Parasites – “Uninvited Guests”
Parasites and Worms That Live In Humans
There are literally thousands of different types of worms in the animal kingdom. They generally have long, slender bodies with no separate limbs.
Worms live in a variety of habitats: some worms live in the earth such as earthworms, others live in water such as the leeches and others live in a human host such as tapeworms.
The worms that live in humans or in animals are known as parasites. Parasites always live in or on their host. They eat the food supplies of their host and cause a wide range of conditions and symptoms that range from mild to severe.
3 Main Types of Parasitic Worms
- Flatworms such as Tapeworms
- Flukes such as Blood Flukes
- Roundworms such as Threadworms or Pinworms
Flatworms include Tapeworms and Flukes. Flatworms breathe and eat literally through their skin. Oxygen and nutrients literally pass through their skin. They have no separate organs for digestion or circulation.
Flatworms feed on the blood, tissue fluids, or pieces of cells inside the bodies of their hosts. Flatworms live on the skin, mouth, gills or other outside parts of a host, or they can live internally such as the ones that live in humans that infect the blood and organs.
Flatworms range in size from being microscopic to some over 20 metres long for example in the whale tapeworm. The most common types of flatworms that live in humans are Tapeworms and Flukes.
Tapeworms live in human intestines where they feed on the partially-digested food in their host’s intestines. It is a fully protected environment and they grow and thrive in these conditions. Tapeworms are parasitic worms and are most often referred to as just parasites. They literally survive through their host’s nutrients. Parasites need hosts to survive.
Flukes are a type of parasitic Flatworm. Flukes get their name from the way they look as they are flat and the word "fluke" comes from a German word "flah" meaning "flat". Flukes have at least one external sucker, which they use to attach themselves to their host.
Some flukes live on the gills, skin or outside of their hosts while others, such as blood flukes that live in humans, live internally in their hosts. Blood flukes are largely confined to very hot tropical areas such as North Africa and South East Asia and contribute to some extreme health conditions.
Some of the most common types of Roundworms include Pinworms or Threadworms, Hookworms, Ascaris (a word that literally means ‘intestinal worm’) and Heartworms.
Roundworms have hollow bodies and openings at either end and generally grow between 2-5 inches long. Roundworms are very commonly found in pets and animals such as dogs and cats and can be easily passed on to humans. Roundworms live in salt water, fresh water and the soil.
Eating contaminated foods or getting worms from contaminated pets is the most usual way to get roundworms (a category of worms). Hookworms and pinworms are often the most common types of roundworms found in humans.