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1. New Findings on Links between Urban Expansion and Viral Disease in Vietnam Offer Lessons for COVID-19

Author:
James H. Spencer, Sumeet Saksena, and Jefferson Fox
Publication Date:
04-2020
Content Type:
Commentary and Analysis
Institution:
East-West Center
Abstract:
The current COVID-19 pandemic, which started in Wuhan, China, underscores what the public health community has warned about for more than two decades—the risk of viral diseases capable of spreading from animal to human hosts. The first outbreaks of “bird flu” (highly pathogenic avian influenza—HPAI, subtype H5N1)—raised similar concerns 20 years ago, concerns that have persisted with the outbreak of SARS in 2002–2004 and COVID-19 today. A recent study compared information on infrastructure and other aspects of economic development in Vietnam with outbreaks of avian influenza. While this research focuses on avian influenza in Vietnam, the study of links between infrastructure characteristics and new and reemerging health risks has broad applicability, especially given the global importance of today’s rapidly expanding urban landscapes.
Topic:
Infectious Diseases, Urban, and COVID-19
Political Geography:
China, Asia, and Vietnam

2. Built-Up Area Change Analysis in Hanoi Using Support Vector Machine Classification of Landsat Multi-Temporal Image Stacks

Author:
Jefferson Fox, Duong Nong, Miguel Castrence, Tomoaki Miura, James Spencer, and Qi Chen
Publication Date:
10-2014
Content Type:
Working Paper
Institution:
East-West Center
Abstract:
Vietnam is experiencing one of the greatest urban transitions over the last two decades after the embankment of "Doi Moi" policy in 1986. The urban transition is vividly manifested in social, economic and physical aspects. While the urbanization can boost the industrialization and modernization goals of the country, it can cause adverse impact on natural environment as well as society and economy. To support a sound urban development plan, it is important that data and analysis on urban built-up areas are accurate and timely available. In this study, the Support Vector Machine Classification Algorithm (SVM) was applied to the multi-temporal image stacks of Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM) from 1993 to 2010 to quantify the changes of built-up areas over three time periods, 1993-2001, 2001-2006, and 2006-2010 and across twelve buffer zones. Our SVM classification algorithm has produced a highly accurate map of land use/land cover change with the overall accuracy of 95%. The study showed that most of the urban expansion occurred in the periods 2001-2006 and 2006–2010. The analysis was strengthened by the analysis of population census and other socio-economic figures. Through out this study, an implicit correlation between the urban growth, the trend of spatial expansion and other relevant geographic and socio-economic factors can be proposed. Result of this study would allow urban planners and decision makers to timely evaluate and adjust accordingly the urban growth and be aware of the sustainable usage of the invaluable natural lands and other environmental, social and economical problems.
Topic:
Economics
Political Geography:
Vietnam

3. Quantify Spatiotemporal Patterns of Urban Growth in Hanoi Using Time Series Spatial Metrics and Urbanization Gradient Approach

Author:
Jefferson Fox, Duong Nong, Tomoaki Miura, James Spencer, Qi Chen, and Christopher Lepczyk
Publication Date:
10-2014
Content Type:
Working Paper
Institution:
East-West Center
Abstract:
The year of 2010 was the first time in human civilization that the urban population had reached 3.5 billion people or crossed the 50% mark and continued to grow with no sign of slowing down especially for developing countries in Africa and asia (UN,2011). In 1800, only few percent of the world population lived in urban areas, but quickly increased to 14% in 1900 and then 30% in 1950 (platt,1994). Clearly, urban areas have become one of our primary habitats; therefore, urban sustainability is becoming more important than ever.
Political Geography:
Africa and Asia

4. Policy Implications for Prevention of Highly Pathogenic Avian Influenza Subtype H5N1 in Conjunction with Risk Factors in the Red River Delta, Vietnam

Author:
Jefferson Fox, Chinh C. Tran, John F. Yanagida, and Sumeet Saksena
Publication Date:
10-2014
Content Type:
Working Paper
Institution:
East-West Center
Abstract:
The challenge is to develop the vaccination program that is more successful in containing and preventing the Highly Pathogenic Avian Influenza subtype H5N1 from recurrence in the Red River Delta, Vietnam and reducing vaccination costs. This study addresses the tradeoff between the current policy which implements an annual two-round vaccination for the entire geographical area of the Delta and an alternative policy which involves more frequent vaccination in higher probability areas for the disease occurrence within the Delta. The ex-ante analysis framework is used to identify the location of higher probability areas for the alternative policy and evaluate the accuracy of the analysis. The efficacy and cost analysis of vaccination programs are then implemented for the tradeoff between the current and the alternative policies. The ex-ante analysis suggests that the focus areas for the alternative vaccination program include 1137 communes, corresponding to 50.6% of total communes in the Delta and mostly located in the coastal areas to the east and south of Hanoi. The efficacy and cost analyses suggests that the alternative policy would be more successful in reducing the rate of disease occurrence and the costs of vaccination as compared to the current policy.
Political Geography:
Vietnam and United Nations

5. Perceived Risk of Avian Influenza in Poultry Varies with Urbanization in Vietnam

Author:
Jefferson Fox, Melissa L. Finucane, Sumeet Saksena, Nghiem Tuyen, James H. Spencer, Nguyen Lam, Trinh Dinh Thau, Tran Duc Vien, and Nancy D. Lewis
Publication Date:
10-2014
Content Type:
Working Paper
Institution:
East-West Center
Abstract:
Highly pathogenic avian influenza (HPAI) is an important public health concern because of its potential to cause widespread morbidity and mortality in humans and poultry and associated devastating economic losses. In this study we examined how perceptions of and response to the risk of HPAI in poultry vary across communes/wards in the north of Vietnam at different levels of urbanization (rural, transitional, urban). We conducted a quantitative household survey with 1073 respondents. Results suggested that the perceived risk of HPAI in poultry was highest in transitional and rural settings. Respondents in these settings were more likely than respondents in urban settings to agree that the process of change (in urbanization, agricultural practices, or natural habitat) increased the likelihood of an outbreak of HPAI in poultry. Compared with others, respondents in transitional areas reported that they do less planning and perceive vaccines to be more effective, while respondents in rural areas reported less perceived ability to separate infected poultry from others. We also found that the inability to respond is not necessarily because of an inability to perceive change but because, rapid and extensive change poses different challenges for poultry management as communes move from rural to transitional to urban settings. Our results suggest that public and animal health campaigns could be tailored in a way that recognizes the needs of poultry raisers in different settings.
Topic:
Health, Infectious Diseases, and Urbanization
Political Geography:
Asia and Vietnam

6. Role of Urbanization, Land-Use Diversity, and Livestock Intensification in Zoonotic Emerging Infectious Diseases

Author:
Jefferson Fox, Duong Nong, Miguel Castrence, James Spencer, Sumeet Saksena, Nguyen Lam, Tran Duc Vien, Michael Epprecht, Chinh Tran, Melissa Finucane, and Bruce Wilco
Publication Date:
10-2014
Content Type:
Working Paper
Institution:
East-West Center
Abstract:
Emerging infectious diseases (EIDs) continue to significantly threaten human and animal health. While there has been some progress in identifying underlying proximal driving forces and causal mechanisms of disease emergence, the role of distal factors is most poorly understood. This article focuses on analyzing the statistical association between highly pathogenic avian influenza (HPAI) H5N1 and urbanization, land-use diversity and poultry intensification. A special form of the urban transition—peri-urbanization—was hypothesized as being associated with 'hot-spots' of disease emergence. Novel metrics were used to characterize these distal risk factors. Our models, which combined these newly proposed risk factors with previously known natural and human risk factors, had a far higher predictive performance compared to published models for the first two epidemiological waves in Viet Nam. We found that when relevant risk factors are taken into account, urbanization is generally not a significant independent risk factor. However, urbanization spatially combines other risk factors leading to peri-urban places being the most likely 'hot-spots'. The work highlights that peri-urban areas have highest levels of chicken density, duck and geese flock size diversity, fraction of land under rice, fraction of land under aquaculture compared to rural and urban areas. Land-use diversity, which has previously never been studied in the context of HPAI H5N1, was found to be a significant risk factor. Places where intensive and extensive forms of poultry production are collocated were found to be at greater risk
Topic:
Health, Infectious Diseases, and Urbanization
Political Geography:
United States and Asia

7. Crossing Borders, Changing Landscapes: Land-Use Dynamics in the Golden Triangle

Author:
Jefferson Fox
Publication Date:
11-2009
Content Type:
Working Paper
Institution:
The Cato Institute
Abstract:
Over the last half-century, public policy has affected land-use practices across the borders linking China, Thailand, and Laos. Political and economic reforms have facilitated labor mobility and a shift in agricultural practices away from staple grains and toward a diverse array of cash crops, rubber being one of the foremost. China has promoted the conversion of forests to rubber agroforestry in southern Yunnan—profitable for farmers, but a concern in terms of biodiversity and long-term viability. In Thailand, the response is at the other end of the spectrum as the government's concerns about land-use practices and watershed management have led to policies that dramatically constrain land-use practices and limit tenure rights. In Laos the future is not yet clear. Government policies provide weak support for both private land ownership and protected areas. In a global environment where national policy has such a dramatic effect on land use and land cover, the factors behind land-use change merit close examination.
Topic:
Agriculture and Economics
Political Geography:
China, Asia, Thailand, Southeast Asia, and Laos

8. Crossing Borders, Changing Landscapes: Land-Use Dynamics in the Golden Triangle

Author:
Jefferson Fox
Publication Date:
12-2009
Content Type:
Policy Brief
Institution:
East-West Center
Abstract:
Over the last half-century, public policy has affected land-use practices across the borders linking China, Thailand, and Laos. Political and economic reforms have facilitated labor mobility and a shift in agricultural practices away from staple grains and toward a diverse array of cash crops, rubber being one of the foremost. China has promoted the conversion of forests to rubber agroforestry in southern Yunnan--profitable for farmers, but a concern in terms of biodiversity and long-term viability. In Thailand, the response is at the other end of the spectrum as the government's concerns about land-use practices and watershed management have led to policies that dramatically constrain land-use practices and limit tenure rights. In Laos the future is not yet clear. Government policies provide weak support for both private land ownership and protected areas. In a global environment where national policy has such a dramatic effect on land use and land cover, the factors behind land-use change merit close examination.
Topic:
Agriculture, Economics, Migration, and Labor Issues
Political Geography:
China, Asia, Thailand, and Southeast Asia