Faculty of Medicine Introduction to Community Medicine Course

(31505201)

Unit 3 Public Health/Environmental Health

Functions and Achievements of public Health By

Hatim Jaber MD MPH JBCM PhD

9-10-2016

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Presentation outline

Time

Introduction to Unit 3 Public Health 12:00 to 12:10

Public Health definition, dimension and components.

12:10 to 12:20

Achievements of Public Health Public Health Approach

12:20 to 12:30

Environmental Health : Concepts and Definitions

12:30 to 12:50

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Introduction to Unit 3 Public Health and Environment

5 lectures

• Introduction to Public Health and Environment-- 9-10-2016

• Environment 1- Air pollution—11-10-2016

• Environment 2- Water Quality and Food Safety - 13-10-2016 ??????????????

• Environment 3 -Waste Management --16-10-2016

• Occupational Health 4 – 18-10-2016

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Public health • The WHO has defined it as “The science and art of preventing

disease, prolonging life, and promoting health through organized community efforts”

• Public health is a combination of scientific disciplines (e.g.,

epidemiology, biostatistics, laboratory science, social science, demography) and skills and strategies (e.g., epidemiological investigations, planning and management, intervention, evaluation) that are directed to the maintenance and improvement of the health of people.

• Public health is both a body of knowledge and also means to

apply that knowledge

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Public health is thus a social institution, a discipline, and a practice

and…

…a dynamic state of complete physical, mental, spiritual, and social well-being and not merely the absence of disease or infirmity.*

Public health is “What we

as a society do collectively to assure the conditions in which people can be healthy.”**

Health is…

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What does What does medicine do? public health do?

Saves lives one at a time Saves lives millions at a time

Both of these disciplines are based on science, however, please note:

Public health touches EVERY individual, EVERY day. Addressing the cause of death and emergencies cannot be done one person at a time. Population-based public health means strategy is needed. It is important to understand the difference between medicine and public health

because while medicine saves one life at a time, public health saves millions of lives at a time.

What is Public Health?

• The sum of all official or governmental efforts to promote, protect, and preserve the people’s

health.

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Who is Responsible for the Public’s Health?

• Government agencies

– federal,

– state and

– local

• Non-governmental agencies, such as non-profit organizations.

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Three Core Functions of Public Health

Assessment

◦ What are the health problems of a population or individual?

Policy Development

◦ Collectively deciding which actions or interventions are most appropriate for the problems identified.

Assurance

◦ The necessary interventions will be put into place, assuring conditions in which people can be healthy.

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http://www.health.gov/phfunctions/public.htm 12

Public Health Accomplishments- Achievements

1. Vaccination 2. Motor-vehicle safety 3. Safer workplaces 4. Control of infectious diseases 5. Decline in deaths from coronary heart disease and stroke 6. Safer and healthier foods 7. Healthier mothers and babies 8. Family planning

9. Fluoridation of drinking water 10. Recognition of tobacco use as a health

hazard

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Public Health Approach

• Define the health problem. • Identify risk factors associated with the

problem. • Develop and test community-level

interventions to control or prevent the cause or the problem.

• Implement interventions to improve the health of the population.

• Monitor those interventions to assess their effectiveness

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Public Health

Approach

Problem Response

Surveillance: What is the

problem?

Risk Factor Identification: What is the

cause?

Intervention Evaluation:

What works?

Implementation: How do you

do it?

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A Sampling of Public Health Professions

• Alcohol, tobacco and other drugs • Chiropractic health care • Community health planning and

policy development • Environment • Epidemiology • Food and nutrition • Gerontological health • Health administration • HIV AIDS • Injury Control and Emergency

Health Services • International Health • Maternal and Child Health

• Medical Care

• Mental Health

• Occupational Health and Safety

• Oral Health

• Podiatric Health

• Population, Family Planning & Reproductive Health

• Public Health Education and Health Promotion

• Public Health Nursing

• School Health Education and Services

• Social Work

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Environmental Health: Concepts and Definitions

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What is environment?

Environment is defined as

“the surroundings in which an organization operates including air, water, land and natural resources, flora, fauna, humans and their inter relations” – ISO Definition

. Webster's Dictionary defines the environment as,

"The circumstances, objects, conditions by which one is surrounded, the complex of physical, chemical and biotic factors, that act upon an organism, or an ecological community and determine its form and survival, the aggregate of social, cultural factors that influence the life of an individual or community."

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ENVIRONMENT All that which is external to man is the environment

broadly speaking.

The concept of environment is complex.

The external environment or the Macro-environment is

said to be responsible for millions of preventable

diseases originating in it.

Micro-environment is the Domestic environment in which

man lives.

The term Internal environment is some time used for the

environment inside the body EXTERNAL ENVIRONMENT:

“All that is external to the individual human host, living and non-living, and with which he is in

constant interaction”.

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ENVIRONMENTAL IMPACT

Environment (Physical, biological and psychosocial)

Human activities health of individual

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EPIDEMIOLOGICAL TRIAD

ENVIRONMENT

VECTOR

AGENT HOST

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Health and Environment Perspective of Relations

Personal Health

Family Health

Occupational Health

Public Health

Environmental health

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Environmental Health?

The study of how the environment affects your health.

Food

Air

Water

Sunlight

Noise

Soil

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Health and environmental relationship

1- Environmental conditions help to determine peoples health and how long they will live. - They can affect reproductive health and choices related to number of children.

2- They can help determine prospect of social cohesion and economic growth, with further effects on health.

3-Changes in the environment i.e. Pollution and degradation, climate change, extremes of weather also change the prospects for health and development.

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Health and environmental relationship

4- Environmental condition contribute significantly to

communicable diseases, which account for about 20 – 25 % of deaths annually world wide. 5- Unclean water and associated poor sanitation kill over 12 million people each year. 6- Air pollution kills nearly 3 million or more. 7- Change in land use can create new breeding grounds of vectors, Schistosomiasis in Sudan and Egypt

Health and environmental relationship 8- The cleaning of the tropical forest creates hardpan on which rainwater can collect and mosquito can breed. Malaria results over 1 million death each year and accounts 300 million new clinical cases each year. Malaria causes 10 % of the death in sub – Sahara Africa. 9- It has been estimated that roughly - 60% of the global burden of disease from acute respiratory infections. - 90% from diarrhoeal disease, - 50% from chronic respiratory condition and - 90% from malaria could be avoided by simple environmental intervention.

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Hazards

A hazard is anything in the environment that can hurt you or make you sick.

Bacteria & viruses

Harmful chemicals

Loud noises

Tobacco smoke

Stress

I- Biological hazards These are living organisms or their products that are

harmful to humans

A. Water-borne diseases are diseases that are transmitted in drinking water

1. Examples are polio virus, hepatitis A virus, Salmonella, Shigella, cholera,

amoebic dysentery, Giardia, and Cryptosporidium.

2. These disease organisms are shed into the water in feces, and can produce

illness in those who consume untreated, contaminated water.

3. Our municipal water treatment facilities are usually able to purify water by

removing these agents or killing them by disinfecting the water.

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B. Food-borne diseases

are diseases transmitted in or on food

1. Examples of food-borne agents are the bacteria Salmonella,

serotype enteritidis, Escherichia coli, as well as other agents.

2. To protect against food-borne diseases, sanitarians from

local health departments routinely inspect food service

establishments (restaurants) and retail food outlets

(supermarkets) to verify that food is being stored and handled

properly.

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C. Vector-borne diseases

are those transmitted by insects or other arthropods

1. Examples are St. Louis encephalitis and La Crosse

encephalitis transmitted by mosquitoes and plague and

murine typhus transmitted by fleas.

2. Improper environmental management can cause vector-

borne disease outbreaks.

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II. Chemical hazards

result from mismanagement or misuse of chemicals resulting in an

unacceptable risk to human health

A. Pesticides are chemicals

that have been manufactured for the purpose of reducing populations

of undesirable organisms (pests)

1. Examples of categories of pesticides are herbicides and insecticides.

2. Most pesticides kill non-target organisms as well as the target, or pest

species.

3. The wise use of pesticides can protect human health and agricultural

crops.

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II. Chemical hazards

B. Environmental tobacco smoke (ETS)

is an environmental hazard produced by millions that smoke

1. Diseases associated with ETS include lung cancer and perhaps heart disease.

2. ETS contains 4, 000 substances.

3. The EPA has classified ETS as a Class A carcinogen.

4. Smoking has been increasingly restricted from public buildings and from many

private work sites.

5. Regulation of smoking seems to be the best approach to controlling this

pollutant

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II. Chemical hazards

C. Lead

is a naturally occurring element that is used in the manufacturing of many industrial and domestic products

1. Health problems associated with the over exposure to lead are anemia, birth defects, bone damage, neurological damage, kidney damage, and others. 2. Exposure is by ingestion and inhalation. 3. Children are particularly at risk from eating peeling lead paint. 4. The prevalence of very high blood lead levels among young children declined significantly between 1984 and 1994 primarily because the removal of lead from gasoline. 5. Occupational exposure is a major source of lead intake for adults.

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III. Physical hazards

include airborne particles, humidity, equipment design and radiation A. Radon contamination results from over exposure to radon gas. 1. Radon gas arises naturally from the earth and sometimes occurs at dangerous levels in buildings and homes. 2. Breathing in radon gas can cause lung cancer. 3. Homes can be tested for the presence of radon gas for $20.

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IV. Psychological hazards are environmental factors that produce psychological

changes expressed as stress, depression, hysteria.

V. Sociological hazards are those that result from living in a society where one

experiences noise, lack of privacy and overcrowding.

Population growth may be a sociological hazard.

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Site and Location Hazards Natural disasters are geographical and

meteorological events of such magnitude and

proximity to communities that they produce

significant damage and injuries.

1. Examples are cyclones, earthquakes, floods,

hurricanes, tornadoes, typhoons, and volcanic

eruptions.

2. The magnitude of devastation of these events can

sometimes be great.

3. Biological, psychological and sociological hazards

may increase following a natural disaster.

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Route #1: Inhalation

Inhalation:

Breathing. When chemicals enter the body through this route of exposure, they can get stuck in the lungs and/or be taken up into the bloodstream.

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Route #2: Ingestion

Ingestion:

Swallowing (usually by eating or drinking). When chemicals enter the body through this route of exposure, they can easily be taken up into the bloodstream.

Route #3: Dermal Absorption

Dermal Absorption:

Absorbing a chemical through any part of the skin, including the eyes. When chemicals come in contact with the skin, they can sometimes enter the bloodstream through this route of exposure.

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Natural Environment • Hydrosphere

The hydrosphere represents one component of earth's system, operating in conjunction with the solid crust (lithosphere) and the air that envelopes the planet (atmosphere). According to the research, hydrosphere basically a combined mass of water that is found on earth, that makes up around 71% of the earth surface which is covered with water. Atmosphere Its major components are Nitrogen (78%), Oxygen ( 20.96% ), Argon ( 0.93% ), Carbon-dioxide ( 0.032% ), and other inert gases. The atmosphere filters the incoming ultra-violet (UV) radiation and protects the earth’s surface. Troposphere, Stratosphere, Mesosphere, Thermosphere are the four types of atmosphere. 41

The four types of

Atmosphere • Troposphere: 8-18 km, close to

earth surface

• Stratosphere: up to 50km,

OZONE- absorbs harmful ultraviolet radiation from sun

• Mesosphere: > 50 km

• Thermosphere and Exosphere= upper atmosphere

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Natural Environment

• Lithosphere The earth's crust consists of rocks and soils made up of different chemical elements and minerals. The lithosphere occupies 30% of the total Earth’s surface. The lithosphere is about 100 km thick, although its thickness is age dependent (older lithosphere is thicker). Anthrosphere The anthroposphere (sometimes also referred as technosphere) is that part of the environment that is made or modified by humans for use in human activities and human habitats. It is one of the Earth's spheres. As human technology becomes more evolved, so do the impacts of human activities on the environment. Examples: deforestation for housing, land setup, etc.

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• 1. Natural environment:

4 spheres

• 1.1 Biosphere = Space occupied by life

• 1.2 Atmosphere = Space occupied by air

• 1.3 Lithosphere = Space occupied by solid

• 1.4 Hydrosphere = Space occupied by

water

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Atmosphere

Hydrosphere Lithosphere

Ecosphere

Biosphere

2 Man Made Environment (Socio-cultural)

• Cultural OR man made environment : It includes 1)Industries, 2)Transport and communication, 3)Population, 4)Traditions, 5)Political situations etc…

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Interaction between each biotic

level with physical environment

through energy, matter, and

information produces

characteristic functional system.

"Biosystem" or "life"

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What Is An Ecosystem

An ecosystem is a natural unit consisting of all plants, animals and micro-organisms (biotic factors) in an area functioning together with all of the non-living physical (abiotic) factors of the environment.

Ecology is the study of ecosystems.

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Environmental Sanitation: WHO defines environmental sanitation as “the control of all those factors in man’s physical environment which exercise or may exercise a deleterious effect on his physical development, health and survival”. = eliminating or modifying the harmful factors and

promoting the beneficial ones towards promotion of human health

COMPONENTS OF ENVIRONMENT:

PHYSICAL: air, water, soil, housing, climate, geography,

heat, light, noise, debris, radiation, etc.

BIOLOGICAL: man, viruses, microbial agents, insects,

rodents, animals and plants, etc.

PSYCHOSOCIAL: cultural values, customs, beliefs, habits,

attitudes, morals, religion, education, lifestyles, community

life, health services, social and political organization.

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What is environmental justice?

Environmental Justice (EJ) means that everyone has a right to live in an environment that doesn’t make them sick, regardless of their race, culture, or income.

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