Why are humans susceptible to animal diseases?

The world is struggling with a new strain of corona virus, thought to come from wildlife. Before that, many diseases also originated from animals.

Over the past two weeks, Chinese police have raided many families, restaurants and markets across the country, arresting nearly 700 people for violating a ban on the capture, sale or consumption of wildlife.

The crackdown seized nearly 40,000 animals including squirrels, ferrets and wild boars. This shows that Chinese people's habit of eating wildlife and using animal parts for medicine could not disappear overnight, although the corona virus outbreak is still serious.

The habit of eating wild animals "raises" the virus

According to Reuters, the shop owners selling donkeys, dogs, deer, crocodiles . said they plan to return to business as soon as the market reopens.

"I will sell again when the ban is lifted. People like to buy wildlife. They buy to eat or give gifts because it is very easy to sell and gives a reputation," said Gong Jian, owner of an animal store. Wild online in Inner Mongolia autonomous region, said.

Recent research suspects, though not specifically proven, that corona virus is transmitted to humans from bats through pangolin. It is a scaly small mammal that is highly appreciated in traditional Chinese medicine.

Vials of solid pickled wine are stored on a snake farm in Zhejiang, China.(Photo: Reuters)

Earlier, the earliest detectors came from Wuhan's seafood market, which sells bats, snakes, civets, and many other wildlife. China temporarily closed all such markets in January, warning that eating wild animals poses a major threat to public health and safety.

However, according to Wang Song, a zoologist at the Chinese Academy of Sciences, it may not be enough to change the tastes or habits deeply rooted in the culture and history of the soil. country."In the eyes of many people, animals live for humans, rather than sharing the earth with humans , " said Wang Song.

The corona virus outbreak, which has killed more than 1,600 people in China, sparked a debate about the use of wildlife as food and medicine. Many academics, environmentalists and people of the country have joined international conservation groups, calling for a ban on the wildlife trade.

However, a part of Chinese still likes to eat wild meat because they believe it is good for health . Many wildlife markets, such as those in Wuhan and their online businesses, largely illegal, remain.

How do animals spread diseases to humans?

Over the past 50 years, a range of infectious diseases has spread rapidly from animals to humans.

The 1980s HIV / AIDS crisis stems from the great ape; the 2004-2007 avian influenza pandemic originated from birds; swine flu in 2009 was caused by pigs. Severe acute respiratory syndrome (SARS) comes from bats, mediated by civets; while bats also caused the Ebola pandemic.

Humans are always infected by animals. In fact, most new infectious diseases come from wildlife. But it is worth mentioning that the changing environment is accelerating this process, the factors of city life and the increasing demand for international tourism make these diseases appear and spread faster.

Bats are thought to be the source of many infectious diseases.(Photo: SCMP).

Most animals carry a range of germs - bacteria and viruses that can cause disease. The ability of the pathogen to evolve depends on infecting new hosts and jumping to other species.

The new host's immune system tries to destroy the pathogen, that is, both the new host and the pathogen, are trying to find new ways to destroy each other.

For example, about 10% of infected people died in the SARS epidemic in 2003, compared to less than 0.1% from the common flu.

Environmental and climate change are changing and destroying the habitat of animals, changing the way they live, inhabit and feed. Even human lifestyles have changed, 55% of the global population now lives in cities, up from 35% 50 years ago.

And these larger cities are expanding the space for wildlife such as rats, pandas, squirrels, foxes, birds, jackals, monkeys, etc. to live in parks and gardens, eating food that people leave behind. .

Normally, wild animals are easier to adapt to urban habitats than in nature because of the abundant food supply, making the city space an ideal place for pathogens to progress. chemistry.

City people and animals live together.(Photo: Gettyimages).

Which group of people is most at risk of spreading the disease?

New diseases in new hosts are often more dangerous, which is why any new disease occurring is of great interest. Some groups are more susceptible to new diseases than others.

Poor city dwellers often have to do jobs such as cleaning and sanitation, easily meeting the sources and pathogen carriers. They may also have a weaker immune system due to poor nutrition and less access to fresh air or unhygienic conditions. And if they get sick, they may not be able to afford adequate medical care.

New infections are also more likely to spread faster in large cities because of the large population, less fresh air and the same surface contact.

In some cultures, people also eat certain types of wildlife. This is also the reason why they are more susceptible to infectious diseases.

Governments tend to treat each emerging infectious disease as an independent crisis, rather than recognizing that they are a sign of how the world is changing. The more people work to change their environment, the more likely they are to disrupt ecosystems and create opportunities for new diseases to appear.

Only about 10% of pathogens in the world have been recorded. Therefore, more investment is needed to identify the remaining pathogens and which animals are carrying those pathogens. For example, we need to know how many mice are in London and what pathogens they carry.

Many city dwellers are satisfied with living with wildlife in the same space, but people should also realize that some of them can be harmful.

Therefore, it is important to keep an eye on whether new animals are coming, are people killing or eating wildlife, or bringing them from nearby areas for sale at the market. .

Improving sanitation, waste treatment, and disease control are all ways to help prevent disease from spreading and spreading. That helps change the way we manage the environment and the way people interact with it.

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