How illegal wildlife trade fuels spread of zoonotic diseases
The world’s emerging infectious diseases such as Ebola, Covid-19 and Lassa fever have one thing in common: they are zoonotic.
This means they originate from animals before they spill over to humans.
At the heart of this is illegal wildlife trade and destruction of wildlife habitats, which increases chances of direct contact between humans and wild animal species.
“Increased consumption of wildlife and wildlife products, coupled with the wanton destruction of wildlife habitats has destroyed natural barriers that exist between humans and wild animals,” says Kaddu Sebunya, CEO, African Wildlife Foundation.
Human encroachment into wildlife habitats through activities such as poaching, deforestation, consumption of game meat act as a catalyst to the spread of disease from animals to people.
Between 1980 and 2000, United Nations reports over 100 million hectares of forest land has been converted into agricultural land.
The shrinkage of the buffer between humans and animals is forcing close contact between the two species and fanning the spread of zoonosis.
Statistics by the United Nations show an estimated 60 per cent of all infectious diseases in humans are zoonotic.
Similarly, 75 per cent of all emerging infectious diseases originate from animals with at-least one new disease emerging in humans every four months.
Maarten Hoek, a veterinarian and epidemiologist, explains that animals serve as reservoirs for viruses, bacteria and parasites.
“The pathogens occur naturally in animals without causing any disease in them, but can turn fatal once they spill over to other species,” he says.
Some commonly known zoonotic diseases include malaria, anthrax, hepatitis E, swine flu, rabies and ringworms.
While studies are yet to give conclusive answers on its actual source, the new coronavirus, a zoonotic disease with origins in Mainland China, is suspected to have originated from bats and passed to humans through another animal possibly the pangolin, the world’s most trafficked mammal.
The virus spillover occurred in the country’s wet markets where fresh meat and live animals caught from the wild or raised in farms are sold.
“Prior to being consumed as meat, these animals are not tested for diseases, so this is an easy way for pathogens to enter the human body and may result in zoonotic diseases,” adds Hoek.
The markets are poorly regulated and animals are transported from across regions and housed together in unhygienic conditions.
Another deadly infectious disease, Ebola, has been linked with bats and initially passed to humans through contact with blood, secretions and other bodily fluids of infected bats.
Lassa fever, currently endemic in Nigeria, a viral haemorrhagic fever is transmitted to humans through contact with bodily fluids of infected rats.
Trade in wildlife has led to significant decline in animal populations over the past decades.
Wildlife and their products are in demand by people who use them as food, medicine and status symbols.
Trade in wildlife is not only accelerating the rate of species extinction, but also denuding ecosystems of important organisms.
Restoring biodiversity, Hoek says, could be a solution in curbing spread of zoonotic diseases. “If you have animals genetically similar in one space, and a virus emerges, it will quickly spread and affect all animals.
But if you have a wide variety of animals, a virus that is adapted to affect specific hosts, will not spread to other species,” he says.
The current Covid-19 pandemic, conservationists says, is an opportunity to learn crucial lessons on how to handle wildlife.
China has alrady banned trade and consumption of wild animals. Sebunya, however, notes it is going to take more than just a ban to undo the harm caused by illegal wildlife trade on both human health and nature.
“The Covid-19 outbreak provides a window to address this, however, it should not be used to prescribe global wildlife trade policy. Typically, prohibition does not deter all traders in marketplaces.
Traders would be motivated by financial profits, with an increased risk of trade being controlled by organised crime,” he says.
He adds that bans may not be effective in stigmatising consumption, especially in places where products are socially desirable; thus, demand for many wildlife products will persist.
The risk of spread of zoonotic diseases is rife in rural communities in Africa that rely on bush meat for food.
Sebunya says combatting illegal wildlife trade will require governments to bolster animal protection efforts within countries and across borders and educate people on the need to change wildlife consumption behaviours.
The ripple effect Covid-19 is likely to have on conservation is huge. Communities that live around protected areas and rely on tourism to earn a livelihood are staring at lost incomes.
Due to job losses and pay-cuts, many rural families that rely on remittances from relatives are uncertain about the ability to meet basic needs.
Out of desperation, some may turn to game meat consumption to feed their families.
“This might leave them vulnerable to exploitation from poachers running sophisticated illegal wildlife trade rings who might recruit them to poach big game,” adds Sebunya.
As tourism revenues shrink, protected areas that rely on these incomes to run their operations are likely to cut down on their patrols leaving loopholes that could be exploited by poachers.
On the brighter side, intense reduction in air and sea transport will result in a decline in international trade in endangered species and their products.
However, that will not entirely deter illegal wildlife trade since the demand for products is still there.