Worms are the Earth's gardeners, happily digging around in the soil, turning it over and keeping the soil fertile... the simple life. But some worm species are parasitic in nature. Their purpose is to breed, thrive while destroying their host and then spread to another unsuspecting victim. And such parasitic worms have different sub-species, that can infect humans and animals. A worm infection is the worst sort of infection to detect and get rid of. The symptoms are vague, such that the individual's health deteriorates but it is difficult to determine the exact cause of ill-health. And such worms are hardy and tough, capable of surviving through the worst conditions. One dangerous worm species is the whipworm, which infects both humans and animals. In this article, we take an in-depth look at the life cycle of a whipworm, to understand how this parasite infects and breeds.
Introduction to Whipworms
A whipworm is a sub-type of the roundworm, that is parasitic in nature. They are approximately 30 - 50 mm long with a light pink/ whitish coloring. Like most parasitic worms (hookworms, tapeworms), they have a unique body structure, built for survival and adaptation. Their lower or posterior end is thick and large, in comparison to their narrow head and mouth region. In fact, the whipworm looks like a thin whip with a thick handle at the end, which is their tail. Their reproductive organs are in the tail. The narrow head has the mouth and digestive system of the worm.
Three main types of whipworms exist. The Trichuris trichiura infects humans, while the Trichuris vulpis affects dogs. The Trichuris serrata type affects cats, but whipworm infections are rare in cats. An approx figure of 500 million humans have a whipworm infection. The whipworm is the third most common parasitic worm that infects humans. An estimated 2.2 million people in the United States are infected, with most cases occurring in the southeastern rural areas. Cases of canine whipworms occur worldwide, with a noted prevalence among shelter and pound dogs.
Life Cycle of a Whipworm
ζ The whipworm does majority of its traveling and infecting, while it's an egg. The egg is laid in the large intestine of the host. It is a single cell organism and no embryo is present, so there is no life in it, yet. It leaves the host's body through the emission of stool.
♌ The egg passes into the soil, which serves as an incubator. The soil needs to be warm, moist and dark for the egg to develop itself. First it matures into a 2-cell organism. After spending 2-3 weeks in the soil, the egg has an embryo and is ready to leave the nest, so to speak. It is now ready to infect someone.
ζ Through ingestion, the egg enters a host. The egg travels to the small intestine and hatches, releasing larvae into this organ of the digestive system. The small intestine serves as a nursery for these little ones, who bury themselves into the villi, small protrusions that come out of the intestinal wall. Here they start to grow.
♌ During the last phase of their growth, the larvae leave the small intestine and journey to the large intestine and the cecum (beginning of the large intestine). Here they burrow deep into the walls and flesh of the large intestine and reach their full size and achieve sexual maturity as well.
ζ Now fully grown, the whipworms are ready to start the breeding-thriving process. Their distinctive body design is handy over here, allowing them to multi-task. They embed themselves in the large intestine using their narrow whip end, with the mouth to dig in. Meanwhile, the thick tail end, hangs out and mates with any whipworm nearby.
♌ The mating process is complete. After 60-70 days, the female will lay eggs in the large intestine and the cycle begins anew. Now it's time to do some math. A female whipworm will lay 3000 eggs, at a minimum. At a maximum, she can lay 20,000 eggs per day. Over that, her average lifespan is 1 year if treated in time. If proper treatment is not administered and the worm manages to reinfect the host, a whipworm can live for 5 years. And it takes just 3 months for an egg to become an adult. All this adds up to an amazingly large population!
ζ The whipworm life cycle in dogs is the same as the human whipworm. The eggs of the worm cannot pass through skin or from a mother to a child, even while lactating. They can only be ingested through the mouth. Eggs can get stuck to a dog's paws and hair. So when the dog licks or cleans itself, it will eat the eggs. If a dog noses around infected feces, it could accidentally ingest some eggs.
♌ Whipworm eggs in the soil can be found on dry foods like beans and grains, or contaminate vegetables through the soil. This is especially common, if infected feces or night soil is used as fertilizer. Eating dirt or dirty hands which have touched soil or unwashed vegetables with eggs stuck to them, etc., are all ways for an individual to ingest eggs.
From the above explanation, one can understand how an infection could result in serious health complications, human and canine alike. Their high rate of birth, easy infecting method and durable body and strength, makes the whipworm a veritable foe. While strong medicines are the key to treatment, prevention and reinfection is maintained only through cleanliness. Wash hands and food repeatedly. Practice clean and proper waste disposal techniques. Avoid eating food in very rural areas, if night soil is used as fertilizer. For dogs, deworming should be done from time to time. Clean up after your dog and do not let him sniff feces on the ground. Any parasitic worm thrives with waste or dirt, so keep clean to keep them away.