World Zoonoses Day: Raising awareness of animal human infectious diseases

Syllad | The Rising MeghalayaJuly 6, 2023

The “World Zoonoses Day” is being celebrated every year on the 6^th July to spread awareness amongst the peoples about zoonotic diseases and its impact on both human & animal health. It is celebrated in order to commemorate Louis Pasteur (French Biologist) who first administered Rabies vaccine to human bitten by a rabid dog (Joseph Meister) on 6^th July 1885 which not only prevented him from getting Rabies but also save his life. Therefore, the first world zoonoses day was celebrated on the 6^th July, 1885. The theme for this year is ‘One world, one health: Prevent zoonoses’.

It is also celebrated to a build a bridge (co-operation) between Public health experts, Veterinarians, Medicos and other stakeholders to find a solution to prevent and control zoonotic diseases and their impacts on both animal and human health (One Health approach). On this day many events like workshops, trainings, conferences, public lectures, seminars, awareness to public, enhanced surveillance, diseases screening, animals vaccination and welfare activities, etc are carried out.

The team “Zoonoses” refers to those infectious disease which are naturally transmitted between vertebrate animals and man with or without on arthropod intermediate. Dr. Rudolf Virchow (German Pathologist) is the father of Zoonoses and coined the term “Zoonoses” which indicate an infectious disease that is spread between animals and humans during his study on Trichinella Spiralis (Round worm) in swine in 1880. Zoonotic disease can range from a mild influenza like symptom to a severe illness even death.

Since the start of civilization, man is closely associated with animals either as food animals, companion animals and also as pack animals there is always a connection between man and animals. Dr. Jacob Nufer (Swiss Veterinarian) performed the first Caesarian section on a living woman which is still widely used to deliver human babies till date throughout the world. But in spite of all these relationship, many obstacles came in between, of which zoonoses pose a major threats to a man. Right from biblical times, plague was considered as one of the zoonoses which killed over 23 percent of human in Europe (1898) in one sweep including many other diseases like Rabies and Tuberculosis. Even in India, many zoonoses like Rabies, Tetanus, Tuberculosis (T.B), Salmonellosis, etc still pose a threat to peoples. In recent times, India also had experienced the outbreak of many zoonoses like Nipah Virus infection, Ebola virus infection, Corona virus (Covid 19), bird flu, swine flu, etc which causes both mortality and economic loss. Animals always have an important role in zoonotic infections and peoples need to be aware of it. It can originate from wild animals or even come from pets and farm animals. More than 60% of infectious diseases that affects humans are zoonotic. Zoonoses is a global threats to the world including India which causes socio-economic losses, financial losses, high fatality rate, poor animal health and low animals production (Farmer loss).

There are many types of Zoonoses and it can be classified accoding to its;-

(i) According to causative agents viz. Viral: caused by virus (Bird Flu, Ebola virus disease, Dengue Fever, Japanese Encephalitis, Nipah virus disease, Rabies, New Castle Disease, H1N1 virus/Swine Flu, etc.

Bacterial: caused by bacteria (Anthrax, Brucellosis, Cat scratch disease, Leptospirosis, Plague, Tuberculosis, Colibacillosis, Tetanus, Yersiniosis, etc)

Rickettsial: caused by rickettsia(Q-fever, Scrub Typhus, Rickettsial pox, Siberian tick Typhus, etc)

Mycotic: caused by fungi (Dermatophytosis, Sporotrichosis, Aspergillosis, Candidiasis, etc)

Prion: caused by prions(Bovine Spongiform encephalopathy – BSE)

Protozoa: caused by protozoa(Amoebiasis, Toxoplasmosis, Giardiasis, etc)

Helminthic: caused by helminths/worms (Taeniasis, Cysticercosis, Ascariasis, Filariasis, Fascioliasis, Schistosomiasis, etc)

Ectoparasitic: caused by ectoparasites (Scabies, Tungiasis, etc)

(ii) According to Reservoir host viz

Anthropo-zoonosis – diseases transmitted from animals to man e.g Anthrax, Cat scratch fever, Q-fever, Brucellosis and Rabies, Tuberculosis (Bovine & Avian)

Zoo-Anthropo zoonosis – diseases transmitted from man to animals e.g Tuberculosis (human), Measles, Infectious Hepatitis, Trichophyton rubrum infection.

Amphixenosis – diseases maintained/shared in both man and animals and be transmitted in either way e.g Salmonellosis and Staphylococcosis.

(iii) According to mode of transmission viz.

Direct zoonoses – Transmitted from one infected host to another e.g Ringworm, Scabies, Leptospirosis, etc

Cyclo zoonoses – Infections which requires more than one lost e.g Taeniasis

Metazoonoses – Infections biologically transmitted by invertebrate vector (Lice, Mites, flea, flies, mosquitoes, ticks, bugs, cyclops, etc) e.g plague, yellow fever, filariasis.

Saprozoonosis – Disease which requires Vertebrate hosts as well as non-animal sites (like soild, bird dropping, plant materials, etc) e.g Aspergillosis, Histoplasmosis.

(iv) According to principal hosts involved and occupation types. (Zoonoses of Veterinarians, pet handlers/owners, wildlife workers, Farmers, Abattoir workers, Health workers, etc) and also as Food borne and water borne zoonoses.

Some factors which favor spread of zoonoses include ecological changes, man-made disasters, natural disasters, environmental pollution, industrialization, increased population, socio-cultural changes, sudden change of food habits in humans, anthropological changes, increased human movements, handlings animal by-product and wastes, increased in animals trade, illegal trade of animals and its products, trans boundary illegal animal trade, increased in density of animal population in a particular areas, uncontrolled pets breeding, loose movement of exotic pets, transportation of virus infected vector, indiscriminate use of antibiotics in both humans and animals especially food animals, antibiotics resistance, multi drug-resistant microbes, improper garbage control and sewage disposal, close proximity between humans and animals, and many others.

Different modes of transmission of zoonoses agents:-

Direct contact e.g Scabies. Dermatophytosis
Indirectly through food, water and environment such as ingestion of milk (Brucellosis), meat (Taeniasis, Trichinellosis), fish (Vibriosis, Diphyllobothrium latum infection), poultry (Salmonellosis), water (Amoebiasis, Giardiasis, Shigellosis), Inhalation (Anthrax, Bird flu,H1N1 flu, Tuberculosis, SARS), Animals bite (Cat scratch fever, Rabies, rat bite fever, Sporotrichosis), Arthropods bite (Japanese Encephalitis, Plague, Scrub typhus, yellow fever, Filariasis, Kyasanur Forest Disease), Intrauterine/Transplacental : e.g Tetanus, Melioidosis.
Through intermediary species.

Control measures of Zoonoses

Blocking the transmission
Controlling the reservoir of infection
Vector control measures
Practice good hygiene and sanitary measures.
Regular Immunization/Vaccination of target population.
Regular worms control programme
Regular check up and screening of diseases of pets, livestocks.
Prompt diagnosis and treatment of positive clinical cases – Prophylaxis (Sero & Chemo).
Zoonoses control measures and prevention to be made aware to farmers, pet owners, health workers.
Health Education and Awareness Programme for livestock farmers, pet handlers, pet owners, Veterinarians, Public health workers, butchers, School children, elders, immune compromised persons.
One health approach/concept (Animal Health, Human Health, Environment Health)
Inter relationship between different stake holders.
Passing of Legislation & Public Health laws in controlling the zoonoses.