially in the middle ages, it spread along the trade routes. Even today, it survives in some places like Madagascar, China, Russia, and even in remote parts of the US.
Some bugs are like that, they like to travel and make use of how people move. Compared to the middle ages, the spread nowadays is much quicker, though, because of air travel! That’s why this corona virus pandemic has hit the whole world within a couple of months, whereas the plague travelled much slower, and the big pandemic of the Black Death took several years to spread around Europe.

At start of composition, I know I want to indicate the plague and it’s history so I collage onto my surface, a global map. I want to add a phylogenetic tree but I fill the space with symbolic fingerprints instead. This detail eventually goes.
Plague, infectious disease, zoonotic in nature meaning it’s transmitted between animals and humans. The main vector, a small flea, passes causative agent, Y. pestis to another living creature, in this case, a rat, aka, the reservoir host.
Can I refer to this as one cycle? Because we also have another cycle that involves the human.

Flea is vector, rat is reservoir host (first victim), and the bacteria being passed is non-motile, rod shaped, bipolar staining (looks like a closed safety pin). I especially enjoy drawing the rat. Felt a little bad for flea. Safety pins were nearby…fun photo op.
Humans are contaminated in various ways: flea bite (blood meal / flea throw-up), direct contact with infected animal or tissue, or by inhalation of droplets coughed by infected human or animal.
While the disease is important, I get so caught up in it (fyi, it’s fascinating and there’s a lot on it, look it up). And in the case of this study of Y. pestis, I wander into genome sequencing too (and also get lost).
Trying to understand a complicated set up, I eventually have to return to the focus for my visual…the pathogenic bug.

As I look at and draw in the bacteria, I recall Sandra telling me most look fairly similar and are small. She’s right, they do and they are.
Y. pestis, Gram-negative, nonmotile, rod shaped bacterium, I’ve decided I have an aversion to you. I can’t think straight to write about you.
You are facultative anaerobic which basically means you grow (survive) with or without oxygen (with or without oxygen!). You are held by some sort of slime layer that prevents you from being destroyed by king of the phagocytes (→macrophage).

Enter neutrophil, lymph node and macrophage.(replacing fingerprints)
You manage to colonize macrophages, reaching lymph nodes, and because the immune system doesn’t take you down you can enter the blood stream and organs leading to bubonic plague, septicemic plague or pneumonic plague. And if you’re inclined, you take people down quick!
The history of the plague and the details of the various transmissions are out there to read about. And genome sequencing helps to tie up the story as it passes through time.
Though unlike my last study where I manage to pull it all together (at least in my head and on my painting surface) – this pathogen and its disease has me going from one complexity to another. I keep wishing I was painting on a large sheet of paper that I can erase and rework instead of circular, 11.5″ form. Oh well.
Questions I have as I learn about Y. pestis and its disease:
Who is the victim in the end? Every life form that comes into contact with Y. pestis, is my guess.
And who survives? (I sort of asked this question in the last post) My best guess is, it all depends on who, what and when. There are lots of fleas and rats, after all, and maybe many humans too (in other words overpopulation).
Will the bacteria be destroyed completely? Does it serve a purpose?
Does the bacteria’s nonmotile quality benefit it in some way? It seems to me it would want to move.
Any comments or questions? Please share them!
Thank you Sandra, for introducing me to your work, past and present. And helping me along as I organize my thoughts. I will say this study and how I moved through it, in some weird way, activated my imagination and maybe at times even each of my senses.
#LotsOfActivity
I especially enjoyed our conversation about DNA (and RNA) and the common thread (strands) that connects us all. I’ll hope to come back to this one day.
More → Dr Sandra Reuter and her work.
Postscript: It was hard for me to keep this information organized so I could understand. Maybe because I quit drinking coffee this last month…who knows. Anyway, it’s interesting to be looking at this topic in the context of this last year. It moves me into looking forward. All life seeks to survive.
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