At one time, an outbreak of a disease in a remote village would probably burn itself out quickly, but today that same virus has the potential to become a global pandemic, says York Professor Harris Ali, co-editor along with York Professor Roger Keil of the new book, Networked Disease: Emerging Infections in the Global City (Wiley-Blackwell).
The book deals with how, through the intensified interactions of humans, and the speed of travel and enhanced mobility, a virus could quickly spread to a major urban centre and from there become part of a global network of cities, says Ali.
There is an increasing interconnection between disparate places of the world, urban centres and previously remote areas. Coupled with the speed of travel and environmental pressures, there are particular challenges today that weren't present several decades ago regarding the spread of infectious diseases. The 2003 outbreak of Severe Acute Respiratory Syndrome (SARS) in Toronto and elsewhere is a case in point.
“The spread of SARS vividly demonstrates that globalization means that infectious disease can no longer be thought of as a problem limited and localized to the developing world, as the disease spread amongst some of the more advanced and developed cities of the contemporary world – Toronto, Singapore, Hong Kong,” says Ali, an environmental sociologist and professor in York’s Faculty of Environmental Studies.
As such, the spread of SARS demonstrates how increased social, technological and ecological connectivity, which essentially forms the backbone of globalization, has implications for disease diffusion and the response to that diffusion.
Networked Disease: Emerging Infections in the Global City, part of the Wiley-Blackwell Studies in Urban and Social Change Book Series, is a collection of writings by leading experts and newer researchers on the SARS outbreak and its relation to infectious disease management in progressively global and urban societies. It presents original contributions by scholars from seven countries on four continents and focuses on the ways pathogens interact with economic, political and social factors, ultimately presenting a threat to human development and global cities. The book employs an interdisciplinary approach to the SARS epidemic to demonstrate the value of social scientific perspectives on the study of modern disease in a globalized world.
“It acts as an important intervention into a vital international debate on how to understand and prepare for the potentially pandemic spread of infectious disease, such as SARS and avian flu, through a system of accelerated and generalized, urban-based transportation networks,” says environmental studies Professor Keil, director of the City Institute at York and co-editor of The Global Cities Reader and the International Journal of Urban and Regional Research. “The world has shrunk and the speed by which people may be affected by disease has increased.”
Right: Roger Keil
The new internationalized and networked cities are the hubs of both disease outbreak and control. The role of cities in the spread of infectious disease needs to be better understood, says Keil, author of Los Angeles: Urbanization, Globalization and Social Struggles and co-author of Nature and the City: Making Environmental Policy in Toronto and Los Angeles. The ability of municipal and local political actors to fight against globally spread disease is crucial. To that end, the World Health Organization (WHO) is now working with urban actors so they may recognize their role in monitoring and fighting against infectious disease.
This is particularly important as the chance of contact with certain viruses, often through animals, is increasing. Globalization has meant technological and economic activities are impinging on previously untouched ecosystems at an unprecedented level and at the same time regulation is decreasing, says Ali.
“The implications of this is that what was in the past an untouched animal reservoir which hosts the viruses – viruses are often maintained in animal reservoirs before crossing over to human beings – is now more likely to be intruded upon by human beings, thus increasing the possibilities for disease diffusion through contact once the pathogen is able to genetically adapt so as to be able to survive in the human host,” says Ali, whose research interests involve the study of environmental health issues and the sociology of disasters and risk from an interdisciplinary perspective.
This can also happen when urban sprawl moves into previously untouched landscapes, increasing the chance of contact with certain viruses and animals. Ali points to Lyme disease transmitted by derr ticks as well as the interactions between palm civet cats, the reservoir for SARS, and human beings as examples.
Left: Harris Ali
The other problem for the spread of infectious disease, which the book details, is within urban environments. In Hong Kong, one of the ways in which SARS was transmitted environmentally was through vertically connected units in a modern apartment complex. A faulty drainage downpipe that connected washrooms, one above the other, was responsible for spreading the disease to people living in those units, says Ali.
In addition, slums in cities suffering from underdevelopment and colonial heritage, with their poor sewage and water infrastructure and crowded conditions, provide a good ecological niche for viruses to survive. Many of these slums occur in some of the world’s largest megacities, increasing the likelihood that a virus could again be spread through a globalized network of cities.
The book also argues that hospitals need to be looked at. The spread of SARS occurred mostly in hospital and health care settings. That means the environmental conditions of hospitals, including crowded waiting rooms and overworked staff, have provided suitable conditions for the viruses to spread. “The role of hospitals in global cities in the spread of infectious disease must therefore be an important consideration in dealing with future outbreaks,” says Ali.
On the upside, the book points to the unprecedented global reaction and response to SARS as highlighting the globalization of forces. This time the globalization allowed for an expansive networking of information and technologies. WHO was able to coordinate the sharing of clinical, epidemiological and virological data from scientists around the world in real time.
“This led to the discovery of the causative agent of the disease, the development of a case definition and the detailed structure of the genetic code of the virus within a record time, within months,” says Ali. “That’s something that would simply not have been possible in the past, before the advent of the global potential of the Internet.”
Networked Disease: Emerging Infections in the Global City was made possible through a research grant from the Social Sciences & Humanities Research Council of Canada. For more information about the book, click here.