Are zombies feasible?

Rosalind tackles this deathly question with Khalil Thirlaway from Nottingham University and Dr Suzie English from Cambridge University...

Rosalind - Zombies are most commonly known as reawoken human corpses with a hankering for brains and have long been centre stage of both films and nightmares alike. While the dead are unlikely to rise anytime soon, could anything make the living behave like zombies? There's been a mixed response on Facebook with Rachel saying, "I hope not. I'd be the first to go." And Dante speculating that The Pentagon has a panic room as a precaution in case of a zombie outbreak. This was all getting out of hand so I recruited two experts to help this week to look at both viral and parasitic possible causes. Dr Suzie English from the Department of Pathology at Cambridge University explains the main viral threat.

Suzie - Classic fictional zombies infect their victims through bites. This may be inspired by real life group or genus of viruses called lyssaviruses, commonly known for causing rabies. Once bitten, rabies infects the central nervous system. Symptoms include confusion, aggression, and the characteristic fear of water. Rabies is associated with a very large concentration of virus in saliva, leading to a high risk of transmission from bites, licks, and scratches. It has 100 per cent mortality rate once symptoms begin which is why there's been immense fear of rabies across time and cultures.

Rosalind - So, it's plausible in a viral sense, but what about zombies caused by parasites? Khalil Thirlaway is an immunology PhD student from Nottingham University.

Khalil - There are already lots of parasites that are experts at taking control of their hosts. Take the zombie ant fungus for example, ophiocordyceps. An ant comes into contact with fungal spores which germinate and grow through the ant's exoskeleton. Through mechanisms that we don't yet fully understand, the fungus takes control of the host and forces it to climb up a plant stem and clamp on to a leaf stalk. Having locked the ant's jaws shut, the parasite grows throughout the host's body producing antimicrobial chemicals to stop the body rotting. When the fungus has totally consumed the ant's insides, the fruiting body bursts out of the ant's head and spreads the next generation of spores, ready to infect more unsuspecting ants.

Rosalind - Terrifying stuff. But say, a virus or a parasite like this did exist, could it really wipe us out?

Suzie - Well researchers have looked at Hollywood depictions of zombie apocalypses to model pandemics of new emerging viruses. One 2009 study made headlines by explicitly using a light-hearted approach to play out various scenarios including whether or not to quarantine infected human hosts who have not yet turned into zombies. According to their research, a zombie outbreak could lead to the collapse of civilisation as we know it.

Rosalind - Is it feasible that a zombie-like disease could emerge in the first place?

Suzie - No, it's not likely. There's no currently known virus that produces zombie-like qualities.

Khalil - It might however be possible to engineer such a disease using the new discipline of synthetic biology.

Rosalind - I hope that allays your fears Stephen. Zombies are probably going to stay science fiction although I think I'll try and get a pass to the Pentagon's panic room just in case. Thanks to Suzie English and Khalil Thirlaway for those answers. Next week, we'll be scanning the horizons to answer Eleanor's question.

Eleanor - Why do so many people enjoy looking at views?

Georgia - Any psychologists out there who can help, you can email chris@thenakedscientists.com, find us on Facebook, or tweet @nakedscientists or you can join in the debate on the forum that's thenakedscientists.com/forum.

Suzie - Classic fictional zombies infect their victims through bites. This may be inspired by real life group or genus of viruses called lyssaviruses, commonly known for causing rabies. Once bitten, rabies infects the central nervous system. Symptoms include confusion, aggression, and the characteristic fear of water. Rabies is associated with a very large concentration of virus in saliva, leading to a high risk of transmission from bites, licks, and scratches. It has 100 per cent mortality rate once symptoms begin which is why there's been immense fear of rabies across time and cultures.

Rosalind - So, it's plausible in a viral sense, but what about zombies caused by parasites? Khalil Thirlaway is an immunology PhD student from Nottingham University.

Khalil - There are already lots of parasites that are experts at taking control of their hosts. Take the zombie ant fungus for example, ophiocordyceps. An ant comes into contact with fungal spores which germinate and grow through the ant's exoskeleton. Through mechanisms that we don't yet fully understand, the fungus takes control of the host and forces it to climb up a plant stem and clamp on to a leaf stalk. Having locked the ant's jaws shut, the parasite grows throughout the host's body producing antimicrobial chemicals to stop the body rotting. When the fungus has totally consumed the ant's insides, the fruiting body bursts out of the ant's head and spreads the next generation of spores, ready to infect more unsuspecting ants.

Rosalind - Terrifying stuff. But say, a virus or a parasite like this did exist, could it really wipe us out?

Suzie - Well researchers have looked at Hollywood depictions of zombie apocalypses to model pandemics of new emerging viruses. One 2009 study made headlines by explicitly using a light-hearted approach to play out various scenarios including whether or not to quarantine infected human hosts who have not yet turned into zombies. According to their research, a zombie outbreak could lead to the collapse of civilisation as we know it.

Rosalind - Is it feasible that a zombie-like disease could emerge in the first place?

Suzie - No, it's not likely. There's no currently known virus that produces zombie-like qualities.

Khalil - It might however be possible to engineer such a disease using the new discipline of synthetic biology.

Rosalind - I hope that allays your fears Stephen. Zombies are probably going to stay science fiction although I think I'll try and get a pass to the Pentagon's panic room just in case. Thanks to Suzie English and Khalil Thirlaway for those answers. Next week, we'll be scanning the horizons to answer Eleanor's question.

Eleanor - Why do so many people enjoy looking at views?