Zombies

Natural Zombies

As far as monsters go, I used to think that zombies were one of the least likely to exist.  Then my teenagers got mobile devices.  Ha!  I’m kidding, but they do act like those phones have taken over (eaten!) their brains!

Terrifying Fungus

I’m a nature and science nerd, so I geek out on video series like Life and Planet Earth.  I would go so far as to suggest that David Attenborough create a sleep app where he reads stories or just talks about the hunting tactics of cheetahs.  I digress.  I also might have been nodding off.


It was on a Planet Earth episode that I learned about zombie ants, or rather, the cordyceps parasitic fungus that infects the ant’s brain, causing them to climb a tree to an ideal height and clamp down on a leaf or branch so that the fungus can sprout from the body of the ant which was first transportation and now fertilization.  Think that’s scary?  There are thousands of different types of cordyceps fungi and each specializes in a species of insect- moths, grasshoppers, beetles, stick bugs, even the radiation-resistant cockroach falls prey to the mind-control of cordyceps. 

Force For Good

There are times, however, when a zombie effect can be a force for good.  No, I am NOT talking about social media!  I am referring to the antibacterial activity of bacteria that is killed by chlorhexidine, also known as the Zombie Cell Effect.  I recently read an article published by the American Chemical Society (ACS Omega) found on the National Institute of Health (NIH) National Library of Medicine site. The study details the “biocidal zombie effect of chlorhexidine, a wide-scope biocidal agent commonly used in disinfectant and antiseptic formulations. The zombie effect refers to the ability of dead bacteria killed by a biocidal agent to act as efficient biocidal agents toward a new generation of viable bacteria. The killed bacteria serve as a reservoir for the antibacterial agent incorporated within them; and the new viable population of bacteria acts as a trap of the bioactive agent, shifting the equilibrium of this agent between the reservoir in the dead cells and their aqueous environment.” 
In case your eyes glazed over at the word “formulations,” they’re reporting that chlorhexidine can take the bacterial cells it just killed and insert its germ-killing information into the dead cells causing them to turn on their bacterial brothers. 

"Good character makes the best tombstone."   -Charles Spurgeon

This zombie effect extends “to both Gram-negative—Pseudomonas aeruginosa PAO1—and Gram positive—Staphylococcus aureus—representative bacteria; showing that the zombie effect is maintained in the second and third generations; showing the effect to operate in an environment of growth media, which extends it to life-supporting environments; and proving that cross-killing is possible, that is, killed S. aureus cells fully inactivated viable P. aeruginosa.”

If you’re yawning again, this scholarly report is saying that chlorhexidine can make pathogen-killing zombies out of both bacteria that can cause lung infections, swimmer’s ear, and skin infections from pools and hot tubs,  and staph infections which can cause common sinusitis or become as serious as MRSA.   If growth conditions are good, this effect can continue with zombies spawning more zombies.  It’s reminiscent of an epic battle where the bad guys become good guys and begin fighting against the bad guys in the middle of the battle. Then those new good guys convert more good guys again and again.  What an incredible way to fight a pathogen! 

Apocalypse Averted

This Zombie Effect spawns more hope than fear!  It just so happens chlorhexidine also has antifungal properties.  Maybe now I can watch the cordyceps episode again without the nightmares.

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