In modern films, zombies are often depicted as being created by an infectious virus, which passes on via bites and contact with fluids.
Harvard psychiatrist Steven Schlozman has termed the condition of zombies ‘Ataxic Neurodegenerative Satiety Deficiency Syndrome’ in a hoax article.
Viruses are microscopic infectious agents that come in many shapes and sizes. Unfortunately viruses do not contain the necessary components needed to carry out the basic chemical reactions required for life.
Because they can’t live on their own they infect host cells of other organisms to help them survive and reproduce. Like a parasite, viruses need to find ways to spread to new host cells in order to continue living. They have discovered many different ways to spread to new host organisms. The influenza virus transmits through a sneeze or a cough. Many have the ability to change the DNA of the host cell. Some viruses have even found ways to change the behavior of the host organisms.
Rabies is a form of encephalitis (inflammation of the brain) that can make humans aggressive and by attacking the central nervous system, it can make the body send out extra impulses to the muscles increasing their strength, which could explain why zombies are so strong and why the have bad coordination.
Rabies is caused by an RNA virus belonging to the order Mononegavirales. All warm-blooded animals, including humans, are susceptible. When a wild animal is bitten by a rabid animal the virus enters the bloodstream, eventually spreading to the spinal cord and brain. Clinical signs of rabies are quite variable, with a change in behavior being one of them more consistent findings.
This behavior change can be as subtle as apprehension, or as extreme as biting in a normally friendly dog. Dogs might chew at the site they were bitten when they became infected, and can even maim themselves. As the disease progresses dogs may show increased irritability, viciousness, excitability, and eating unusual objects, like wood. These dogs may hide in dark or quiet places, and will bite when provoked. Central nervous system signs like seizures will exhibit, and there may be paralysis prior to death. A phase of the disease causes paralysis of the muscles in the throat. This leads to excessive drooling and choking sounds due to an inability to swallow.
Could a form of rabies be a future zombie virus? Viral warfare is a weapon that a few countries have already invested in. In 1918 the infamous influenza virus was successful recreated in a lab.
Solanum is a fictional virus in Max Brook's Zombie Survival guide. Solanum works by travelling through the bloodstream, from the initial point of entry to the brain. Through mean not yet fully understood, the virus uses the cells of the frontal lobe for replication, destroying them in the process. During this period, all bodily functions cease. By stopping the heart, the infected subject is rendered "dead."
The brain, however, remains alive but dormant, while the virus mutates its cells into a completely new organ. The most critical trait of this new organ is its independence from oxygen. By removing the need for this all-important resource, the undead brain can utilize, but is in no way dependent upon, the complex support mechanism of the human body. Once mutation is complete, this new organ reanimates the body into a form that bears little resemblance (physiologically speaking) to the original corpse. Some bodily functions remain constant, others operate in a modified capacity, and the remainder shut down completely.
Origins of zombies