In 2019, Covid-19 emerged, which is considered one of the major medical catastrophic events in history. Coronavirus exposed human beings to the concept of Zoonoses or Zoonotic diseases. Suspected to be originated from a bat, coronavirus distressed human beings all around the world with high death tolls and huge economic loss.
Zoonotic diseases are infections caused by pathogens transferred from animals to humans or from humans to animals. More than 60% of pathogens known to humans are zoonotic. Direct zoonosis where a pathogen is transmitted from animal to human, can be through means of air, saliva, or bites.
Inter-species transmission of diseases is growing with a high population and increased contact between animals and human beings. The exploitation of wildlife in recent decades has shifted animals from wilderness to populated areas making humans more vulnerable to these infections.
How do Zoonotic diseases occur?
The occurrence of zoonotic disease can be influenced by various factors, including environment, host, and related human behavior. Let us more common causes contributing to Zoonotic diseases.
Farming: Farming, ranching, veterinarians, and animal husbandry involve close contact of animals with human beings. Working with these animals, especially chickens and pigs has contributed to a high risk of animal transmitted infections.
Contaminated food and water: With the rising demand for meat and dairy, food-borne diseases are easy to spread.
Pets: Pets carry a number of diseases. Dogs cats and horses are common domesticated animals that should be routinely vaccinated to resist any potential infections.
Deforestation and Climate change: Destruction of wildlife and rapid urbanization is a growing concern. Animals move from their natural habitat to populated areas and become carriers of diseases. Reducing biodiversity allows for small animals such as bats and rats to proliferate.
Wildlife Trade: Covid -19 was first identified in Wuhan China with intense wildlife trading activities. These wildlife markets are more potential to spread a risky virus with their closed spaces and increase animal-human contact.
Zoonotic diseases threatening human lives
Rabies: Rabies, a viral disease, is caused mainly by biting and scratching by an infected animal. Cats, dogs, monkeys sheep, and many more animals carry its pathogens. Symptoms like high fever, nausea, vomiting, and uncontrolled excitement are observed which can get more fatal at later stages. Rabies can be prevented through vaccines but there is no treatment currently available.
Bird Flu: It is spread through a bird-adapted strain H5N1 also known as avian influenza. It is spread through close contact with wild birds and domesticated birds such as chickens Between 2003 to 2020, more than 450 people died from bird flu. High fever, shortness of breath, muscle pain, and sore throat are some of the symptoms of this disease.
Anthrax: An infection occurring in the form of blisters on the skin, inhalation problems, fever, nausea vomiting, and abscess. It spreads through human contact with the bacterium Bacillus Anthracis which is often found in infectious animal products. Anthrax vaccination is recommended for people who work with animals or animal products.
Plague: Bubonic plague, pneumonic plague, septicemic plague, and sylvatic plaque are caused by Yersinia pestis, a pathogen carried by animals like rabbits, hares, rodents, and ferrets, goats, and sheep. This infamous disease led to millions of death in the middle ages in Europe.
Smallpox: This highly infectious disease is caused by variants of the Variola virus (VARV). Smallpox has been declared eradicated by World Health Organization.
Psittacosis (Parrot fever): Another zoonotic infection from the Chlamydophila psittaci virus. Birds like parrots, pigeons, sparrows, ducks hens, and many other bird species carry this infection. Severe pneumonia, spleen enlargement, severe headache, and even coma can be the result of this virus.
Trichinosis( Trichinellosis ): Caused by Trichinella type roundworms, this parasitic disease infects people eating undercooked meat like pork, boar, and dog meat. After being eaten, larvae released in stomachs migrating to muscle may cause symptoms like swelling, muscle pain, rashes, and inflammation in heart muscle and lungs.
Covid – 19: Severe Acute Respiratory Syndrome ( SARS-CoV-2) occurred in 2019 in China which led to millions of death around the world. This fatal disease is suspected to be transmitted from Bats. Common symptoms include cough, sore throat, and muscle pain. headaches, and in severe cases breathing problems with low oxygen levels in the human body.
Unsustainable Human Activity and rapid exploitation of wildlife make future generations prone to more frequent outbreaks of zoonotic diseases. Government policies with human action can prevent these outbreaks and protect lives.