Why Do Lice Even Exist?

Written by Justin Sexton
Published: September 15, 2023
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Lice can be very annoying creatures for pets and humans alike. They can itch your scalp, skin, and are pesky animals to get rid out of hair or fur. In an ecosystem, every animal has a purpose. Yet, with annoying animals like lice, bedbugs, or even flies, we easily question their purpose? Because they’re very annoying to larger organisms like pets and humans. However, lice exist for one reason or another.

General Information

Lice are insects that can live on humans and animals. They have two sub-species: Pediculus humanus capitis (head louse) and Pediculus humanus humanus (body louse). The head lice are 1/8″ long and establishes a home in human hair. Lice can lay eggs and multiply very quickly, making them a pesky group of insects to get rid of. However, they can die between one to two days after falling off their hosts. They live off the blood of their hosts.

Pet and Human Transmission

Three friendly happy playing dogs in summer park. German shepherd, american staffordshire terrier and french bulldog holding one stick. Different dog breeds have fun together.

Three friendly happy playing dogs in summer park. German shepherd, american staffordshire terrier and french

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holding one stick. Different dog breeds have fun together.

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An infected pet can transmit lice to another pet or a group of pets like dogs. Pets can obtain lice through contaminated leashes, collars, or grooming tools. Although they can crawl, lice can’t fly, hop, jump, or run. For humans, their means of contracting lice is similar. They have to catch it thorugh direct contact with another human who has lice. They also need to get in contact with contaminated bedding, brushes, and clothing to have lice.

One can easily tell of a lice infestation by a persistent itching of the scalp for humans, and overall itching for animals. Another way to tell is to look for nits. Nits are tiny brown or yellow lice eggs that attaches to the hair. It’s easier to see the nits than the lice due to the nits being bigger.

Why Do Lice Even Exist?

A research study in 2009 foucsed on finding the purpose of lice. The University of Nottingham in the United Kingdom conducted the study. Professor of parasitology Jan Bradley focused on how parasites help condition the mammailian immune system. Her study involved how the lice affected the immune system of wood mice.

Other studies have shown that head lice are more beneficial than body lice for this case. It sounds crazy, but lice can act like a natural flu shot. Except that they don’t help with the flu. They help with other infections such as immune dysfuncitons. In the Nottingham study, they mentioned the certain immune dysfunctions they help prevent such as asthma, arthirist, multiple scleroisis, or an allergic response.

The photo featured at the top of this post is © Photo-Vista.de/Shutterstock.com

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About the Author

Justin is an A-Z Animals Writer that loves to cover places, unique natural disasters, and travel. He has eight years of experience as a writer in the medical and media fields. He wrote for the likes of VCU Health, theMSQshop, PayDay LA, and Comic Book Resources under the penname Jay Guevara. Although he's a full time writer, Justin graduated from Virginia Commonwealth University in 2019 with a Bachelors in Health, Physical Education, and Exercise Science with a background in Community Engagement. After spending over two decades in Richmond, Virginia, Justin now resides in the suburbs of Rancho Cucamonga, California. He's a dedicated gymrat. He's also a two-time poetry author who's influenced by rappers Joe Budden and IDK along with Dante Alighieri.

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