question

Public Health

answer

The standard definition applied to society at large; an organized effort aimed at reducing mortality and morbidity while improving the health of populations

question

Standard definition of Health

answer

A state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity (WHO, 1948)

question

Disease

answer

a scientific construct referring to a medical syndrome involving clinically identifiable and measurable signs and symptoms reflecting a biological pathology

question

Defining Public Health - C.E.A. Winslow

answer

1920 - science and art of preventing disease, organized community efforts, birthright of health and longevity

question

Defining Public Health - IOM

answer

1988 - "Public health is what we as a society do collectively to assure the conditions for people to be healthy."

question

Defining Public Health - WHO

answer

"Public health refers to all organized measures (whether public or private) to prevent disease, promote health, and prolong life among the population as a whole. Its activities aim to provide conditions in which people can be healthy and focus on entire populations, not on individual patients or diseases."

question

Core Functions of Public Health

answer

Assessment Policy Development Assurance

question

Assessment

answer

Every public health agency regularly and systematically collect, assemble, analyze, and make available information on the health of the community, including statistics on health status, community health needs, and epidemiologic and other studies of health problems

question

Policy Development

answer

Every public health agency exercise its responsibility to serve the public interest in the development of comprehensive public health policies by promoting the use of scientific knowledge base in decision-making about public health and by leading in developing public health policy - agencies must take a strategic approach, developed on the basis of a positive appreciation for the democratic political process

question

Assurance

answer

Public health agencies assure their constituents that services necessary to achieve agreed upon goals are provided, either by encouraging action by other entities, by requiring such action through regulation, or by providing services directly - this includes policymakers, and assurance of high-priority health services for those unable to afford them

question

Epidemiology

answer

The study of the distribution and determinants of health and disease, injuries, disability, and mortality in populations

question

Key characteristics of Epidemiology

answer

- population focus - distribution - determinants - outcomes - quantification - control of health problems

question

Population Focus

answer

Epidemiology is sometimes called population medicine - the population approach contrasts with clinical medicine's concern with the individual

question

Population

answer

All the inhabitants of a given area considered together

question

Epidemiology vs. Clinical Medicine

answer

Epidemiology - populations - studies/assessments - prevention - evaluation - planning Clinical Medicine - individuals - diagnosis - treatment - curing - caring

question

Distribution

answer

The occurrence of diseases and other health outcomes varies in populations., with some subgroups of the populations more frequently affected than others - answers: Who? When? Where? - person(s), place, time

question

Determinants

answer

Any factor that brings about change in a health condition or other defined characteristic; test hypotheses - ex: biologic agents

question

Exposures

answer

pertain to either the contact with a disease-causing factor or to the amount of the factor that impinges upon a group of individuals

question

Outcomes

answer

All the possible results that may stem from exposure to a causal factor - expressed as types and measures of morbidity and mortality

question

Morbidity

answer

illness due to a specific disease or condition

question

Mortality

answer

death

question

Control of Health Problems

answer

epidemiology helps with health promotion, alleviation of advises health outcomes, and prevention of disease - examples of health problems: infectious and communicable diseases, and chronic diseases

question

Quantification

answer

Counting the cases of illness or other health outcomes - denotes the use of statistics to describe the occurrence of health outcomes and measure their association with exposures

question

Common Assumptions of Epidemiology

answer

- human disease does not occur at random - human disease is causal and preventative factors that can be identified through systematic investigation of different populations or subgroups of individuals within a population in different places or at different times

question

Natural history of disease

answer

the course of a disease from its beginning to its final clinical endpoints - three types of prevention from a public health standpoint are Primary (before the disease occurs), Secondary (during progression of disease), and Tertiary (during later stages of the disease)

question

Primary Prevention

answer

Actions taken to reduce risk and avoid health problems before they start - health status: healthy - without signs and symptoms of disease, illness or injury

question

Secondary Prevention

answer

Actions taken that lead to early diagnosis and prompt treatment of a disease, illness, or injury to limit disability, impairment, or dependency - health status: disease, illness or injury

question

Tertiary Prevention

answer

actions taken to treat, rehabilitate, or minimize complication from a disease, illness, or injury - health status: disability, impairment, or dependency

question

Hippocrates

answer

- 5th century B.C. - ON AIR, WATER, AND PLACES - father of medicine; credited with departing from superstitious reasons for disease outbreaks - first epidemiologist - observed that different diseases occurred in different places - holistic approach - noted that malaria and yellow fever most commonly occurred in swampy areas - introduced terms like epidemic and endemic

question

Paracelsus

answer

Considered one of the founders of TOXICOLOGY - dose-response relationship - developed notion of target-organ specificity of chemicals, finding that toxic substances do not affect all organs to the same extent - laid groundwork for the field of chemotherapy

question

Dose-response relationship

answer

States that the effect of a toxic substance on the body is directly related to the strength of the dose - this is one of the major ways that epidemiologists today determine causal relations between exposures and outcomes

question

John Graunt

answer

- 1662 - First to employ quantitative methods - the columbus of statistics - developed and calculated life tables - divided deaths into 2 causes: acute (sudden) and chronic (long period of time)

question

Thomas Sydenham

answer

- believed observation should drive the study of the course of disease - the english Hippocrates in terms of holistic approach - described and distinguished different diseases including some psychological maladies - founder of clinical medicine - one of the first to identify scarlet fever and differentiate it from measles - advanced useful treatments and remedies including exercise, fresh air, and a healthy diet, which other physicians rejected at the time - observations, study of the course of disease, very detailed and really advanced useful treatment including natural remedies

question

Bernardino Ramazzini

answer

- 1690; 1695 - Outbreaks: lathyrism & malaria - founder of occupational medicine - considered chemicals, dust, metals, repetitive or violent motions, and unnatural postures - Lathyrahsm - wrote first comprehensive book on occupational diseases in which he outlined health hazards - led to modern perspective of considering work when assessing overall health

question

Percival Pott

answer

- 1775 - first to describe environmental cause of cancer - observed that chimney sweeps had high incidence of scrotal cancer - Chimney Sweepers' Act of 1788 - First link between epidemiology and public policy

question

James Lind

answer

- 1754 - first clinical trial by comparing groups of patients with citrus fruit related to scurvy - led British navy to require sailors to include limes or lime juice to their seamen.

question

Edward Jenner

answer

- 1796 - developed method for smallpox vaccination - variolation - father of immunology - smallpox considered only disease eradicated - acted sole on observation (cowpox related to smallpox)

question

Variolation

answer

introducing weaker strains of a disease in order to prevent people from stronger strains

question

Smallpox

answer

only infectious disease considered to be totally eradicated - last case: september 11th, 1977

question

William Farr

answer

- 1838 - routinely compiled the number and causes of death for over 40 years - appointed "compiler of abstracts" in England - applied vital statistical data to the public - developed more sophisticated system for coding medical conditions - believed in the miasma theory of disease - prompted idea that some diseases, especially chronic, may have multifactorial etiology

question

Multifactorial Epidemiology

answer

many factors contributing to the development of a disease

question

John Snow

answer

- 1854 Father of Epidemiology - used descriptive info provided by William Farr to formulate hypothesis to determine origin of cholera epidemic of the Thames River - his study of cholera was important because it was one of the first to be studied by epidemiologic methods

question

Cholera

answer

- untreated can kill more than 50% of infected people - level of fatality is often less than 1% when disease is treated

question

Miasmatic Theory of Disease

answer

- theory that disease was transmitted by a "miasma" or cloud that hung low on the surface of the earth

question

Snow's Natural Experiment

answer

Cholera outbreak of 1852 - residents served by Lambeth water company had fewer cases of cholera than those served by other water companies

question

John Snow's contributions

answer

- powers of observation and written expression - application of epidemiologic methods (used mapping and data tables - recommended a public health measure to prevent disease - Father of modern epidemiology

question

Ignaz Semmelweis

answer

- 1846 - observed that in the maternity ward, women who were delivered by established OB's were dying at a faster rate than those who were delivered by residents - identified the importance of hand washing to prevent disease

question

Germ Theory of Disease

answer

- every disease has a specific cause and control

question

Robert Koch

answer

- 1876 - used photography to see that microbes exist and are causing disease - showed that Anthrax was transmissible and reproducible in experimental animals

question

Koch Postulates

answer

1. The organism must be observed in every case of the disease 2. The organism must be isolated and grown in pure culture 3. The pure culture must, when inoculated into a susceptible animal, reproduce the disease 4. The organism must be observed in, and recovered from, the experimental animal

question

Louis Pasteur

answer

- 1861 - GERM THEORY - identified cause of rabies - investigated how sheep and humans contracted anthrax - showed that bacteria could cause disease - discovered how bacteria could be killed - anthrax vaccine

question

Modern Epidemiology

answer

caused shift in focus from acute infectious diseases to chronic lifestyle diseases

question

Janet Lane-Claypon

answer

- 1912 - first cohort in case-controlled studies - cohort study showing that babies fed breast milk gained more weight than those fed cows milk - developed first large case-control study investigating whether women with a history of breast cancer differed from women with no history - recognized that genes influenced cancer risk

question

Richard Doll & Austin Bradford Hill

answer

- 1950 - linked smoking with other serious diseases including lung cancer, coronary heart disease, and almost 20 other medical conditions - case-control studies assessing the association between smoking and lung cancer - eventually led to the U.S. Surgeon General's Report - Smoking and Health

question

Sir Michael Marmont

answer

- 1997 - Whitehall II Studies - Social determinants of health - conditions in which we are born, grow, work, live and age affect our health

question

Plagues Throughout the Centuries

answer

- 14th: leprosy - 15th: Plague - 16th: Syphilis - 18th (& 14th): Smallpox - 19th: scarlet fever, measles, and tuberculosis - 20th: Influenza and AIDS

question

What happened in 1793?

answer

The capital moved out of Philadelphia because of Yellow Fever - led to formation of the 1st board of public health

question

Descriptive Epidemiology

answer

refers to the epidemiological studies concerned with characterizing the amount and distribution of health and disease within a population - first step of epidemiological investigation - describes the distribution of disease through various characteristics including race, age, place, time, etc. - Person - who? (age, sex, race, occupation) - Place - where? (home, workplace, school) - Time - when? (onset of disease, exposure to infectious agent) - Clinical criteria - what? (burden of disease, how much exposure a person had)

question

Analytic Epidemiology

answer

Examines causal hypotheses regarding the association between exposures and health conditions - involves identifying and quantifying associations, testing hypotheses, and identifying causes of health-related states or events - answers: how? why?

question

Epidemiology Triangle

answer

Shows the interaction and interdependence of agent, host environment, and time as used in the investigation of disease and epidemics

question

Agent

answer

The cause of the disease - biological agents, chemical factors, physical, environmental, etc.

question

Host

answer

An organism (usually a human or animal) that harbors a disease - age, sex, race, religion, customs, genetic profile, occupation, marital status, family background, previous diseases, immune status

question

Environment

answer

includes those surroundings and conditions external to the human or animal that cause or allow disease transmission - temperature, altitude, crowding, housing, neighborhood, water, food, air, noise

question

Time

answer

accounts for incubation periods, life expectancy of the host or pathogen, and duration of the course of the illness or condition

question

Disease Transmission

answer

- direct (person to person) - indirect (common vehicle) - Vector-bone

question

Vector

answer

an invertebrate animal capable of transmitting an infectious agent among vertebrates

question

Reservoir

answer

The habitat (living or nonliving) on which an infectious agent lives, grows, and multiplies and is dependent on for its survival in nature - humans often serve as both reservoir and host

question

The Chain of Infection

answer

Pathogens -> Reservoir -> Mode of Transmission -> Host

question

Herd Immunity

answer

The proportion of people in a population who are resistant to a disease - when herd immunity occurs, the disease has no chance to take hold because most people are immune

question

Incubation Period

answer

The interval from receipt of the infection to the time of onset of clinical illness - time needed for the organism to replicate sufficiently until the infecting organism reaches the critical mass needed for clinical disease to result - site in the body at which the organism replicates - dose of infectious agent

question

Case Definition

answer

A standard set of criteria - assures that cases are consistently diagnosed, regardless of where or when they were identified and who diagnosed the case

question

Case

answer

a person who has been diagnosed as having a disease, disorder, injury, or condition

question

Primary Case

answer

the first disease case in a population

question

Index Case

answer

The first disease case brought to the attention of the epidemiologist -- ** index case is not always the primary case

question

Secondary Case

answer

those persons who become infected and ill after a disease has been introduced into a population and who become infected from contact with the primary case

question

Different levels of diagnosis

answer

suspect vs. confirmed

question

Suspect

answer

an individual who has all of the signs and symptoms of a disease or condition, but not yet diagnosed

question

Confirmed

answer

As more information becomes avail to the physician, he/she can upgrade the diagnosis - when all criteria meet the case definition

question

Endemic

answer

a disease or infectious agent usually present in a community, a geographic area, or population group - what we would expect to see in a given situation - ex: malaria is an endemic in 106 countries

question

Epidemic

answer

the occurrence in a community or region of cases of an illness, specific health-related behavior, or other health-related events clearly in excess of normal expectancy

question

Common Source Epidemics

answer

occur when there is a pronounced clustering of cases of disease that occurs within a short pored of time due to the exposure of persons or animals to a common source of infection (such as food or water) - tend to be more rapid than propagated epidemics - divided into 2 categories: point (quickly) vs. continuous

question

Propagated Epidemics

answer

- arise from infections being transmitted from one infected person to another - transmission can be through direct or indirect routes - host-to-host epidemics rise and fall more slowly than common source epidemics

question

Mixed Epidemics

answer

- occurs when a common source epidemic is followed by person-to-person contact and the disease is spread as a propagated outbreak

question

Pandemic

answer

an epidemic occurring worldwide, or over a very wide area, crossing international boundaries, and usually affecting a large number of people - ex: the 1918 influenza epidemic (Spanish Flu)

question

Common Interventions

answer

- interrupt the transmission - vector control/ personal hygiene

question

Chronic Disease Epidemics

answer

infectious diseases are no longer the leading cause of death in industrialized nations so a more advanced model of the triangle of epidemiology has been proposed that better reflects the behavior, lifestyle, and chronic disease issues found in modern times

question

Leading Causes of Death (1900 vs. 2008)

answer

1. Pneumonia/influenza vs. heart disease 2. Tuberculosis vs. Cancer 3. Diarrhea vs. chronic low respiratory disease

question

Epidemiologic Transition

answer

shift from acute, contagious disease to chronic and non-contagious ("lifestyle") diseases

question

Reason for Epidemiologic Transition

answer

- medical technology - improved standard of living - birth control - improved nutrition - sanitation and vector control - improvements in lifestyle

question

Fixed Population

answer

population that is permanent; always defined by a certain life event - Ex: people who were exposed to bomb of Hiroshima (they were there at a specific time, cannot be added to that population if you did not experience that specific event)

question

Dynamic Population

answer

o Steady-state o Inflow (immigration, births) o Outflow (emigration, death)

question

Rates

answer

measure of the frequency with which an event occurs in a defined population in a defined time o Tell us how fast a disease is occurring in a population o Ex: The number of cases of measles in Fairfax County in 2012

question

Ratio

answer

used to compare the occurrence of a variable in two different groups, neither of which is included in the other o Ex: males receiving HPV immunization/ Females receiving HPV immunization o Often compares two rates o Groups may be independent or related

question

Proportion

answer

type of ratio in which the numerator is a subset of the denominator o Tell us what fraction of the population is affected o Ex: males receiving HPV immunization/ all individuals immunized

question

Prevalence

answer

the proportion of the population with a disease risk factor or disease at a particular point in time - tells us the extent of the disease within the population of interest - (number of existing cases at a specified time)/(total population at specified time)

question

Point Prevalence

answer

the prevalence of a disease in a population at a single point in time

question

Period Prevalence

answer

the prevalence of a disease in a population over a specified period of time (thus it includes the cases at the start of the period and any subsequent new cases) - period prevalence = point prevalence + incidence

question

Incidence

answer

the number of new cases of a disease that occur during a specified time in a population at risk for the disease (number of new cases of a disease occurring in a population during a specified time)/(number of persons at risk of developing the disease during that period of time)

question

Prevalence is Increased by

answer

o Longer duration of a disease o Prolongation of life of patients without care o Increase in new cases (greater incidence) o In-migration of cases o Out-migration of healthy people o In-migration of susceptible people o Improved diagnostic facilities (better reporting)

question

Prevalence is Decreased by

answer

o Shorter duration of the disease o High case-fatality rates from the disease o Decrease in new cases (incidence) o In-migration of healthy people o Out-migration of cases o Improving cure rates of disease

question

Attack Rate

answer

synonymous with incidence in relation to food-borne outbreak

question

Person-years

answer

• Allows for measurement of long-term disease processes in dynamic populations • Incidence can be reported in terms of person-years • For example: "The incidence of the disease was 12.6 per 1000 person-years in our study population." • This could represent: o 100 people for 10 years (100 x 10 = 1000) o 1000 people followed for 1 year (1000 x 1 = 1000) o many people followed for various lengths of time

question

Relation between Incidence and Prevalence

answer

• Prevalence = (incidence rate) x (average duration) o When disease prevalence is low and incidence and duration remain stable over time o Population is steady

question

Issues with Morbidity Data

answer

Problems with numerators: o How do you define the disease? o How do you find the cases? Problems with denominators: o How do we classify groups? Problems with hospital data: o Admissions may be selective o Not designed for research o Populations at risk are not well-defined

question

Nazi Research Abuse

answer

o 16 German physicians practiced unethical medical experiments on Jews, gypsies, political prisoners o In 1947, the Nuremberg Code was written to protect research participants o The German physicians were convicted for crimes against humanity under this code o Led to standards in research requiring participants to participate voluntarily and are informed of risks

question

Tuskegee Syphilis Study (1932- 1972)

answer

• Public Health Service, working with Tuskegee Institute to record the natural history of syphilis in black men • No informed consent • Participants were told they were being treated for "bad blood" • Penicillin treatment became available in 1947 but researchers did not offer it to the participants

question

Milgram Obedience Studies

answer

• Shock experiment • Learner vs. teacher (unsuspected subject) • Milgram's question: are we capable of harming others under authority?

question

Willowbrook Hepatitis Study (1963-1966)

answer

• Intellectually disabled children were deliberately infected with hepatitis • Rationale was that these children were likely to contract the disease because of the institutional environment so controlled infection was better • Purpose of this study was to study the history of disease when left untreated • Willowbrook became overcrowded during the course of the study and would only admit children if their parents agreed to the child's participation in the study o Thus, the parents were coerced

question

Stanford Prison Study (1971)

answer

• Investigated the cases of conflict between guards and prisoners • Randomly assigned to roles and situated in a mock prison • Guards enforced authoritarian measures and abused prisoners • Many prisoners accepted the abuse • Study stopped early because of well being concerns

question

The Belmont Report

answer

• Boundaries between biomedical and behavioral research and accepted practice of medicine • The role of assessment of risk-benefit criteria in the determination of the appropriateness of research involving human participants • Appropriate guidelines for the selection of human participants for participation in research • The nature and definition of informed consent in various research settings

question

Basic Ethical Principles

answer

• Respect for persons • Beneficence • Justice

question

Respect for Persons

answer

• Individuals should be treated as autonomous agents • Persons with diminished autonomy are entitled to protection • Some persons are excluded from research activities that may cause them harm • Enter the research voluntarily • Are given adequate information to make an informed decision

question

Informed Consent

answer

respect the persons requires that participants, to the degree that they are capable, be given the opportunity to chose what shall or shall not happen to them - comprehensiveness - Voluntariness - information

question

Assent

answer

If the study includes children under 18, the child's parent or guardian will be responsible for giving the informed consent to participate

question

Beneficence

answer

• Obligation to research participants o Do not harm o Maximize possible benefits o Minimize possible harms • Risk- possibility that harm might occur o Chance or probability o Magnitude of severity • Benefit - something of positive value related to health or welfare • Balance between the two

question

Justice

answer

• Selection of participants scrutinized to see why some classes are systematically selected o Easy access o Compromised positions o Manipulability • Must select for reasons directly related to the problem studied • Publically funded research benefits are provided to everyone not just to those who can afford them • Do not unduly involve persons from groups unlikely to be among the beneficiaries of the research • Researchers must be fair in how they select participants o Not offer beneficial research to some patients while offering "undesirable" people risky research o Social justice - what classes of people are selected? • Some groups may be overburdened

question

Vulnerable Populations

answer

• Pregnant women • Human fetuses • Neonates (babies) • Prisoners • Children

question

Institutional Review Board (IRB)

answer

Federally required to oversee all research activities at colleges, universities and other organizations conducting research with human participants o How they accomplish goals: • Risk to subjects are minimal • Risk to subjects are reasonable in relation to anticipated benefits • Selection of subjects is equitable and fair • Informed consent is sought from each subject or his/her legal representative • Informed consent is appropriately documented • When appropriate, the research plan makes provisions for monitoring data collection • Privacy and confidentiality of research subjects are appropriately protected • Written approval must be obtained before research project begins • Additional training on the laws and the requirements for conducting ethical research is also required by most institutions

question

Life Expectancy

answer

The probable number of years a person will live after a given age, as determined by mortality in a specific geographic area. It may be individually qualified by the person's condition or race, sex, age, or other demographic factors.

question

U.S. Average Life Expectancy

answer

81.3

question

Global life expectancy

answer

70

question

Mortality Data

answer

• Pinpoint differences in risk • Disease severity • Treatment effectiveness • Surrogates for incidence • Health and well-being of a nation o Infant mortality

question

Measures of Mortality

answer

• Crude mortality rate • Cause-specific mortality rate • Case-fatality rate (CFR) • Proportionate mortality rate (PMR) • Years of Life Lost (YLL)

question

Crude Mortality Rate

answer

- (Number of deaths from all causes)/(number of persons in the total population) - unit is per number of people

question

Adjusted Mortality Rate

answer

Two ways: - direct standardization - indirect standardization - Ex: adjusting mortality rates for age

question

Direct Standardization

answer

method for adjustment - requires that we select a standard population first

question

Indirect Standardization

answer

method for adjustment - used when the age-specific death rates are unavailable - using the indirect method results in the calculation of the standard mortality ration (SMR)

question

SMR

answer

Standard Mortality Ratio - (# of observed deaths per year)/(# expected deaths per year)

question

Cause-specific Mortality Rate

answer

Allows us to evaluate death rates related to a particular disease or condition - (# of people who died from cause of interest)/(total population during the time period)

question

Case Fatality Rate

answer

CFR - (# of deaths from a specific cause)/ (# of individuals in the population with a specific disease) - expressed in a percent

question

Proportionate Mortality Rate

answer

PMR - (number of deaths from a particular cause)/(total number of deaths in the population) - expressed as percent

question

Years of Life Lost

answer

YLL - reflects the concept that death occurring at a younger age results in greater loss of future productivity than would death at a later age - this means, that the younger the age at which death occurs, the more potential years of life are lost - calculated by using individual level data or group level data - each individual YPLL can be calculated by subtracting the person's age at death from the reference age, which is the standard life expectancy for the general population of interest

Epidemiology Midterm – Flashcards

Unlock all answers in this set

Haven't found what you were looking for?

Search for samples, answers to your questions and flashcards