In early February of this year, The Lancet alerted the world to the latest strain of HXNX avian influenzas, commonly known as bird flu, currently circulating in China. The culprit this time: H10N8. In case you are keeping track, this type joins a rapidly growing list of avian influenzas that infect humans: H5N1, H7N9, H7N2, H7N3, H7N7, H9N2 and H10N7. H10N8’s first recorded manifestation was in a 73-year-old feverish woman who was admitted to the hospital on November 30th, 2013. Only a short time later, her organs started failing. Nine days after her illness began, she was dead. While the woman’s already existing chronic medical conditions, which included hypertension, coronary heart disease, and myasthenia gravis, possibly contributed to her death, scientists found “overwhelmingly dominant” numbers of the virus in tracheal specimens, indicating its role in her quick demise. Worse still, Chinese authorities have detected another case of H10N8 in January of this year.
The woman’s sudden death and the virus’ possible spread are not the only alarming facts of the story: four days before the first victim reported symptoms, she visited a live poultry market. While a later follow-up to the market detected no viral specimens, live poultry markets have long been a source of concern for public health professionals. As has been suggested by researchers inside China and out, and recently given intellectual weight by Perez and Garcia-Sastre, live poultry markets are probably the most important contributor to the evolution and transmission of avian influenza strains. In its paper entitled “Live Food Markets: Reducing the Risk of Influenza Virus from Animals,” the World Health Organization states that “avian influenza viruses…can be transmitted from infected animals to humans during handling and slaughtering in wet markets. It is therefore important to limit…close contacts between animals and humans in wet markets.” The weight of this evidence led Vincent Racaniello, Ph.D., a renowned virology expert at Columbia University, to posit a logical question:
Given their role in transmitting new viruses from animals to humans, I wonder why live poultry markets are not permanently closed.
Such a query brings us to the initial thrust behind zoning: public health. As Howard Frumkin points out in his landmark book Urban Sprawl and Public Health, in its earliest incarnations in late-19th Century Germany, zoning was first used to protect the well being of citizens by cordoning off slaughterhouses from residential areas. Unfortunately, zoning has not always gone hand-in-hand with improved health outcomes in a population. More recently, over-eager zoning ordinances have been linked to obesity prevalence through their disapproval of vertical mixed-use areas, where residences, shops, and other purposes often coexist in a single building, in favor of suburbanization. As Frumkin writes, America’s obesity epidemic “has not ‘happened’ to us.” Food intake and inactivity are at the heart of its spread, and zoning is culpable in at least the latter. Zoning’s role in drastically decreasing density and walkability in new and existing developments over the past century has “left us…unable to walk from homes to offices or shops.” In essence, the built environment compelled us to be inactive.
In light of these excesses and the latest news out of China, zoning’s original purpose and success is more relevant now than ever: safeguarding the health of a city’s citizens. In addition to promoting daily exercise, proper zoning can also have an impact on epidemic outbreaks, and the stakes are high. As well as being the most populous country in the world, in the last two decades China has been a global nexus of viral outbreaks. Arguably the most serious one occurred eleven years ago: SARS coronavirus. In late 2002, an unheard-of zoonotic pathogen emerged and started circulating in Guangdong Province in southern China. Within months, it had reached Hong Kong and its airports and spread like wildfire. By the time it was finally contained, the newly discovered virus had infiltrated over 37 countries and infected over 8,000 people, boasting a 9.6% fatality rate between November 2002 and July 2003.
While a globally devastating outbreak was prevented that time, with every passing year, China is more cosmopolitan than ever. Consequently, domestic viral outbreaks continue to harbor great transmissive potential, nationally and internationally. For these reasons and in the face of continuing bird flu scares, there is ample justification to consider changing zoning in large urban areas to disallow live poultry markets within municipal boundaries.
Some city governments have admittedly begun to realize this. For instance, Shanghai this year ordered the closure of all 117 live poultry markets in the city from the end of January until April 30th, all in order to stave off bird flu(s). The city plans to keep this restriction in place for the next five years, and reexamine its policies then. Other cities, such as Guangzhou, have begun to formulate new regulations regarding live poultry markets, and undertake regular disinfections.
Still, both of these cities have been loathe to entirely close these markets, largely due to popular opprobrium. As the WHO points out, for many citizens, food markets remain “the main source of affordable food, including fresh produce” and are an established economic and social sphere in the city fabric. Indeed, in an era where food safety remains a top concern for many Chinese, wet markets are notable for allowing customers to validate the freshness of food firsthand.
Thus, while these new city ordinances all recognize the threat live poultry markets present regarding zoonotic viral outbreaks, they are at most temporary stopgaps. In essence, a resolute decision lies hostage to the necessity of balancing dissenting, legitimate concerns: on the one hand, safeguarding distribution centers for fresh, low-cost food, while on the other, minimizing future public health threats. Only time will tell whether the decisions made were enough to prevent a wider outbreak.