Zoonoses are diseases that are transmitted from animals to humans and vice versa. The pathogens involved can be bacteria, viruses, fungi or even parasites. The transmission of these diseases occurs either directly, during contact between an animal and a human being, or indirectly through food or through a vector or the environment. Their severity and symptoms vary greatly depending on the disease and the person infected. The management depends mainly on the pathogen involved.

The term zoonosis comes from the Greek words zoon which means “animal” and we are which means “disease”. A zoonosis is a disease transmissible from an animal such as a dog, cow, hen or pig, to humans and vice versa. According to the World Organization for Animal Health, 60% of human infectious diseases are zoonotic, and it is estimated that zoonoses are responsible for at least 2,4 billion cases of human disease each year and 2,2 billion million deaths.

Bacterial zoonoses 

• to fish;
• salmonellosis;
• la leptospirosis;
• listeriosis;
• brucellosis;
• anthrax;
• cat scratch disease;
• Lyme disease;
• tetanus;
• tuberculosis ;
• campylobacteriosis.

Viral zoonoses 

• rabies;
• bird flu ;
• chikungunya;
• Dengue
• Lassa fever;
• hepatitis A;
• herpes virus B;
• Ebola virus disease.

Parasitic zoonoses 

• toxoplasmosis;
• tapeworm;
• the ascaridose;
• la leishmaniasis;
• sleeping sickness; 
• malaria; 
• the trichurose.

Fungal zoonoses 

• l’aspergillose ;
• candidiasis;
• la coccidioïdose.

Prion zoonoses

• mad cow disease, the cause of Creutzfeldt-Jakob disease.

The modes of transmission of zoonoses to humans are varied. Indeed, these can be transmitted:

• directly during contact between an animal and a human being as is the case with the rabies virus or that of avian influenza;
• indirectly through the consumption of animal products such as eggs, milk or meat as is the case with salmonella, toxoplasm, anisakis parasitic worm, etc. ;
• through a vector: insect, arachnids etc. ;
• through the environment: water, soil, etc. ;
• from one infected individual to another.

Zoonotic pathogens can spread to humans through any point of contact with domestic, agricultural or wild animals:

• markets where meat or wild animal by-products are sold present a particularly high risk due to the high number of new or unrecorded pathogens known in certain populations of wild animals;
• agricultural workers in areas with heavy administration of antibiotics to livestock may be at increased risk of pathogens resistant to current antimicrobial drugs;
• people living near wild areas or in semi-urban areas where the number of wild animals is higher are at risk of contracting zoonoses transmitted by animals such as rats, foxes or raccoons;
• Urbanization and destruction of natural habitats increase the risk of zoonoses by increasing contact between humans and wildlife.

To limit any exposure to zoonoses, simple preventive measures should be adopted such as:

• hand washing;
• “through” cooking of food;
• the fight against mosquitoes.

• the digestive system: salmonellosis, campylobacteriosis etc. ;
• the respiratory system: avian flu, SARS etc. ;
• the liver: hepatitis E virus;
• the nervous system: rabies virus (lyssavirus);
• or several organs at the same time.

Their severity in humans can vary greatly depending on the disease itself, the pathogen responsible may be more or less virulent, and depending on the infected person who may be particularly sensitive to these pathogens. This is the case for people with fragile immune systems such as:

• immunocompromised people;
• people on immunosuppressive therapy;
• young children;
• the elderly ;
• pregnant women.

• disinfection of wounds;
• antifungal ointments;
• anti-infective;
• specific antibiotic therapy (amoxicillin, cephalosporin, doxycycline, azithromycin, ciprofloxacin, rifampicin, gentamicin, etc.).