Liberal Studies Public Health Notes 1wx59

M5 PUBLIC HEALTH THEME ONE Understanding of Public Health

SECTION 1 Health and Public Health

Do you think she is healthy? • Her name is Tsang Tsz

Kwan • She is blind and deaf • She ‘reads’ book by lips • http:// hk.apple.nextmedia.c om/news/art/20130716 /18336206

1.1 Definition of ‘HEALTH’ WHO (World Health Organization) defines

Body (physical health)

Spirit (mental health)

Society (social wellbeing)

HEALTH

1.1 Definition of ‘HEALTH’ • Body • Refers to physical health • Proper functioning of all systems and organs in the body • Spirit • Refers to mental health • Including emotion, senses, memory • Society • Refers to social well-being • Positive interpersonal relationship and community life

1.1 Definition of ‘HEALTH’ • Health is not merely the absence of disease or infirmity. • There is a close relationship between physical and

mental health, as well as social well-being. For example, emotional stress may lead to heart diseases. • The definition of health is somewhat subjective. Many people determine their own health status based on how they define their lives and what things are important to them. • Class Work 1

1.2 Factors affecting health

1.2 Factors affecting and maintaining health 1. Physical environment 2. Social and economic conditions 3. Personal factors

by World Health Organization

1.21 Physical environment • Hygienic conditions e.g. clean water and air • Healthy and safe workplaces and homes • Well-planned communities and infrastructures • More health problems in developing regions

1.22 Social and Economic factors • Income and socio economic status • higher income and social status  better health. • The greater the gap between the richest and poorest people (c.f. gini coefficient, the greater the differences in health) • Education • low education level  more stress and lower self-confidence  poor health

• Employment and working conditions • people in employment are healthier • miners and construction workers often have lung problems • Social networks •

greater from families, friends and communities  better health.

1.23 Personal factors • Personal lifestyle • Diet? Fast food culture  meat > vegetable • Regular rest and exercise ? • Smoking ? Drinking ? • Personal character • Personal experiences • How we deal with stresses and challenges • Optimistic or pessimistic ?

• Others • Age – infants and the old have weaker immune system • Hereditary diseases (e.g. Thalassemia 地中海貧血 ) • Race – e.g. White people are more likely to have skin cancer

1.24 Remark • The context of people’s lives determine

their health, and so blaming individuals for having poor health or crediting them for good health is inappropriate. • Therefore, maintaining health is not just a personal matter.

What is public health?

• Public health involves topics related to the health of

individual, community, and world health • Using social resources to make sure people stay healthy • Focus on prevention of diseases • Include social measures and scientific knowledge

• Public health involves topics related to health of individual,

• • • •

community, and world health. It aims to facilitate the organized efforts of different sectors to create a hygiene environment through the allocation of social resources Using social resources to make sure people can stay healthy through adopting a healthy lifestyle. Focus on the prevention of diseases and formulation of relevant measures. Concern about the health of community, country, and world population Include social measures and scientific knowledge, which is interdisciplinary.

Public Health

Past

Promote health

Present

Prevention of disease

Food nutrition

Improve living environment

Access to community health care service

Vaccination subsidy

Improve medicare system

1.31 Definition of Public Health • Refers to the collective effort of the society and the use

of public resources to promote and maintain public health • It is the concern of the whole community • It requires coordination of different sectors of the community • It focuses on preventing and controlling diseases

• Issues concerning public health can generally be divided

into 3 domains: • Health protection • Health improvement • Health services

The 3 domains of public health issues Public Health Issues

Health Protection - Control of infectious diseases - Food safety - Environmental health

Health Improvement - Vaccination - Health education - Organ donation

Health Services - Public medical service - Reform of the medical system

** Two types of disease: infectious and non-infectious disease

1.32 Current public health challenges to HK • Challenges to health protection • Avian flu (H5N1) • Swine flu (H1N1) • Air Pollution • Food safety • Challenges to health improvement • Obesity, smoking, drug abuse and stress-related problems • Ageing population

• Challenges to health services • Primary care 基層醫療 – over-burden of public medical services • Health care reform – absence of medical insurance scheme • Managing chronic diseases 慢性病 due to ageing population

1.33 Evaluation of public health • Indicators used in HK to evaluate public health • Statistics on infectious diseases • Cases of infectious diseases and food poison etc. • Statistics on behavioural risks factors • Data regarding weight control, eating habits, physical activities etc. • Vital statistics • Death rate, average life expectancy etc.

Characteristics of public health • A focus on the whole community • An emphasis on prevention • An emphasis on collective responsibility for health (i.e.

every member of the society including individuals, public and private organisations, government, etc) • A concern for the socio economic factors of health and disease • A close partnership between health care providers, the government and the population served

Responsibilities of different stakeholders in maintaining public health • WHO  It is responsible for coordinating issues related to global public health. E.g. strengthening health and nutrition surveillance systems to enable monitoring of any changes, early warning of deterioration, and immediate life saving action through outbreak response and technically sound nutrition interventions • Government (local level) The Department of Health in HK executes the government’s healthcare policies. It protects people’s health through promoting health, preventing diseases, providing medical care and rehabilitation services, etc  Food and Health Bureau, Food and Environmental Hygiene Department, Centre for Health Protection and Hospital Authority

• NGOs (local/global level)  Promote healthy lifestyle, monitor the government and pressurize the government for improving public health conditions, cooperate with the government to maintain public health

Population structure of HK • Class work 2

1.34 Case Study: poverty and public health • http://www.youtube.com/watch?v=vVEc7MfUMvU

Class work 3 In sub-Saharan Africa, 71.8% of urban residents live in slums, where sanitation, clean drinking water and electricity are lacking. Pathogens that cause infectious diseases, such as cholera, dengue fever, and yellow fever, breed in ditches and dirty water. The crowded environment also enables the spread of pertussis ( 百日咳 ) and influenza. However, vaccination is not common. In Niger, immunization coverage in slums is only 35%. • Climate change is expected to bring more frequent and longer droughts to Africa. Droughts result in water scarcity, poor agricultural productivity and food shortage. Malnutrition in slums will get worse. Also, urban pollution leads to 49,000 premature deaths a year in Africa. Slums are often located near factories and roads. Many people living there have respiratory diseases. •

SECTION TWO Factors affecting the public understanding about public health

2.1. Factors affecting people’s understanding and decisions on health and public health issues Personal

Technology

Religion and culture

Economic

Public understanding about Public Health

Mass Media

Family

Education

Gender

Factors affecting people’s understanding and decisions on health and public health issues • Personal factors • Cultural and religious beliefs  e.g. some radical Judaists are against blood transfusion) • education  more access/awareness to health information) • economic situation  more income  afford the cost of better medicine, e.g. targeted

medicine @$15000) • gender and age  female is more likely to look for treatment when compared with male

Friends social networking groups

Family Determine a person’s opinion on public health

• The media • Delivery of health and public health information • Monitor of health and public health issues (e.g. 地溝油 ) - Arouse decision makers’ awareness of the incident - NGOs may pay attention to those loopholes upon reading the relevant news reports.

• Scientific evidence • Clinical research and statistical surveys • e.g. hazard of smoking • Government - medical system and policy • Quality of medical services • Health policies • Health education – can raise public’s awareness of precaution (e.g. cervical cancer screening) http://www.youtube.com/watch?v=ixSkIuOivjA

2.2. Stakeholders responsible for maintaining public health • Global level - World Health Organization (WHO) • WHO is responsible for coordinating issues related to

global public health, e.g. ensuring international cooperation and notification system when health crises arise • Strengthening health and nutrition surveillance systems to enable monitoring of any changes • early warning of deterioration, and immediate life-saving action through outbreak response and technically sound nutrition interventions.

2.2. Stakeholders responsible for maintaining public health • Local level – government • The Department of Health in Hong Kong executes the government’s healthcare policies. It protects people’s health through promoting health, preventing diseases, providing medical care and rehabilitation services, etc. • Non-governmental organization (NGOs) • Promote healthy lifestyle, monitor the government and pressurize the government for improving public health conditions, cooperate with the government to maintain public health etc.

SECTION TWO Development of Scientific theories and Public Health: Understanding of Infectious Diseases

2.1 The Development of Scientific Theory and people’s Understanding of Infectious Disease Period

Development of science and Explanation of diseases

Prehistoric times

Supernatural forces/ religious explanation

Fifteenth century

Theory of contagion ( 傳染性 )

Late eighteenth century

Quarantine ( 隔離 ) and isolation Sanitation Vaccination e.g. smallpox

Late nineteenth century

Germ theory

Modern

Epidemiologic Triangle ( 流行病學三角 )

Plagues in Roman Empire

Evolution of scientific knowledge in the age of the Renaissance

Late 18th CenturyQuarantine and isolation • Quarantine (in Italian means “forty days) is used to

separate and restrict the movement of well persons who may have been exposed to a communicable disease to see if they become ill. • Isolation is used to separate ill persons who have a

communicable disease from those who are healthy.

Late 18th CenturyVaccination • Vaccines are made from the same germs that cause

disease. But the germs in vaccines are either killed or weakened so they won’t make you sick. • The immune system reacts to the vaccine by making

antibodies. • The antibodies destroy the vaccine germs just as they

would the disease germs. Then they stay in your body, giving you immunity.

Modern: Epidemiology 流行病學 • A theory proposes that microorganisms are the cause of

many diseases • E.g. Cholera ( 霍亂 )

Modern: Epidemiology 流行病學 A specialized field of medical study that studies disease trends To examine the features of diseases through the analysis of disease distribution, trends and the environment

2.2. Impact of modern scientific development on public hygiene

(a) Inventions of instruments for diagnosis and treatment (•)Instruments for diagnosis: X-rays and CAT scanner (•)Medicines/technology for treatment: antibiotics and organ

transplant surgery  shortened the time for the course of treatment and patients’ recovery

b) Negative impacts of science and technology • Invention and adoption of advanced technology would

have negative impact on health • E.g. walk less because people use automobile • Although science and technology can help people

understand better about health, this does not necessary mean that the people would change their behaviour (e.g. smoking)

c) Questions and crisis accompanying modern scientific development • Population explosion in developing countries  Medical technology improve diagnosis and effectiveness of treatment  longer human life expectancy, the lower natural death rate  Low mortality rate  Population explosion exerts burden on the economy, environment, and resources of developing countries  E.g. World population hit 7 billion

d) What is the relationship between population explosion and public health • Problem of unclean drinking water and shortage of

freshwater o 20th century – water consumption of developed and developing

countries has increased by 18% and 50% respectively

• Aggravation of inequality  Advanced technology is costly The rich are more advantageous following the emergence of new technology Widening wealth gap aggravates the problem of inequality (e.g. Mental illness – public hospital $0.5/pill Vs. private doctor $50/pill)

• Moral issues Illegal smuggling of organs Development of embryonic stem cells Tailor made babies?

2.2 Epidemiologic Triangle ( 流行病學三角 )

Agent • Something that can cause disease

Bacterium

Host • Host is where the agent lives

Mode of transmission

2.2 Epidemiologic Triangle ( 流行病學三角 ) Definition

Examples

Agent micro-organisms that cause disease

‧ Micro-organisms: bacteria or virus ‧ Non micro- organisms: poisons or stress

Host stands for organism (humans or animals) that carries the disease

‧ The same micro-organism can have different effects on different hosts. It all depends on a wide range of factors such as: ‧ age, sex, ethnicity, immunity and human behaviors, personal lifestyle ‧ Physical environment such as climate, water and geography ‧ Biological environment such as population density, health care system, etc. ‧ Socio-economic environment such as wealth, religion and culture

Environment stands for external factors that affect the rate and mode of disease transmission

Vector of disease stands for the transmitter of disease.

‧ Biological: Mosquitoes which spread malaria; dogs spreading rabies ‧ Non-biological: contaminated needles transmit HIV

Prevention of infectious disease

Factors to consider in prevention of infectious disease

• Overall description of the epidemiologic triangle: A disease exists when a vector connects all three components If any of one of the connection between the environment, the host

and the agent is disrupted, the disease will stop existing. Therefore, the epidemiologic triangle is important to the prevention

and control of infectious diseases.

Example: Malaria

Example 2: Ebola

https://www.youtube.com/watch?v=bXWWPPm9W-M

Can you draw a epidemiologic triangle for Ebloa?

Bats family Wild animals eaten by people; close

Ebola virus

Hot and wet

2.3 Differences between epidemics and pandemics Scale

Epidemics ( 地區流行 )

Pandemics ( 世界大流行 )

An epidemic is specific to one city, region or country

A pandemic goes much further than national borders, covers a much wider geographical area, often worldwide.

It occurs when the number of people who become infected rises well beyond what is expected within a country or part of a country

When an infection takes place in several countries at the same time it then starts turning into a pandemic. It infects many more people than an epidemic.

Cause

Epidemics like influenza are generally caused by subtypes of a virus that is already circulating among people.

A pandemic is usually caused by a new virus strain or subtype - a virus human either have no immunity against, or very little immunity so the virus is much more likely to spread around the world if it becomes easily human transmissible.

Impact

Localized and cause fewer deaths.

Globalized and caused more deaths and greater socio-economic loss.

Videos

SECTION 3 SARS as a public health risk (infectious disease)

3.1. Definition of infectious disease • An infectious disease can be spread between human and

human, animal and animal, human and animal • Influenza covers the three transimission routes mentioned, including human flue transmitted among humans, swine flu transmitted among pigs and human swine influenza transmitted between human and pig. • Infectious diseases can be transmitted through the following routes: Droplet transmission (e.g. influenza) Over-the-air transmission (e.g. tuberculosis) Blood (e.g. AIDS) Fascal-oral transmission (e.g. cholera) Vector borne transmission (e.g. Dengue fever)

3.2. Outbreak of epidemic diseases • (a) Black Death of C14th • Most serious causing 75 million deaths worldwide • Unclear of the cause, people could neither take appropriate control measures nor understand the importance of hygiene. • Black Death in HK (the plague) 1894 • Lessons learnt regarding public health • Cleared the infected area (Tai Ping Shan area) • Improved drainage • Killed mice • Enacted public health and housing ordinances • Set up public bath houses • Set up the HK Pathological Institute • Aroused greatly people’s awareness of hygiene

(b) AIDS as a public health risk • The outbreak • First reported case in the US in 1981 • 34 millions infected and 1.7 millions died • Most new cases (2010) were reported in developing since people and even the governments misunderstand AIDS so they fail to prevent or control the spread of it.

AIDS • Lessons learnt regarding public health • Focus on ‘Prevention’, ‘Education’ and ‘Acceptance’ • Governments’ and NGOs’ active propaganda • Safety sex - use of condoms • Drug addicts don’t share syringes • Proper and guidance to HIV carriers

www.avert.org

(c) Avian Flu (H5N1) as a public health risk • The outbreak • https://www.youtube.com/watch?v=VBvGsEsLUaU 0 -1’54” • Cases recorded in HK in 1997, 2003 and 2010 and spread worldwide since 2003 • Lesson learnt– preventive and monitoring measures • Killed all chickens (vector of disease) • Regulating the sale of live poultry • Conducting regular cleaning of wet markets • Suggesting central slaughtering but was opposed by the industry

Avian Flu (H5N1) as a public health risk

What’s your view? Should chickens be blamed?

(d) Swine Flu (H1N1) as a public health risk • The outbreak 2009 • 猪流感之歌 https://www.youtube.com/watch?v=xVRgaXaz9g0

Swine Flu (H1N1) as a public health risk • lesson learnt • Quarantine the infected or suspected • Vaccination

Conclusion: The influences of outbreaks of epidemic diseases on the understanding of public health

• Outbreaks of epidemic diseases raised people’s alertness about hygiene. • In ancient times: People did not know about epidemic diseases, so it was

difficult for them to prevent diseases from spreading, which usually resulted in a large number of deaths.

• Present: Both the government and the public are aware that preventive

measures are effective in controlling and preventing infectious diseases. These measures include isolation, entry and exit control, tracking of the sources of diseases, disinfection and cleaning, as well as raising awareness of environmental hygiene. • Information is more developed than in the ancient times, and through

media’s reports, together with the government’s measures and appeals, the general public can grasp the latest health information in a short time, so they will be alert and take preventive measures. The deaths caused by diseases are also reduced.

International collaboration in preventing infectious diseases • As different countries and regions are becoming more and more

closely connected outbreaks of epidemic diseases are more difficult to control. Therefore, the development of international collaboration in public health has become an inevitable trend. • • Motivated by WHO, governments and non-governmental

organisations in the world have endeavoured to build a global public health system for the prevention and control of outbreaks of epidemic diseases. • • Worldwide preventive measures against infectious diseases will

undoubtedly arouse the awareness of the public. However, whether the various measures will be fully executed depends on the government’s responses and transparency, as well as the effectiveness of the allocation of resources.

Role of local government and public in preventing epidemic disease

• Outbreaks of epidemic diseases often pose great

challenges governments and their abilities to respond. • • Of course, a government is responsible for protecting

public health. However, only with the participation of the public and with everyone taking all health and preventive measures can the government’s measures become effective.

3.4. SARS 2003 • Background • In 2003, Hong Kong was attacked by an emerging infectious disease named Severe Acute Respiratory Syndrome (SARS). • The SARS epidemic which lasted from March to June 2003 was unprecedented in the modern history of Hong Kong in of its severity and magnitude. • During the epidemic, 1,755 HK people were infected and 299 of them died. • More than one-fifth of those infected were healthcare workers (HCWs) and eight succumbed to the disease. • It spread to 27 countries. 8096 infected and 774 died.

Problems of the government in handling SARS • Watch • https://www.youtube.com/watch?v=1Q2S5JSOk1A 香港心 - 全港抗炎 (SARS) 大行動主題曲 • https://www.youtube.com/watch?v=0zpW0bUH8-k 廣告時刻 | 2003 年 : 香港政府宣傳片 • https://www.youtube.com/watch?v=9p5CNDJCOIo 0 – 2’10’’ • 沙士烈士 • SARS Report 沙士報告 (watch video)

Problems of the government in handling SARS Problem 1 • Lack of collaboration between the HKSAR government and the mainland authority • e.g. The government was ive in acquiring information about the disease info from the mainland authority

Problem 2 • Lack of a sense of awareness/ prevention • e.g. health workers were unaware of the highly contagious nature of the disease and therefore got infected collectively

Problem 3 • Confused message delivered to the public • e.g. the government officials postponed the announcement of the outbreak of SARS and failed to raise the alertness among the public

Problem 4 • Lack of understanding about the diseases • e.g. SARS was a new disease and little information was available. Investigation and invention of medicines were therefore slow.

Impacts of SARS on public health in Hong Kong • Watch the video < 沙士十年 >

• Class work 4

What have Hong Kong citizens learnt from SARS? (1) Rising awareness of personal hygiene • People start to understand that personal hygiene is crucial in the

prevention of infectious diseases. (2) Transparency is of crucial importance • Governments worldwide understand that those cases identified must not be concealed from the public. If not, the consequence will be unbearable. • Delay in the dissemination of information on the epidemic may result Hong Kong’s and other cities’ not being able to combat the spread of the epidemic. • Having learnt from SARS, governments worldwide are more transparent and honest when disseminating information on the epidemic, such as reporting to the WHO more quickly.

(3) Inadequate measures and knowledge • In January 2003, experts from Guangdong published a report on SARS, claiming that the disease was highly infectious in hospitals. Therefore, infection control in hospitals is of immense importance. • When collective infection was found in Prince of Wales Hospital in Sha Tin in March 2003:  The infection control was inadequate to prevent the spread of

SARS within the hospital, and the disease cannot be stopped from spreading into the community.

Medical staff’s knowledge in infection control and the supply of

protective gear were found to be inadequate. Medical staff laced basic training in dealing with the mass outbreak of infectious diseases. It was not until the outbreak of SARS that the problem surfaced.  After SARS, Hong Kong received extra resources on the

prevention and control of infectious diseases, such as the establishment of the Centre of infectious diseases in Princess Margaret Hospital. Hong Kong has been in the forefront in of preventing and

controlling infectious diseases. It has received extra resources.

Steps in the management of an infectious disease outbreak

Preparation 準備

Detection 發現

Response 反應

Evaluation 評估

1. Preparation  Surveillance system: regular reports  Outbreak response plan for each disease:    

resources, skills and activities Stockpiles: sampling kits, appropriate antimicrobial, intravenous fluids, vaccines Contingency plans for isolation wards in hospitals e.g. St Margaret’s Hospital Laboratory Setting up of Centre for Health Protection

2. Detection

2. Detection • To ensure rapid detection of an outbreak in an

emergency situation, it will be necessary: • to set up an early warning system within the surveillance system, with immediate reporting of diseases with epidemic potential; • •to train clinical workers to recognize priority diseases/syndromes and report cases of priority diseases/syndromes

3. Response

4. evaluation

How does the outbreak of SARS reflect the role of globalization? • Can be discussed in the following aspects • Spread of the disease • Information flow • Control of the disease

Globalization and Spread of the disease • ORIGIN OF SARS: Guangdong province • Spread to Hong Kong by a Chinese visitor • Further spread to the rest of the world as visitors got

infected in a hotel in Hong Kong • Countries around the world are closely connected and interact with each other in the way that a local event may affect other places, or even the whole world within a short period of time.

2. Information flow Hong Kong

Different countries

reported the infected case to Hong Kong and alert the government to handle the crisis.

At first, China concealed the

China

news of SARS outbreak. However, the information about SARS outbreak in Beijing on the internet was soon widely spread . The WHO gave pressure to the Chinese government to make daily reports of the SARS cases

Globalization and Information flow • Under a globalization background, with the ever-

upgrading communication and information technology, people will be able to find ways to break up the blockage set up by any istrations or authorities. The whole world is watching!!

3. Control of disease Scientists in Hong Kong remotely connected 80 clinicians

from 13 countries to develop a uniform treatment plan and a new serum test for control of SARS. Global cooperation or global governance

between countries and authorities is inevitable when facing a global common crisis.

SECTION FOUR Development of Scientific theories and Public Health: Understanding of Non-infectious Diseases (1) –

Mental Disorder

3.2 Understanding of Mental Disorder • A test

assessment • 0-10 分：精神壓力程度低但可能顯示生活缺乏刺激，比較

簡單沉悶，個人做事的動力不高。 • 11-15 分：精神壓力程度中等，雖然某些時侯感到壓力較 大，仍可應付。 • 16 分或以上：精神壓力偏高，應反省一下壓力來源和尋求 解決辦法

Understanding mental disorder • Mental disorder refers to disorders in the functions of the

brain or nervous system, which lead to abnormalities in one’s perception, cognition, emotions and behavior. • Mental disorder can be further divided into neurosis and

psychosis.

Neurosis • Mental imbalance which causes distress • Symptoms:

anxiety, depression

Psychosis • Mental state that impairs thoughts, perception and judgment • Symptoms: Hallucinations, delusion

3.21 Causes of mental disorder Factor

Examples

Physiological factor

Brain problems

Psychological factor

Personal character and emotion

Environmental factor

Pressure, great changes, traumatic experience 創傷 and drug effects

Hereditary factor

Schizophrenia 精神分裂症 and manic depressive disorder 躁狂抑鬱症

3.22 Situation in HK • The number of mental patients has been rising

mental patients in thousand

• Supply of professional medical services cannot meet the demand • Families of the patients live under great pressure • Ex-mental patients have great difficulties to adapt to society e.g.

social discrimination

Class work 6 • http://www.youtube.com/watch?v=UdhGhs0xLm0 • 時事追擊 精神病患者 > • http://www.youtube.com/watch?v=G7WcX15Uh-

Q&playnext=1&list=PL89D055850B01CD6C&feature=res ults_video

Problems faced by mentally ill patients • Discrimination/ Social pressure

e.g. Hard to get jobs after recovery (Source C) • Discrimination in community

• Lack of resources

e.g. Long waiting time for mental diagnosis (Source C) e.g. Low doctor-patient ratio (Source B) e.g. Lack of rehabilitation facilities in urban communities (Source B & D)

Reasons behind the problem 1. Personal level • Lack of awareness and understanding (Source A) e.g. Ah Ching felt reluctant to disclose her problems to people around as she did not realize it would turn into depression later. She delayed a year to seek medical help.

2. Socio-cultural level • Chinese traditional thinking regards mental disorder as a moral problem (Source D) This prevents people from seeking medical help as they often feel shameful • Chinese tend to seek help from family and friends

This postpone the proper treatment of many mental patients

• Media exaggeration

Media often selectively report extreme cases of mental illness by exaggerating titles and pictures This creates a labeling effects on mental patients

3. Political level Lack of long-term policy (Source D) - Treatment of mental illness is often conducted separately from the mainstream community. Rehabilitation facilities are inadequate in urban areas. - Education concerning mental illness is fragmented and inadequate.

SECTION 5 Development of Scientific theories and Public Health: Understanding of Non-infectious Diseases (2) –

Chronic disease

Understanding of Chronic diseases

5.1. Understanding of Chronic diseases • Some facts about chronic diseases Chronic diseases are diseases of long duration and generally slow progression. They are also known as ‘life-style diseases’ or ‘diseases or civilization; Examples: heart diseases, stroke, cancer, chronic respiratory

diseases and diabetes. Chronic diseases by far the leading cause of mortality in the world,

representing 63% of all deaths. Out of the 36 million people who died from chronic disease in 2008, nine million were under 60 and 90% of these premature deaths occurred in low- and middle-come countries.

5.2. Causes of Chronic diseases

Non-modifiable risk factors Behavioural risk factors Cultural and environmental risk factors

• Age • Gender • Inheritance • Lack of exercises • High-calorie diet • Smoking and alcohol abuses

• Pollution • Cultural and religious malpractices

5.3. Chronic diseases as a potential threat to public health of HK

Increasing cases Ageing population Chronic diseases a potential threat Absence of Imbalance of mandatory medical healthcare services insurance scheme

5.4. Case study :Obesity • Obesity and overweight • Overweight and obesity are defined as abnormal or excessive fat accumulation that may impair health. • Body mass index (BMI) is a simple index of weight-for-height that is

commonly used to classify overweight and obesity in adults. It is defined as a person's weight in kilograms divided by the square of his height in meters (kg/m2).

• The WHO definition is: • a BMI greater than or equal to 25 is overweight • a BMI greater than or equal to 30 is obesity.

What is Globesity? • What is the public health problem reflected?

Wealth and Obesity

Wealth and Obesity • Class work 5b

Is legislation feasible in controlling Obesity? • http://www.youtube.com/watch?v=t09QRHez9L4

• Class work 5c • 紐約市長彭博 (Michael Bloomberg) 極力推動的禁止銷售大杯含糖飲

料政策， 30 日遭到紐約州最高法院上訴法庭駁回。不過彭博立刻宣 布打算上訴。 　　紐約市衛生局 (New York City's Board of Health)2012 年 9 月同 意，在紐約市各餐館以及包括體育場與音樂廳在內等場所，禁止銷 售 16 盎司 (470 毫升 ) 以上含糖飲料。 　　然而今年 3 月，就在距離這項政策生效前幾小時，下級法院認 為這項政策「武斷且恣意」，予以駁回。紐約市原本將開禁止銷售 大杯飲料的先例，受到全球矚目。

• 中央廣播電台 reports

Obesity problem among Hong Kong students

Fat tax in Denmark • http://www.youtube.com/watch?v=t09QRHez9L4 • A ‘fat tax’ was introduced in October 2011, in an attempt

to limit the population's intake of fatty foods. • Foods containing more than 2.3% saturated fat - including

dairy produce, meat and processed foods - were subject to the surcharge.

Should HK government implement the ‘fat tax’ similar to that adopted in Denmark ?