ZomBology: When Parasites Take Control

Zombology: When Parasites Take ControlJohn T. Mendenhall III

Zombies, Zombies Everywhere!

Are Zombies Possible?Zombies:A human who becomes infected by some pathogen, who then dies from the infection and is then reanimatedStrong desire for fleshLimited motor skillsNo reasoning or cognitive skills

How dead were they before reanimation?What do you need to keep a zombie alive?Could a pathogen causes zombism?

Biological vs. Clinical DeathBiological Death:Irreversible brain damage has occurred, usually from 3 to 10 minutes after cardiac arrestCells of the body are still alive but brain can no longer maintain homeostasis

Clinical Death:Stopping of blood circulation and breathing when the heart stops beating from cardiac arrestBrain is not damaged yet; recovery is still possible

What Keeps Them Going?A 30 year old, 80kg, male zombie 5,292 kcal/day5,292 kcal 22,151 kJ1 mole of ATP = 29kJ = 763.8 moles of ATPBiological death No mitochondriaNo movementNo immune system rapid decay Clinical death Cells maintain by pathogenAerobic respiration 36-38 ATP molecules/glucoseRequires O2Anaerobic respiration 2 ATP molecules/glucoseMaintain some immune system slow down decay

The Zombie DietClassic Zombies Brains 100g of human brain contains:78g water10g fat11 g protein1g carbs193 kcalZombies like Low-Carb dietsLead to slim figuresDepressionModern Zombies All flesh

Fat= 39 kJ/gProtein= 17 kJ/g

Zombie Pathogens?Are there pathogens that can reanimate a dead organism and control it like puppet?No, not yet. Most likely never.Zombism comes from Haiti and their folklore has an alternative definition for them:A person reanimated by sorcery, who has no soul, and obeys the commends of its master

History of Zombism: Vodun Vodun (voodoo) mix of Roman Catholicism and West African traditions formed when African slaves were sold to Spanish plantations in the Caribbean

3 Parts of a Person:1) Corps cadaver 2) Gwo-bon anj3) Ti-bon anjZombification the removal ti-bon anj to produce a being of no free will, that follows the orders of its master Performed by a BokurHelp person connect to the other side

How TO Make A ZombieCoupe poudre white powder causes death-like coma1) Exposure 2) Death and burial3) Recovery4) Control Wade Davis (The Serpent and the Rainbow; 1985):Analyzed the chemical composition of coupe poudre Irritants from hyla tree frogs Tetrodotoxin from pufferfish

Fact or Fiction?Economics of Zombie Workers:Making Zombies is too expensive:Coupe poudre is expensive to makeMaking Zombies is risky:Recipes for coupe poudre are not exactZombies are poor workers:Drug solution would limit their cognitive abilitiesZombification is still taken seriously in Haiti:Article 246: It shall also be qualified as attempted murder the employment which may be made against any person of substances which, without causing actual death, produce a lethargic coma more or less prolonged.

Zombism In NatureModern Zombification reanimating a dead organism through the spread of a pathogenTraditional Zombification control of a living organism by another organism to help with some taskZombie Parasites in Nature:Ophiocordyceps camponoti-balzaniiZombie-Ant FungusSpinochordodes telliniiNematomorph hairwormToxoplasma gondiiProtozoan found in mammals (mostly cats)

Zombie-Ant FungusOphiocordyceps camponoti-balzanii:David Hughes; 2011 (PLoS ONE)Ants displaying a drunkards walk and then climb to the canopy and hang from leaves about 25 cm upBits down into a vein on the underside of the leaf; death grip and ant dies2-3 days later fungal shoots burst from the top of the ants headObligate parasite adapted specifically to a single ant species but produces similar effects Control through chemical signals

Water-loving HairwormsSpinochordodes tellinii:Discovered in 1888; D. G. Biron, 2005 (Proceedings Royal Society of Biological Sciences)Grows inside arthropods Require an aquatic environment for reproduction Lead host to watery graveEmerges from dead host Spinochordodes tellinii overproduces a protein hormone already found in the host

Cat-loving Protozoan Toxoplasma gondii:Discovered in 1908Mapping of its lifecycle; 1970Primary host: Domestic cat Oocytes spread through hosts feces Eating of contaminated water or food spreads oocytes to new host Nest in muscle and nerve tissue and develop into bradyzoite cysts Transmission to primary hosts by ingestion of uncooked infected tissue

Curiosity Fed The Cat Ajia Vyas; 2007 (PNAS)Infected and none infected mice were exposed to cat urine and body odorsUninfected mice showed avoidenceMice infected with Toxoplasma gondii showed no avoidance of these areas and even some attraction to the smellFound lesions in amygdala of infected miceToxoplasmo gondii may encourage suicidal mice

Toxoplasma gondii and HumansE. Fuller Torrey; Toxoplasmo gonii and Schizophrenia, 2003 (Stanley Medical Research Institute)Infected patients with schizophreniaToxoplasmo gonii may raise dopamine levels Marianne G. Pedersen; Toxoplasmo gondii Infection and Self-directed Violence in Mothers; 2012 (Arch Gen Psychiatry)45,788 Danish mothers; 1992-1995Infected women were 53% more likely to attempt suicide or self-directed violenceWomen with the highest level of infection were 91% more likely to attempt violent acts

Resources:http://www.zombiebiology.com/what-is-a-zombie/http://www.healthstatus.com/perl/calculator.cgihttp://www.convertunits.com/from/calories/to/kJBarnes, Sue & Helena Curtis. Biology, Fifth Edition. New York: Worth, 1989: 180-182./ http://hypertextbook.com/facts/2000/AmberIqbal.shtmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/biology/atp.htmlhttp://www.quora.com/What-is-the-nutritional-value-of-eating-brain-human-specificallyhttps://answers.yahoo.com/question/index?qid=20090824182901AAb0TKH http://www.livestrong.com/article/336671-low-carbohydrate-depression/http://www.npr.org/blogs/codeswitch/2013/12/13/250844800/zoinks-tracing-the-history-of-zombie-from-haiti-to-the-cdchttp://books.google.com/books?id=x5Xt50f7HZ0C&printsec=frontcover&dq=zombie&hl=en&sa=X&ei=UQypUs3cCKaIygGmu4CQBA&ved=0CFAQ6AEwBg%22%20\l%20%22v=onepage&q=zombie&f=false#v=snippet&q=zombie&f=falsehttp://www.nytimes.com/2012/10/31/opinion/a-zombie-is-a-slave-forever.html?smid=fb-share&_r=2&http://scienceblogs.com/neurophilosophy/2007/09/13/the-ethnobiology-of-voodoo-zom/

Resources:13) http://news.discovery.com/history/history-zombies-12-6-4.htm14) http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.010351615) http://www.impactlab.net/2011/03/06/zombie-ants-controlled-by-four-new-species-of-fungi/16) http://www.scientificamerican.com/article/zombie-ant-fungus-parasite/17) http://blogs.scientificamerican.com/guest-blog/2011/12/20/master-manipulators-of-the-micro-world/18) http://www.parasitesinhumans.org/toxoplasma-gondii.html19) http://www.medscape.com/viewarticle/46367820) http://www.huffingtonpost.com/2012/07/05/toxoplasma-gondii-brain-parasite-suicide-cats_n_1651523.html21) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3329973/22) Biron, D.G., March, L., Ponton, F., Loxdale, H.D., Galotti, N., Renault, L., Joly, C., and Thomas, F. 2005. Behavioural manipulation in a grasshopper harbouring hairworm: a proteomics approach. Proceedings Royal Society B. 272:2117-2126 (doi:10.1098/rspb.2005.3213).23) Dickerson F, Boronow J, Stallings C, Origoni A, Yolken R. 2007. Toxoplasma gondii in individuals with schizophrenia: association with clinical and demographic factors and with mortality. Schizophrenia Bulletin. 33:737-740 (doi:10.1093/schbul/sbm005).24) Hughes, D.P., Andersen, S.B., Hywel-Jones, N.L., Himaman, W., Billen, J., and Boomsma, J.J. 2011. Behavioral mechanisms and morphological symptoms of zombie ants dying from fungal infection. BMC Ecology 11:13 (doi:10.1186/1472-6785-11-13).25) Vyas, A., Kim, S., Giacomini, N., Boothroyd, J., and Sapolsky, R. 2007. Behavioral changes induced by toxoplasma infection of rodents are highly specific to aversion of cat odors. PNAS 104: 6442-6447.