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Top 6 most dangerous human parasites ever discovered: The medical world is shocked

Life has many different types and forms. Sometimes, there are species that use the sun’s rays to generate energy – like plants, while there are species that choose to parasitize and harm the host.

1. Blood fluke

There is a fact that not everyone knows, that is Napoleon once faced an infection caused by flukes in the blood. These notorious parasites cause a condition called schistosomiasis (aka bilharzia) and to make things worse, not one but more than half a dozen species of the genus Schistosoma consider humans are their hosts.

Infection occurs through water contaminated with Schistosoma larvae (called cercariae). The larvae penetrate the host’s skin, then through the bloodstream, to the liver, intestines, urinary tract and many other parts of the body. Common symptoms of schistosomiasis are itchy skin, abdominal pain, diarrhea… However, in the later stages, it can cause serious health problems such as liver enlargement, hematuria, Prostate infections, bladder fibrosis, and infertility.

According to the WHO, more than 230 million cases of schistosomiasis have been reported since the disease was first discovered in 1851. Fortunately, the infection can now be treated easily. easily using an antiparasitic drug.



2. Dracunculus (Guinea Worms)

This spaghetti-like roundworm parasite may look harmless, but it’s actually quite the opposite. The parasite that causes Guinea Worm Disease (GWD) in humans, is transmitted when a person drinks water contaminated with water fleas that contain Dracunculus medinensis larvae. Symptoms of the disease begin to appear usually one year after infection when the larvae are adults.

The adult roundworm releases its larvae and out of the infected person’s skin by causing blister-like blisters. The patient experiences pain and burning on these blisters and must be frequently rinsed with water, which causes the blisters to burst and the parasite larvae to be released. This process can also cause serious, life-threatening bacterial infections.

Surprisingly, there are no modern drugs or vaccines that can actually treat GWD. Only when adult dracunculus appears on the skin through the wound can the patient clear the parasite from his body.



Dracunculus was formerly endemic to a large swath of Africa and Eurasia, but it is now endemic to only five countries: Chad, Ethiopia, Mali, South Sudan and Angola, with most cases in Chad and Ethiopia.

3. Tapeworms

Also known as Taenia, this ribbon-shaped worm can give you seizures if it forms cysts inside your brain. However, their most common habitat is in the intestines of humans (or pets).

Taenia Solium larvae can enter a person’s body when he or she drinks contaminated water or eats undercooked pork or beef containing tapeworm cysts or eggs.

Not everyone infected with tapeworms has seizures, it only happens when Taenia larvae affect the central nervous system in humans. In these cases, it is virtually impossible to diagnose or treat a tapeworm infection because the patient does not have any symptoms. Usually, this species will affect the small intestine and cause constipation, diarrhea, abdominal pain, etc. In more severe cases, it can lead to seizures, blindness, meningitis and many other neurological problems. Tapeworms are responsible for 30% of epileptic cases in many endemic areas where grazing pigs and humans live in close proximity.



Tapeworms are also one of the most common dangerous parasites. It is estimated that 5% of Americans have tapeworms, but most are not aware of this.

4. Liver fluke

The infection is known as fascioliasis and it occurs when an individual consumes water or raw plants containing liver fluke larvae. Fascioliasis and Fasciola gigantica are the most common liver fluke parasites found in humans. They mainly infect the bile ducts and liver, but in rare cases, the brain, pancreas, and eyes can also be affected. Research shows that fascioliasis threatens the health of more than 150 million people worldwide.

However, fascioliasis is not a deadly infection and is mainly found in sheep, but if infected, the parasite can stay in your body for up to 30 years and can cause problems. regular gastrointestinal health problems. Symptoms of a liver fluke infection can range from fever and nausea to cholecystitis and bile duct obstruction.



5. Leishmania chagasi and Leishmania donovani

Both of these species are protozoa that can cause a dreaded disease called visceral leishmaniasis in humans. During the infection, the spleen, bone marrow, and liver are severely affected and swollen. As a result, sufferers have reduced immunity and blood cell count leading to anemia, weight loss, prolonged fever and many other bodily problems.

According to WHO, 95% of patients with visceral leishmaniasis, if not treated promptly, will lead to death. In addition, there are two other types of leishmaniasis found in humans called mucosal leishmaniasis and cutaneous leishmaniasis, which respectively cause infections of the mucous membranes and sores of the skin. However, neither of these infections is considered fatal.

6. Acanthamoeba

This amoebic parasite causes granulomatous amoebic encephalitis (GAE), a disease that leads to swelling of the brain. About 95% of patients with GAE are killed by amoebae. However, not everyone infected with Acanthamoeba develops GAE, and some patients may never develop any symptoms.



The parasite can be found in soil, chlorinated swimming pools, tap water, on contact lens surfaces, bottled water and air conditioning equipment, and it can enter the body through eyes, sores, wounds and nasal cavities.

When Acanthamoeba infects the eye, the condition is called keratitis. People with the disease face severe eye pain, blurred vision, red eyes, corneal ulcers and many other eye-related problems. In this case, early diagnosis is extremely important because if left untreated, the patient can become permanently blind due to the infection.