Roundworms ... Of Kings and Worms or How Kings, Commoners, and Cats Are the Same Food

  • Medical Author:
    Charles Patrick Davis, MD, PhD

    Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.

  • Medical Editor: William C. Shiel Jr., MD, FACP, FACR
    William C. Shiel Jr., MD, FACP, FACR

    William C. Shiel Jr., MD, FACP, FACR

    Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

What are roundworms in humans?

King Richard III remains were discovered in Leicester, England in 2012. While examining his remains, researchers discovered roundworm eggs. They sought to determine if he had been infected with the parasitic roundworms. Most of the roundworm eggs (15) were found in the coffin at the pelvic area of the king's remains while only one egg was found in soil surrounding the grave. The researchers found no other evidence for other parasites and concluded the evidence strongly supports the conclusion that King Richard III suffered from a roundworm parasitic infection.

Roundworms, also known as nematodes, are a common term for parasites that comprise the phylum Nematoda that contain mainly free-living species and are located everywhere on earth. Roundworms are not ringworm, which is a fungal infection. Researchers estimate there may be as many as 500,000 species, but only about 60 species infect humans and animals as parasites. The most commonly identified parasites that use us and some animals as food for survival, multiplication, and spread (transmission to others) are termed ascariasis, trichuriasis, hookworm, enterobiasis, strongyloidiasis, filariasis, and trichinosis. Each nematode has a life cycle that can be complex. Many have only part of their cycle completed in humans and animals.

What are the symptoms of roundworms infection?

Individuals infected with roundworm parasites may show: 

How to treat roundworms

Drugs (anthelmintic agents) are used to treat most infected patients and animals. Specific agents are used according to the species of infecting roundworm. Diagnosis is usually accomplished by identification of the species of infecting roundworm. This typically involves identification of the characteristic parasite eggs, usually found in the patient's feces. However, some can also be identified by their appearance in tissue biopsies, blood smears, or by immunological methods that are specific for individual types of roundworms.

How to prevent roundworms

Good hygiene, sanitation, and avoidance of certain arthropod bites (for example, black flies) are the best ways to avoid roundworm infections. In the 14th century, kings, commoners, and cats (and other animals) all had poor hygiene and sanitation that made them all susceptible to roundworm infection. Most roundworms don't readily distinguish between kings or commoners. Alas, like poor King Richard III, but for good hygiene, sanitation, screen doors, and bug repellent, go you or I!


Bacterial Infections 101: Types, Symptoms, and Treatments See Slideshow

Medically reviewed by Robert Cox, MD; American Board of Internal Medicine with subspecialty in Infectious Disease


Hökelek, Murat. "Nematode Infections." Dec. 5, 2011. <>.

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