When we talk about zoonoses we mean any type of disease that an animal can spread to a human being There is also another type of reverse zoonosis. This is anthropozoonosis, which is when a human being infects animals with a disease.
In this article we will refer strictly to zoonoses, since there are many diseases that animals of all kinds can infect us: wild and domestic.
If you are interested in the subject, continue reading our site and find out what Zoonosis is about with a complete definition and some examples:
Definition of zoonoses
Zoonoses are diseases or infections that a vertebrate animal can naturally transmit to humans.
Of the 1,415 known human pathogens, 61% are of zoonotic origin. Pathogens can be: bacteria, viruses, fungi and parasites. The definition of the word zoonosis comes from two Greek words. Zoo, which means: animal; and nosis, which means: disease.
There are two types of zoonoses: direct and indirect.
Direct and indirect zoonoses
- The direct zoonosis are those diseases spread directly from animal to animal, or from animal to human throughair (influenza), or stings or saliva (rabies).
- The indirect zoonosis is one that can be transmitted by a so-called vector, which is usually an intermediate animal that carries the disease pathogen.
The main types of zoonoses
There are 5 types of zoonosis: Prionic, Viral, Bacterial, Fungal and Parasitic.
Prion zoonosis
It happens when an abnormal prion protein causes neurodegenerative processes in animals or humans.
The most famous example is bovine spongiform encephalopathy (mad cow disease).
Viral zoonoses
The disease is caused by viruses transmitted by the animal. The most important ones are:
- Ebola
- Rage
- Zika
- Bird Flu
- Hantavirus
- Yellow fever
- Nile Fever
Bacterial zoonoses
Illnesses are caused by transmitted bacteria. Some of the most relevant are:
- Bubonic Plague
- Tuberculosis
- Brucellosis
- Carbuncle
- Salmonellosis
- Tularemia
- Leptopyrosis
- Fever Q
- Cat-scratch disease
Other types of zoonosis
Fungal zoonoses
They are caused by fungi and spores spread by carrier animals. The most important ones are:
- Tub
- Histoplasmosis
- Cryptococcosis
Parasitic zoonosis
They are diseases caused by parasites that live inside animals. Frequently the contagion occurs by consuming meat or fish that have not been cooked correctly and are contaminated by these parasites. Some of the most important are:
- Trichinosis
- Teniasis
- Toxoplasmosis
- Anisakis
- Amebosis
- Hydatidiasis
- Sapoptic mange
- Lesishmaniasis
- Echinococcosis
- Diphyllobothriasis
The hydatid cyst
The hydatidiasis produces the hydatid cyst. This cyst can adhere to any major organ: lungs, liver, etc.; and reach sizes well above an orange.
This disease is complex, since for its complete development it requires two different subjects or hosts. The first host is the one that carries the worm or adult tapeworm, and whose eggs are expanded with the animal's feces (usually a dog). These faeces contaminate plants consumed by herbivores, and tapeworm eggs develop in the duodenum of the new host (often sheep). From there they pass into the bloodstream and adhere to some organ, where the larva creates the dangerous cyst, which can be fatal.
Humans often contract this disease by eating poorly washed lettuce, or any vegetable that grows at ground level and is eaten raw.
