Horse roundworm

The name of the Horse powder worms stands for a roundworm that has attacked a horse's organism. Every horse pasture is considered to be infested, as the eggs of a horse roundworm remain viable for up to 10 years, which means that they can be transmitted to other horses and humans for a long time.

What is the horse roundworm?

The horse roundworm is not a species of its own, but rather the common roundworm. These parasites usually attack humans, monkeys, but also bears. The roundworm manages without an intermediate host like a horse, but it can be transmitted directly from this host to humans.

The horse roundworm is considered to be particularly productive and malignant as the females can lay up to 200,000 eggs at a time, which remain viable for 10 years. In the egg of a horse powder worm there is a larva that hatches under favorable conditions. For this reason, every horse pasture is generally considered to be infested, but infections only break out under poor hygienic conditions in the horse stable.

The horse roundworm can seriously damage the intestines, liver and lungs of the horse and lead to the death of the animal, especially if the horse concerned was not healthy before.

Roundworms, and thus also the horse roundworm, belong to the group of roundworms that reside primarily in the intestines of their host and from there spread throughout the body.

Occurrence, Distribution & Properties

The roundworm itself occurs worldwide. The horse roundworm, on the other hand, is mainly to be found on horse pastures, in horse stables and in places where horses apples. This form of roundworm mainly spreads to people who work with horses or who spend their free time intensively with the animals and who also clean stables or pastures.

A foal initially has no contact with the horse roundworm until it comes to pasture for the first time. From then on, the horse roundworms are transferred from the older animals that graze there to the foal - it does not necessarily have to become infected if the immune system is healthy. Since foals already come into contact with the horse roundworm, individual worms quite often penetrate the organism and migrate through it. As a result, healthy horses develop a reliable resistance to the horse roundworm up to about the second year of life, which is why real infections become increasingly rare from this year of life.

Deworming provides the final protection against it. However, caution is advised with foals and yearlings. On average, it can be assumed that the many eggs in a roundworm will remain infectious for up to 4 years. This means that the larvae in the egg can hatch at any time and reproduce in the host themselves. In the case of the horse roundworm it is a maximum of 10 years.

The equine powderworm egg has this resistance because it has three shells. It is thus optimally protected against extreme drought, chemical substances and high temperatures.

It is estimated that around 22% of the world's human population is infected with roundworms, which not only come from a horse but also from other hosts. Around 1% succumbs to worm infections. The female horse roundworm can grow up to 40 cm long and 5 mm wide, a male worm can grow up to 25 cm long and 3 mm wide. Visually, horse roundworms are reminiscent of an earthworm.

The parasites have a life expectancy of around 1 1/2 years per individual. They can move independently and are able to penetrate the walls of internal organs such as the small intestine or the liver without the host suffering life-threatening or even serious internal injuries.

Illnesses & ailments

An infection with the horse roundworm manifests itself relatively similarly in horses and humans. The larvae are first ingested; in horses this happens by grazing in a place where an infected animal has appled. The larva enters the small intestine, hatches and perforates the intestinal wall. It then gets to the liver and finally to the lungs, where it can cause an urge to cough and, in the worst case, pneumonia. Both horses and humans cough from this and either get rid of the larva or swallow it. As a result, it gets back into the small intestine, where it now develops into a fully grown horse roundworm.

Only two months after the penetration of a not yet hatched larva of the horse powderworm can it be detected in the faeces. This means that the cause of the first appearance of the cough is not detectable in the faeces in horses and humans.

Another risk besides severe pneumonia is a blockage in the small intestine if too many horse roundworms are there. Especially in horses, but also in humans, life-threatening intestinal entanglements and blockages can occur.

Adult horse roundworms can continue to block the pancreatic ducts and lead to colic, lead to malnutrition or try to leave the host through biochemical processes and changes in the body through orifices such as the mouth or nose. An example of this is anesthesia.

Violent allergic reactions are possible to the larvae and the adult stages of the horse roundworm, which in turn lead to the death of the host. Inflammation of the lungs of an infected host can result in other complications, such as high fever or asthma attacks.