Comment

China's complacency has led to this predictable coronavirus outbreak

China is well known for it's 'wet' food markets, which sell both dead and live meat products
China is well known for it's 'wet' food markets, which sell both dead and live meat products Credit:  South China Morning Post

The world had been warned repeatedly. Experts have said time and again from where and how the next deadly virus would emerge. And yet, here we are facing the reality we all knew was coming.

It began, quite predictably, at a crowded live animal market. A virus unknown to humans was lurking in a chicken, pig, or other local delicacy. Then came the spread to humans with zero immunity. With no test, vaccine, or proven medicine the epidemic is with us.

Epidemiologists are not yet in full agreement about the precise animal culprit for the coronavirus sweeping through China and beyond. But there is no doubt the outbreak originated from a local "wet" market selling dead and live poultry, pigs, camels and reptiles.

The outbreak resulted from an animal-to-human species jump – as do three of four new human infectious diseases epidemics. HIV/AIDS, Ebola, Zika, avian influenza (bird flu), as well as previous Sars and Mers coronavirus outbreaks all originated in animals.    

Most animal viruses are quickly eliminated by human defences. But it only takes one new viral strain and a vulnerable human host to be the catalyst for an entirely new disease outbreak.

Wet markets put a wide variety of live animals in close proximity to large numbers of handlers, sellers and customers. The resulting contact of humans with respiratory droplets, faeces or body fluids from live animals, or the carcasses or raw meat of dead animals each year provides millions – if not billions – of opportunities for new strains of coronavirus, influenza or other viruses to make their way into humans.  

If wet markets are such a threat to public health, why not ban them? The Chinese government tried this in 2013 when they closed wet markets in response to a deadly avian influenza outbreak. The banned wet markets were immediately replaced by potentially more dangerous black markets, with virtually no impact on the epidemic and massive economic losses.

More fundamentally, wet markets are an important source of affordable food for growing urban populations. And they are deeply embedded in the culture and economy for millions throughout China and other parts of Asia.

tmg.video.placeholder.alt L1LJb9Glav4

Making wet markets safer, while over time shifting consumer preferences to safer sources of meat, provides a sensible alternative to an outright ban.

Following the 2003 Sars outbreak, Hong Kong undertook a series of measures to strengthen the regulation of wet markets and their animal supply chains. Among the changes were regular disinfection, reducing faecal contamination, and more hygienic slaughtering. Consumers were also educated on safer handling of wet market purchases.

Measures to promote healthy food markets have been implemented in other countries, including Thailand, Vietnam and Bangladesh. Targeted surveillance of viruses with epidemic potential could track the effectiveness of such measures and has helped poultry producers in countries from North America to Asia to identify and cull poultry with highly deadly avian influenza.

The ecology of viruses, animals and humans make future outbreaks of new infections inevitable. The expanding web of risk factors – from population growth, greater demand for animal food, urban crowding, international travel, to global warming – will only accelerate this process.  

Traditional Chinese wet markets remain a threat to global health. China’s political and public health leaders must not fall into the cycle of short-lived commitments and long-term complacency following high-profile epidemics.

  • Dr Jonathan Quick is the author of The End of Epidemics and adjunct professor of global health at the Duke Global Health Institute

Protect yourself and your family by learning more about Global Health Security. And sign up to our weekly newsletter here

License this content