A parasite is an organism or living thing that lives on inside another living thing’s body for food and other things that it needs to survive and thrive. Though parasites are very small, and are often only seen with the help of a microscope, they have the ability to manipulate, harm, and sometimes even kill the victims they are living off. These victims are called hosts.

There are two types of parasites:

• Ectoparasites
• Endoparasites

Ectoparasites are the parasites that live outside the body of its host, while Endoparasites are the ones that live inside the body of their host. These parasites are further divided into several main species that can affect humans, animals and plants.

One of which is Ophiocordyceps, a zombie-themed parasite that specialize in leading ants on a suicide mission. Once it successfully penetrates the exoskeleton of an ant, it begins to take over the ant’s behavior by hijacking its mind. It then makes the ant leave its nest in search of a plant leaf that is favourable to the parasite’s growth. The infected ant then sinks its jaws into the leaf’s vein, and has no choice but to wait for death. After the ant dies, the parasite feeds on its victims inner parts, and after a few days, send a long thin stalk through the ant’s head that shoots off fungal spores onto ants nearby, ultimately zombifying them in turn.

Just like Ophiocordyceps, many other species of parasites are known to control animal behavior like the Rabies virus that infect dog’s immune system, the Gordian worm that infect cricket’s brain and the Toxoplasma which needs both cats & rats to fulfill its quest for expansion.

There are 3 main classes of parasites that cause disease in humans; Protozoa, Helminths, and Ectoparasites. Protozoa are one-celled organisms that live and multiply in the blood or tissue of humans. They infect the body via mosquitoes and flies and are found in soil or water. The Helminths parasites parasite class include; parasitic flatworms, Tapeworms, Roundworms, Pinworms, and more. They dwell in the gastro intestinal tract, blood lymphatic system, and other tissues. Ectoparasites include; Ticks, Fleas, Lice, and Mites that live on the surface of a human host and attach or burrow into the skin.