While some debate the ethics of slaughtering and consuming caught animals, the link between wildlife markets in Wuhan and the coronavirus outbreak has shown that doing so in sanitary conditions is unquestionably important, Duncan Smith writes.
One of the most magnificent achievements of the human race was the eradication of smallpox. Like coronavirus, smallpox is a highly contagious viral disease passed from human to human, and outbreaks of smallpox have been fatal in about 30 per cent of cases.
The disease often disfigured, and even blinded, its survivors. The last recorded case of natural infection was in 1977, and for the last 43 years, the world has been blissfully free of the deadly disease.
Two stocks of the virus remain in laboratories in the United States and Russia, and there is intensive debate as to whether scientists should destroy them to remove this virus finally from the face of the earth. Humankind eradicated smallpox by isolating infected people and vaccinating people at risk of exposure, even though no treatment for smallpox was ever discovered.
Smallpox remains the only disease humans have ever totally eradicated. This was possible for one simple reason – the only reservoir for this virus was people, and breaking the transmission cycle could isolate the disease. Policymakers and scientists can apply this to other human transmitted disease too. Polio is likely to be the next disease eradicated, and much of the problem for this disease lies in vaccinating people in remote or dangerous areas of the world.
Unfortunately, for many other viruses that infect humans, the situation is more complex and diseases more difficult to control. These viruses are not carried exclusively in the human population, but also by animals. These so-called ‘zoonotic’ viruses can cross the species barrier and infect humans.
Ebola virus made the news several times in the last few years following outbreaks in parts of Africa, and is a good example. It occurs in some species of bats, and scientists suggest that they could be the natural reservoir of the virus. The virus can also infect other animals, including non-human primates.
Transmission to humans can occur when a person has contact with bodily fluids such as the blood or secretions of infected animals. Once infected, a person becomes highly contagious and can rapidly spread the disease through their own blood or bodily fluids.
Given that bleeding is one of the main symptoms of infection, spread of the virus can be rapid and extensive. Early vaccine trials have shown good results in limiting the spread of outbreaks, but in contrast to smallpox, it is unlikely these diseases will ever be eradicated, because of the natural presence of the virus in animals. It means that there will always be the possibility of the disease erupting from nature in the future.
Street markets in Asia are either ‘wet’ or ‘dry’, because the floors of some markets are often literally wet from melted ice used to keep items fresh, as well as from the water used to wash away blood and other materials. While pre-slaughtered items are available, in many wet markets live animals are also for sale. This can include live chickens, ducks, frogs, reptiles, fish and shellfish. Some wet markets also sell captured wild animals, including endangered species, for consumption.
Sellers may slaughter animals on site, creating a witches brew of blood, bodily fluids, and feces all in publicly accessible areas. Evidence is emerging that coronavirus could have come from a wet market, but it is unclear which animal or animals were its original hosts.
Importantly, this has happened before. Severe acute respiratory syndrome (SARS) virus may also have originated through the sale for consumption of civet cats in wet markets.
Few things can divide people as much as debate over what is appropriate to eat. The issue is a complex one. Culture, religion, history and social environment all influence such views. While some religions have well defined dietary restrictions, such as the prohibition on eating pork for Muslims and Jews, or beef for Hindus, other religions or belief systems have few if any prescriptions.
Culturally, dogs and cats are pets in many parts of the world, but they can be a part of the menu in other parts. Similarly, there is strong sentiment against the hunting of whales for food in many parts of the world, while some countries strongly believe these animals are an historic and legitimate part of their diet.
Nevertheless, for most developed countries there is a sharp divide between animals reared for consumption, and animals caught for consumption. Even for marine animals, most developed countries now farm their seafood rather than fishing it.
For many countries, however, the divide between reared and caught is much more blurred, and this can bring people into potential contact with dangerous zoonotic viruses. It is essential that this boundary is clearly and sharply defined.
If animals caught in the wild are to remain on the menu, they must be sustainably farmed, humanely killed, and safely butchered.
Allowing the mixing of wild-caught animals with domestic animals and butchery in unsanitary conditions creates the danger that one man’s meat could become the whole world’s poison.