Why are leeches harmful?

Introduction

Leeches are often considered to be creepy and dangerous creatures that suck blood from humans and animals. Although they have been used for medicinal purposes for centuries, they can also cause harm to humans in various ways. In this article, we will discuss the reasons why leeches are harmful and how to prevent and treat their bites.

What are leeches?

Leeches are elongated, worm-like creatures that belong to the phylum Annelida. They are found in freshwater environments such as rivers, lakes, and wetlands, and feed on the blood of animals, including humans. Leeches have a mouth at one end that contains numerous small teeth, which they use to attach themselves to their prey and suck blood.

The types of leeches

There are over 700 different species of leeches, but only a few of them are considered to be harmful to humans. The most common types of leeches that are found in freshwater environments are the medicinal leech (Hirudo medicinalis) and the horse leech (Haemopis sanguisuga). The medicinal leech is commonly used in medicine to treat various conditions, but the horse leech is known to be more aggressive and can cause harm to humans.

How do leeches harm humans?

Leeches can harm humans in various ways, including the transmission of diseases, allergic reactions, blood loss, and infection. When a leech bites a human, it injects an anticoagulant substance into the wound to prevent the blood from clotting, which can lead to excessive bleeding. In addition, the saliva of some species of leeches contains bacteria that can cause infections.

Transmission of diseases by leeches

Although rare, leeches can transmit diseases to humans through their bites. Some species of leeches are known to carry blood-borne pathogens, such as those that cause malaria and filariasis. In addition, leeches can also transmit bacteria and viruses that can cause infections.

Allergic reactions caused by leech bites

Some people may develop an allergic reaction to leech bites, which can cause symptoms such as itching, swelling, and redness. In severe cases, anaphylaxis may occur, which is a life-threatening allergic reaction that can cause difficulty breathing, low blood pressure, and shock.

Blood loss from leech bites

Leech bites can cause significant blood loss, especially if multiple leeches attach themselves to a person. This can lead to anemia, which is a condition characterized by a low red blood cell count.

Infection caused by leech bites

Leech bites can also cause infections, especially if the wound is not properly cleaned and treated. The bacteria present in the saliva of some species of leeches can cause cellulitis, a bacterial skin infection that can cause redness, swelling, and pain.

Treatment of leech bites

If you are bitten by a leech, it is important to remove it as soon as possible. The best way to remove a leech is to gently pull it off the skin, being careful not to crush its body. After removing the leech, clean the wound with soap and water, and apply an antiseptic to prevent infection. If you experience severe symptoms such as excessive bleeding or an allergic reaction, seek medical attention immediately.

Prevention of leech bites

To prevent leech bites, it is important to avoid areas where leeches are commonly found, such as stagnant water and wetlands. If you must enter these areas, wear protective clothing such as long sleeves and pants, and use insect repellent that contains DEET. In addition, avoid swimming in areas where leeches are known to be present, and do not allow leeches to attach themselves to your skin.

Conclusion

Although leeches have been used for medicinal purposes for centuries, they can also cause harm to humans in various ways. Leech bites can lead to excessive bleeding, infections, and allergic reactions, and in rare cases, can transmit diseases. To prevent leech bites, it is important to avoid areas where leeches are commonly found and take precautions such as wearing protective clothing and using insect repellent. If you are bitten by a leech, remove it as soon as possible and seek medical attention if necessary.

References

1. Siddall, M. E., Trontelj, P., & Utevsky, S. Y. (2007). “Phylogeny of leeches (Hirudinea) based on mitochondrial genes.” BMC evolutionary biology, 7(1), 1-21.
2. Whitaker Jr, J. O. (2010). “Leeches.” Encyclopedia of Inland Waters, 2, 330-337.
3. Brouqui, P., & Raoult, D. (2006). “Arthropod-borne diseases in homeless.” Annals of the New York Academy of Sciences, 1078(1), 223-235.
4. Lee, C. Y. (2012). “Leech bites: a review.” Journal of the Royal Society of Medicine, 105(8), 330-331.