Discover how parasites control host behavior

Not only in horror movies, parasites capable of controlling hosts larger than it are many times also exist in our lives.

These are creatures that live in the host's body, they can dominate nerves and even kill the host. Unlike normal parasites that rely on hosts, these parasites are able to directly attack the brain and control host behavior to develop, reproduce and extend the life cycle.

Gordian worm

One of its hosts is cricket. Gordian worms need water to pair and reproduce, but crickets like dry land. So when they are old enough, the worms secrete a protein that distorts the cricket's navigation system, causing the crickets to jump upside down, move closer to the water source and eventually jump into the water and drown. When the worms get out of the host, they start to mate and reproduce, their eggs are eaten by insects under the water, the insects when they fly away and are eaten by crickets. From there, the Gordian worm continued to repeat its life cycle.

Rabies virus

There is also a kind of parasite that can affect the brain. Viruses often appear in dogs and move along nerves to the brain, causing inflammation and eventually killing the host. But before that, it often increased the production of rabies infection and increased hostile aggression, making the host uncontrollably increase and wanting to bite other animals, increasing the likelihood of spreading the virus.

Zombie mushrooms Ophiocordyceps

Its host is a tropical ant that often lives on a tree. After zombie spores invade the ant body by punching holes in the body, they cause ants to curl and fall from the tree. Mushrooms change the behavior of ants, make them wander in unconsciously until they stumble into leaves that are qualified for reproductive mushrooms, then, parasitic fungi come out of ants to grow and continue to spread. spores infect other ants.

Plasmodium, malaria agent

One of the most dangerous killers and also a parasite, although not controlling the brain, can still change host behavior. This parasite needs mosquitoes to mediate, which causes mosquitoes to burn more frequently and longer to transfer these viruses into the host. And other people or animals that get malaria will also attract mosquitoes, so the virus will return to the intermediate host and continue to spread, causing hundreds of millions of malaria cases each year.

Toxoplasma parasites help cats

There is a microorganism called Toxoplasma, which needs both cats and rodents to complete the life cycle. When a mouse is infected by eating cat feces, the parasite changes the chemical concentration in the rat's brain, making it less guarding. Turn them into easy prey and be eaten, and continue to spread the parasite.

In most cases, we do not fully understand how they change host behavior but what we know shows that they are truly diverse. The Gordian worm acts directly on the cricket's brain. The malaria parasite again restrained the enzyme, forcing the mosquito to burn more. Wild viruses can cause biting behavior by overloading the brain. Through all this, do you wonder if humans are dominated by parasites but are not aware of them? Because more than half of the world's organisms are parasites and probably more.