13 Living Creatures Found on the Human Body

Even when you think you are alone, you are not! Less than half of the cells of your body are human with the rest being made up of tiny creatures who live on and in your body every second of the day. Each human body is a complex ecosystem that is completely unique. Some of these tiny creatures are on your skin whilst others are in your ears, up your nose, or in your intestines. Most are so tiny that you would need a microscope to see them but we don’t suggest you do that because some of them look quite scary!

Most of the time, these guys do not do us any harm. They feed on what our body has to offer and, in return, help our body function normally. As humans evolved, our ‘guests’ evolved with us. However, sometimes they reproduce to numbers that cause symptoms. Others, such as tapeworm, are parasites and do not help us at all! Let’s take a closer look at 13 living creatures on the human body.

Demodex (Face) Mites

There are two types of Demodex mites living on the human body, Demodex folliculorum (D. folliculorum) and Demodex brevis (D. brevis) but you will never see them with the naked eye because they are just 1/64 inch long. Demodex folliculorum are the most common and are found on your nose, cheeks, chin, eyelashes, eyebrows, and scalp. Demodex brevis are more likely to also move to the neck and chest area. The majority of people have them but they usually don’t cause a problem. However, they may cause itchy, flaky skin in some people. These mites live off skin secretions but never poop!

Head Lice

If you have had kids, you have probably had to do battle with head lice at some point. These pesky creatures live on human hair, eyebrows, and eyelashes. They feed several times a day by biting your scalp to reach your blood. This is what causes an allergic reaction and itching. Head lice do not jump – they crawl from one person’s head to another possibly via clothing or combs and towels. If one person gets head lice, the whole household must be treated with either prescription or over-the-counter medication.

Ringworm

You may be surprised to know that ringworm is not actually a worm – it is a fungus. The culprit lives on skin and on objects such as clothing and bedding. Ringworm on the feet is called ‘athlete’s foot’. It causes a red, itchy, circular rash and is passed directly from one person to another (possibly by sharing towels) but you can also get it from animals including dogs, cats, and horses. It is usually treated by an anti-fungal cream.

Scabies

Scabies is a skin condition caused by Sarcoptes scabiei var. hominis which is a tiny mite. They burrow into the upper layer of the skin where they lay eggs. This causes itching and a rash. To get scabies from another person, you need prolonged skin-to-skin contact or sleep in the same bed. It is most common in institutions including university dorms. The treatment is with creams or lotions but you also need to wash all bedding and put clothing in a sealed bag.

Candida

The fungus called Candida is found on most people’s bodies and usually causes no problems. The places it is found most often are the skin, inside the mouth, gut, and genitals. If it grows out of control or enters other parts of the body, it can cause itching and soreness. This is called thrush. If it gets in the bloodstream it can cause a fever.

Gut Microbiome

There is a complex ecosystem located inside your intestines. All of the organisms that live there together are called gut microbiota, gut microbiome, or gut flora. They include single-cell organisms, bacteria, viruses, and fungi – there are trillions of them! Far from causing us harm, these tiny creatures are vital for breaking potentially toxic food compounds and synthesising many nutrients. We each have out own unqiue biome – so we should look after it!

Pinworm (Threadworm)

Pinworms are small, thin, white roundworm called Enterobius vermicularis and are found most often in children and people living in institutions. They are about 0.05 inches long so you can just about see them with the human eye. They can cause itching around the bottom area. You can take oral medication to get rid of them but the whole family needs to be treated.

Tapeworm

As their name suggests, tapeworms are long and flat intestinal worms. They live in animals but some some species can live in humans including Taenia solium which you can get from pork. If you have tapeworm, you may suffer from nausea, diarrhea, and weakness but some people don’t even know they have them. They are uncommon in the U.S. thanks to animal hygiene practices.

Skin Bacteria

Healthy skin is teeming with bacteria. The most common types are Staphylococcus, Corynebacterium and Propionibacterium. There are a million bacteria in just one square cm. All these tiny guests help to keep our skin healthy and functioning as it should.

Crabs

Human crabs, otherwise known as pubic lice (Pthirus pubis), are tiny insects that live in body hair, especially around the genitals. They are passed on through sexual contact. They can cause small red or blue spots on your skin. Treatment is medicated creams or shampoos.

Chiggers

These are tiny mites that are in the same family as ticks and spiders. They are found in all countries, often in fields and forests. When they bite to feed on your skin cells, it can make you itch and they attach to your skin for several days. Once they are full, they drop off!

Hookworms

These worms were once common in the U.S. but cases are now rare. They live in the soil and penetrate the skin of the feet. From there, they travel to the intestines. Often they cause no symptoms but some people have blood loss leading to anemia.

Ticks

Unlike many other harmless tiny creatures, ticks are an animal that you do not want to carry on your body. They are spider-like creatures that feed on the blood of mammals – including us. There are several tick species in the U.S. that can transmit several nasty diseases to humans. These include Lyme Disease and Tick-Borne Relapsing Fever. They are most active between April and September.