Called the new AIDS, Chagas is quickly replacing the swine flu and bird flu fears of the past. Caused by the parasite Trypanosoma cruzi, they multiply within cells of the body, and can cause severe complications within the body, the most common of which is a heart condition called chronic Chagas cardiopathy. Complications include enlarged heart, heart failure, severely altered heart rhythm, and heart attack. Other delightful effects include intestinal complications, enlarged esophagus causing difficulty swallowing, or an enlarged colon.
With everyone so worried about Chagas disease, remember, it could be a lot worse if you ever find yourself on LV-426, or the Pillar of Autumn. With that in mind, we present to you in no particular order The Top 5 Best Videogame Parasites.
The Flood - Appearing in every game of the Halo franchise except for Reach, the flood is an extremely virulent species of parasite. Extremely adaptive, it mutates its hosts through various stages of "evolution." Responsible for the consumption of the majority of sentient life in the galaxy, their destructive nature is referenced in their name, an allusion to the biblical story of the Great Flood. Truly dangerous, the entire namesake of the series was constructed purely to obliterate them.
Metroids - Genetically engineered by the bird-like Chozo to balance the ecosystem of planet SR388, Metroids eventually became the top predator on the planet. They feed on the "life energy" of their prey in a manner similar to a leech. But unlike leeches, Metroids leave all of their prey's blood and internal organs intact. Just as they can feed on their prey, they also have the power to heal, transferring stored energy into other organisms. They have the ability to seemingly hover in air, using kinetic energy stored in their bodies. Extremely dangerous and incredibly resilient, the creature is invulnerable to all weapons except ice based beams.
Headcrabs - Featured in the sci-fi FPS Half-Life, headcrabs are fairly small, but terrifying creatures. Capable of leaping great distances, they attach themselves to a host's head, clamping onto their skull using their sharp beak. They then break through the victim's skull and proceed to take over its host's motor functions. They keep their host alive in a helpless state throughout the entire process. The host appears to retain partial consciousness once the Headcrab has taken control. Standard Zombies retain a certain ability to talk, always heard as violent cries for help. Each Headcrab subspecies affects its host in a unique way, producing a Zombie extremely distinct from the other types, in both appearance and behavior. These types of zombies were presented in Half-Life 2, and include a much faster version, as well as a venomous type.
Xenomorph - based on a painting by Swiss surrealist H.R. Giger, the life cycle of the alien starts as an egg spawned from a queen. A facehugger will emerge from the egg, and seek out a nearby life form to attach itself to. When attached to the face of a victim, the hugger will implant an embryo inside the victim, after which, the facehugger will fall off of the victim and die. The embryo will then grow inside of the victim (usually in the chest), attaching itself to a vein and feeding off of the victim. After a certain point of time, the embryo evolves to the next stage of its life, the chestburster. At this point, it will exit the victim in a very direct and usually messy fashion. Once free, the alien will begin to take on appearance and abilities of the body from which it was spawned, be it human, animal, or some other creature. It usually reaches maturity within a few hours. As adults, they are stealthy, agile, and equipped with razor sharp claws, slashing tail, an inner mouth that shoots out from the first, and a borderline impenetrable exoskeleton. And acid for blood to boot. Extremely deadly, the alien xenomorph is considered by many to be the perfect killing machine in all of sci-fi.
Las Plagas - first featured in Resident Evil 4, Plaga were discovered in Spain by a group called "Los Illuminados." Plaga are capable of altering its host's behavior by attaching itself internally to the nervous system. The undeveloped parasite is found between the lungs, beneath the heart, where it can tap into the host's spinal cord, as a link to the rest of the nervous system. As it grows inside a host, the host can suffer from a number of symptoms, such as: coughing up of blood, blood flowing from the eyes, convulsions, sudden unconsciousness, hallucinations, swelling and discoloration of blood vessels, and discoloration of the iris. The victims of Plaga (such as the Ganado and Majini) become much stronger and highly resistant to pain, while working collectively to pursue their targets. As a tradeoff, hosts often lose the ability of higher reasoning. A social organism, they often attack in groups, and can quickly overwhelm an unprepared target.
