Impact of rapid urbanization on communicable and
non-communicable diseases in China
Urbanization and Health in China, the University of Sydney
Dr. Yi Hu
A/Prof. Zhijie Zhang and Prof. Qingwu Jiang
Laboratory for Spatial Analysis and Modeling
Department of Epidemiology and Biostatistics
School of Public Health
Fudan University
Nov. 28, 2013
The starting points for this talk
• The urbanization is rapid in China.
• The health problems are challenging.
• What we are going to do?
1. Urbanization in China
Urbanization refers to the increasing
amount of people that live in urban
areas (Wikipedia).
Urbanization predominantly results
in the physical growth of urban
areas, be it horizontal or vertical.
The rate of urbanization increased rapidly
60
50
50
40
30
30
25
20
20.4
20.1
19
11
10
0
1950
1960
1970
1980
1990
2000
Urbanization in China increases linearly after 1985.
2010
• In 2004, 42% of
Chinese were
living in urban
areas;
•By 2040, more
than 1 billion will
be living in cities,
meaning another
400 million will be
urbanized in the
next 30 years.
The Chinese Government is pursuing a policy of urbanization, and
currently China has 28 city clusters with varying degree of size and
development, most still in an embryonic stage.
Three major city
clusters in the costal
zone:
• Beijing-Tianjin
• Yangtze River deltaShanghai
• Pearl River deltaGuangzhou
One major inland city
cluster-Chongqing
• Currently (up to 2012), about 52.6% of the population live
in 0.4% of the land area (urban buildup area), consume 60%
of the food, and create over 88% of GDP in China (National
Bureau of Statistics);
• Efficient in terms of food consumption and GDP;
Economic reform in the late 1970s
Within-country migration policies
Drivers of urbanization
Surplus agricultural laborers
Increasing urban-rural income
Conversion of farmland
(Yeh et al., 2011. UNFPA&IIED)
Impacts of urbanization
Urbanization
Environmental change
(physical and social)
Health
Environmental change
Urbanization: urbanized way of pollutant dischargehigh intensity per unit land and per capita, such as waste
discharge and concentrated vehicles;
Changes in landscape and land uses;
Air quality in China
Before 1970s, anthropogenic
aerosol pollutions were very low.
The aerosol levels started
increasing in the mid 1970s,
when economical development
rapidly increased.
Aerosol pollution reached a
maximum in the mid 1980s, and
has remained high up to the
present.
The long-term trend of aerosol extinction
coefficient (AEC) recorded in Guangzhou, China
from 1950s to 2000s (Tie et al., 2009).
Other aspect…
Emerging urban health trends
• Prosperity has resulted in general improvements in quality of life
and increased healthcare provision, but may also support unhealthy
life style;
• Decreasing communicable disease burden and mortality;
• Increasing non-communicable disease burden and mortality;
• The absolute difference of health risks between urban and rural
areas has increased over time.
(Zhu et al., 2011. ES&T)
The starting points for this talk
• The urbanization is rapid in China.
• The health problems are challenging.
• What we are going to do?
2. Communicable diseases
Zhang et al., 2012. Plos One
Zhang et al., 2012. Plos One
Reasons for decline
• Preferential policy from the central and local government
• Since the late 1990s, millions of dollars have been invested by
international donors to support China’s fight against infectious
diseases, including the World Bank; Britain’s Department for
International Development; the Australian government; The
Global Fund to Fight HIV/AIDS, TB and Malaria; and other
bilateral aid programs.
(Tang et al., 2013, Inf Dis Poverty)
AIDS
Annual transmission constitute of HIV and main modes of transmission of AIDS
IDU: injecting drug use; MTCT: mother-to-child transmission (Ministry of Health of China)
The distribution of cumulative AIDS cases until Sep. 2011
Ranking: Yunnan, Guangxi, Henan, Sichuan, Xinjiang (Ministry of Health of China)
• HIV likely entered China through rural border regions and
subsequently spread throughout the country via migrants.
• Once HIV spread from migrants (floating population) to
local permanent residents, subsequent transmissions
between permanent residents and within the general
population occurred rapidly and increasingly sexually. Rates
of HIV/AIDS among permanent urban residents,
particularly women and elderly men, have increased
significantly in recent years
influenza
Appearance of human influenza virus
H9
H5
H7
H5
H9
H5
H1
H3
H1
H2
Hong Kong flu
1918
1957
1968
Spanish flu
Asian Flu
1977
Avian Flu
1997
1998/9
2003
2004---
Mutation and potential crossspecies transmission of avian
influenza virus
Direct costs: a large number of human
cases and hospitalizations and death of
economic animal;
Indirect costs: the socio-economic impact.
Effects of urbanization
• The three key parameters in influenza emergence are
human and animal population density, intense contact
between different species to facilitate cross-species
transmission, and a prevalence of respiratory diseases
• Livestock population , raised for meat supply, also
plays a role in increasing the pathogenic strains of
influenza.
(Huo et al., 2006. Virginia Review of Asian Studies)
Schistosomiasis
Map of the epidemic status of schistosomiasis japonica before the
1950s in China
Map of the epidemic status of schistosomiasis japonica in China, 2000
Transmission interrupted
Disease still endemic
Transmission controlled
Annual number trend of cases infected with S. japonicum in China from 1999
to 2010
Cases including acute and chronic cases
(Department of Disease Control, Ministry of Health)
Map of the epidemic status of schistosomiasis japonica in China, 2010.
Transmission interrupted
Disease still endemic
Transmission controlled
In China…
China is experiencing a shift in disease profile, towards noncommunicable chronic diseases, and urbanization may well play a
big role, possibly through changes in life styles and environmental
pollution, endocrine disrupting compounds, particulate matters etc.
3. Non-communicable diseases (NCDs)
• China has experienced a dramatic increase in mortality and
morbidity caused by NCDs.
• In 2005, deaths from NCDs accounted for 80% of all deaths
(total 10.3 million) and 70% of total disability adjusted lifeyears lost (total 195.7 million).
• It is likely that the prevalence of NCDs will continue to rise
given the advancing population aging, and increased exposure to
health risk factors due to environment and lifestyle changes
associated with rapid urbanization.
Increasing trend of mortality of 6 major chronic diseases in China
CHD: Coronary Heart Disease
Cancer
Rural versus urban differences in mortality rate (/100,000) in the top five most
common cancers in China over the last 40 years.
(Zhu et al., 2011, ES&T)
Several large-scale prevalence surveys of diabetes in China
Year of Survey/
Criteria of
diagnosis
Sample
size
Age
(Yrs)
1980*
Lanzhou meeting
300,000
Whole
population
0.67%
-
Urinary glucose
+Bread meal
PBG2hΔ
1986
WHO 1985
100,000
25—64
1.04%
-
Bread meal
PBG2hΔ
1994
WHO 1985
210,000
25—64
2.28%
2.12%
Bread meal PBG2h
1996
WHO 1985
43,000
20—74
3.21%
4.76%
---
2002
WHO 1999
100,000
≥18
Urban 4.5%
Rural 1.8%
-
≥20
9.7%
Urban 11.4%
Rural 8.2%
15.5%
FPG, OGTT
≥18
11.6%
Urban 14.3%
Rural 10.3%
50.1%
FPG, OGTT, HbA1c
2007-08
WHO 1999
2010
ADA 2010
46,000
98,658
Prevalence
of DM
Prevalenc
e of IGT
Screening
methods
FBG
* Criteria of diagnosis ：FPG≥130mg/dl and/or postprandial 2h ≥200mg/dl and/or OGTT> (0 min 125, 30 min 190,
60 min 180, 120 min 140 or 180 min 125；O-toluidine method, 100g glucose）;
Δ PBG2h=postprandial plasma glucose 2h；FBG=fasting blood glucose
Prevalence of Diabetes and Pre-diabetes and Absolute Numbers
of Cases among Chinese Adults 20 Years of Age or Older (2008)
Total diabetes includes both previously diagnosed and previously undiagnosed
diabetes. Prediabetes was defined as impaired fasting glucose or impaired glucose
tolerance. (Yang et al., 2010. N Engl J Med )
Prevalence of Diabetes and Pre-diabetes among Chinese Adults 18 Years
of Age or Older (2010)
Prevalence of diabetes
Prevalence of pre-diabetes
(Xu et al., 2013. JAMA)
The starting points for this talk
• The urbanization is rapid in China.
• The health problems are challenging.
• What we are going to do?
4. Research and policy needs
• Most low- and middle-income countries are now facing a dual
burden of epidemics of NCDs and communicable diseases.
• These diseases share some common features, such as an
overlapping high-risk population, long-term care needs, supportive
interventions, and co-morbidities (e.g. diabetics among TB
patients).
• Multi-sectoral cooperation and coordination will be critical to
tackle these emerging public health challenges through the
implementation of responsive, pro-poor policies and innovative
strategies.
Reform initiatives in China:
• the establishment and expansion of health insurance schemes for
rural residents, which is the New Cooperative Medical Scheme
(NCMS); the unemployed or informally employed urban residents,
which is the Urban Resident Basic Health Insurance (URBHI); and
the Urban Employee Basic Health Insurance (UEBHI).
Limitation: the service benefit packages offered by NCMS and
URBHI are still very limited and focus on paying for inpatient care.
Substantial costs incurred from frequent visits for treatment of
chronic diseases have become a major factor in medical
impoverishment in China.
Policy needs
• Untangling the causal web linking urbanization and health needs
a multidisciplinary approach;
• Policies to mitigate the adverse health effects of urbanization
need to meet the health-care needs of highly vulnerable
populations, and must follow up these populations as they
potentially transfer health-care burdens to rural areas;
• The next decade of urbanization in China will demand
innovative health policies that address the needs of new urban
residents while providing health services for people (especially
older people and the very young) who remain in rural areas.
China has the capacity to deal with problems
• Learning from China’s own experience of rapid development
• Universities have a major role to play
• New ways of doing things
Acknowledgment
We would like to thank Dr. Chenglong Xiong, Dr.
Tiejun Zhang, Dr. Yihan Lu, Dr. Wanghong Xu,
and Dr. Zhijie Zhang for providing the disease
data, China Studies Center for the invitation,
and Dr. Mu Li for the arrangement of this trip.
Thanks, and welcome
collaborations in our
lab!