Of all parasitic diseases, malaria causes the most deaths globally. Malaria kills more than 400,000 people each year, most of them young children in sub-Saharan Africa.
Grab on to a list of some of the most dangerous parasites on Earth: Brain-eating amoeba, Naegleria fowleri. Naegleria fowleri, also known as brain-eating amoeba, generally grows in warm bodies of water. This parasite can cause brain infection called meningoencephalitis, which causes severe brain irritation.
There are three main types of parasites that can affect humans: protozoa, helminths, and ectoparasites. These parasites can live on or in the human body and cause various diseases.
Giardia is arguably the most common parasite infection of humans worldwide, and the second most common in the United States after pin-worm.
Dioctophyme (=Dioctophyma) renale, the giant kidney worm, is the largest known parasitic nematode infecting humans — adult females can reach over one meter in length. The genus has been spelled as both “Dioctophyma” and “Dioctophyme”.
Examples of parasitic diseases that can be bloodborne include African trypanosomiasis, babesiosis, Chagas disease, leishmaniasis, malaria, and toxoplasmosis.
Protozoa are microscopic, single-cell parasites. Since they're invisible to the naked eye and don't always cause immediate symptoms, protozoa are much harder to detect. People can live for years not knowing they're infected.
Parasites that can affect humans include ticks, lice, and hookworms. Without a host, a parasite cannot live, grow, and multiply. For this reason, a parasite rarely kills its host, but it can spread diseases, some of which may be fatal.
The microfilariae can live up to one year in the human body. If they are not consumed in a blood meal by a deerfly they will die. Adult worms may live up to 17 years in the human body and can continue to make new microfilariae for much of this time.
Hundreds of fossilised animals seemingly covered in worm-like creatures are the oldest hard evidence of parasitism, dating from 512 million years ago when complex animals were still new.
Often they can go unnoticed, with few symptoms. But many times these infections cause serious illnesses, including seizures, blindness, heart failure, and even death.
Sarcocystis hominis and S. suihominis use humans as definitive hosts and are responsible for intestinal sarcocystosis in the human host. Humans may also become dead-end hosts for non-human Sarcocystis spp. after the accidental ingestion of oocysts.
Superparasitism is a form of parasitism in which the host (typically an insect larva such as a caterpillar) is attacked more than once by a single species of parasitoid. Multiparasitism or coinfection, on the other hand, occurs when the host has been parasitized by more than one species.
Naegleria fowleri
Infection rates are low – up until 2012, there had been only 310 known cases worldwide – but it is the most deadly creature on the list with a fatality rate of over 97 percent. Also known as “brain-eating ameba”, the freshwater-dwelling parasite usually dines on bacteria in lakes, rivers, and soil.
Some, but not all, parasitic infections can be detected by testing your blood. Blood tests look for a specific parasite infection; there is no blood test that will look for all parasitic infections.
Parasites can live in the intestines for years without causing symptoms.
Pharmacological investigations suggested that cinnamon oil has anti-parasitic activity against flagellates, Trichomonas gallinarum and Histomonas meleagridis in chicken (18) and against Cryptosporidium parvum in murine models (19).
Contaminated food and drink are common sources for the introduction of infection into the body.