public health midterm lec 1, 2, 3 and 4

What is public health?

1. preventing disease

2. prolonging life

3. and promoting physical health and efficience

Public health goals are accomplished through

• Organized community efforts for the sanitation of the environment

• The control of community infections

• The education of the individual in principles of personal hygiene, etc.

• Organization of medical and nursing services 

• Development of the social machinery

Core Functions of Public Health 

Assessment - monitor health & diagnose problems

Policy development - uses scientific knowledge to develop a strategic approach to improving the community’s health. 

Assurance - ensuring that services needed for the protection of public health in the community are available to everyone 

Why is public health controversial?

• Governments and people can’t agree on responsibility, and people think their freedom might be affected

Controversial definition 

The missions of public health as defined by the institute of medicine report. - fulfilling society’s interest in assuring conditions in which people can be healthy

Economic impact

• Most public health measures have a negative economic impact of some kind on some segment of the population or on some industry.

Individual liberty

One of the primary purposes of government is to  “promote the general welfare” -  Health and safety, together with economic well-being, are the major factors that contribute to the general welfare. 

Tragedy of commons 

• Shared resource gets overused, everyone shares something but attempts to get the most for themselves 

• Garret Hardin in 1968,  If each herdsman tries to maximize his gain by keeping as many cattle as possible on the pasture—the commons—the pasture will be overgrazed.

Moral and religious opposition

• Public health often arouses controversy on moral grounds 

• Sexual and reproductive issues are often at issue

• The public health approach to these problems includes sex education in schools and the provision of contraceptive services, especially condoms.

History of public health in Canada

• Indigenous peoples have inhabited the North American continent for thousands of years and their health, social, economic and physical conditions were adversely affected by increased European immigration, which began in the 1600s.

Key historical figure & concepts

• Edward Jenner → Developed smallpox vaccine
  
  

• Miasma Theory → Disease caused by “bad air”
  
  

John Snow → Cholera, Broad Street Pump → father of epidemiology

Notable contributors to rise of sanitation & germ theory

• Louis Pasteur → Germ theory, vaccine for anthrax

• Robert Koch → Identified TB bacteria

World war l era

• Controversial sexual health education
  
  

• Spanish Flu (1918) → Major pandemic
  
  

• Led to creation of Federal Department of Health
  
  

Canadian Public Health Association founded: 1910

Post confederation 

• Local and provincial boards were still underway but the new federal government allowed for strengthening of economic infrastructure.

Advances in sciences leads to changes in public health thought

1. Bacteriology and germ theory strengthened arguments for sanitation measures

2. This new way of thinking was called the sanitary idea, and it first spread amongst medical elites

What is the Canada health act ?

• of 1984 augmented the 1867 constitution act - facilitate reasonable access to health services and applies to all services deemed medically necessary  

Public administration 

• operate on non profit basis 

Comprehensiveness

• insurance all medically necessary services provided by hospitals 

Universality

• all insured persons to health insurance coverage in uniform terms and conditions 

 

Accessibility

• access to medically necessary physician services with no financial barrier 

Portability

• visiting another province or territory 

What is Epidemiology? 

• The study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to prevent and control of health problems. – John Last

• Uses of epidemiology 

1. Etiology 

• Studying the cause(s) of disease(s) or conditions

• Determining primary risk factor or agent, or ascertaining causative factors

• Analyzing contributing factors

2. Studying Disease Spread

• Analyzing the characteristics of the agent or causative factors

• Determine mode of disease transmission

• Identifying and determining spatial and geographic patterns

3. Studying Disease Burden

• Reporting on morbidity, disability, injury, and mortality

• Identifying and analyzing social, spatial and geographic disparities

4. Health Policy, Planning and Services

• Aid the planning and development of health services and programs

• Provide administrative and planning data

• Provide foundation for public health measures and policies

Epidemiological Triangle 

• Agent may be a disease-causing bacterium or virus

• Host is a susceptible human being 

• Environment includes the means of transmission by which the agent reaches the host (e.g. contaminated air, water, or food)

Telemedicine

refers to the use of videoconferencing for medical care 

Health services for Indigenous populations

• European way of life excluded indigenous people from their culture and disconnecting them from traditional ways of living 

• Services may not be well oriented towards the communities’ needs

Health and safety at work 

we all have rights we should know about while working:

• Right to know about work related hazards

• Right to participate in health and safety 

• Right to refuse

what was the Lalonde Report ?

1974 report emphasized the need to look beyond the care of the sick in order to improve the health of the population

what was the Ottawa charter ?

In 1986, states that for health promotion states: that Canada should attempt to reduce inequities, to increase the prevention effort, and enhance people’s capacity to cope

The system defends the population against health threats: 

• physicians identify threats by participating in surveillance systems that identify threats early, for instance the notifiable disease system 

Protection against the financial consequences of ill health:

• physicians tailor their advice to the patients financial resources and situation

Proving equitable access to people centred care: 

• physicians ensure that most in need of health care

• Have the access they need 

when does epidemics occur?

see a number/rise of new cases much higher than normally would be seen 

Three essential characteristics of epidemiology 

• person (who)

• place (where)

• time (when)

Two Broad Types of Epidemiology 

framed under the mantle of descriptive and analytic epidemiology 

Descriptive epidemiology 

examining the distribution of a disease in a population, and observing the basic features of its distribution in terms of time, place and person 

Analytic epidemiology

testing a specific hypothesis about the relationship of a disease to a putative cause, by conducting an epidemiologic study that relates the exposure of interest to the disease of interest.

What is a Chronic Disease?

defined broadly as conditions that last 1 year or more

Epidemiology and the causes of chronic disease 

The best hope for protecting the public against these diseases is to learn how to

prevent them, or at least how to delay their onset. Ex. Cancer, heart disease

Heart disease 

Since the 1920s, has been the leading cause of death in the United States for both men and women.

Framingham Heart Study **

What do we mean by Infectious Disease? 

communicable and infectious ….is one caused by transmission of a specific pathogenic agent to a susceptible host 

Defining disease 

we need to define the disease in a very clear way so that there is no doubt about whether an individual case should or should not be counted

“Exposures” Health determinants:

underlying factors or social and physical conditions that impact health and disease 

Risk factors

lifestyle or environmental factors that increase risk of disease 

Disease frequency

In measuring, it is necessary not only to count the number of cases but to relate that number to the size of the population being studied

Incidence

it is the rate new cases of a disease in a defined population over a defined period of time 

prevalence

includes new cases AND pre-existing cases

How do we do Epidemiology?

Perform a Study 

What are kinds of epidemiological studies ?

Meta analysis & systematic review

Meta analysis

Takes all different kind of studies and combines it together, requires many different studies to be conducted

Systematic review

Review evidence, and many different studies of the same topic

Intervention studies

Usually done to test a new treatment for a disease

○ E.g. chemotherapy drug for cancer, or a preventive measure, such as a vaccine. 

Terminology of clinical trials 

the control group may be given a placebo— an active substance similar in appearance to the drug or vaccine being tested 

Randomized

means that each subject is assigned to the treatment group of the control group at random

Double blinded

means that both the patient and the doctor are blind as to whether the patient is receiving the drug or a placebo 

Observational studies

most epidemiological questions of interest cannot be assessed through an experimental design 

• involves cohort studies or case control studies