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Flashcards in Public Health and epidemiology Deck (62)
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1
Q

What is public health?

A

The science of protecting and improving the health of people and their communities. This work is achieved by promoting healthy lifestyles, researching disease and injury prevention, and detecting, preventing and responding to infectious diseases

2
Q

What is epidemiology?

A

The branch of medicine which deals with the incidence, distribution, and possible control of diseases and other factors

The study of distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems

3
Q

What are the determinants of health?

A
  • income and social status
  • social support networks
  • employment and work conditions
  • physical environment
  • education
  • healthy child development
  • Biology and genetic endowment
  • health services
  • personal health practices and coping skills
4
Q

Differentiate physician/veterinarian and epidemiologists

A

-A physician or veterinarian is concerned with the health of the individual whereas an epidemiologist is concerned with the health of the population overall

5
Q

What are the components of epidemiology?

A
  • occurrence of disease
    • surveillance
  • distribution of disease
  • determinants
  • control/prevention
6
Q

Describe what is the prevelance of a disease

A

A statistical concept referring to the number of cases of a disease that are present in a particular population at a given time

  • Proportion of disease affecting a population
  • Compares # of people with condition to total # studied
  • tells you widespread it is = usually a fraction, percentage or # of cases per 1000/ 10,000/100,000
  • prevalence of data can help identify and target at-risk populations
7
Q

What factors INCREASE prevalence?

A
  • longer duration of the disease
  • prolongation of life of patients without care
  • Increased in new cases(increase in incidence)
  • In-migration of cases
  • Out-migration of healthy persons
  • In-migration of susceptible people
  • improved reporting
8
Q

What factors DECREASE prevelance?

A
  • shorter duration of the disease
  • high case fatality rate from disease
  • Decrease in new cases (decrease in incidence)
  • In-migration of healthy people
  • Out-migration of healthy people
  • out-migration of cases
  • improved cure rate of cases
9
Q

What is the incidence of a disease?

A
  • Measure of the probability of a given medical condition in a population in a specific period of time
  • Tells you about the risk of acquiring it
10
Q

What are the factors affecting incidence rate?

A
  • New risk factors
    • Oral contraceptives as exposure and increase in thrombo-embolism in women
    • Food additives and cancer
    • New virus( HIV and AIDS)
  • Changing habits
    • Increased smoking and development of lung cancer
    • Fluoridated water and decrease I’m dental caries
11
Q

What is mortality?

A

The incidence of death

12
Q

What are the applications of mortality?

A

Applications of the darts include:

  • Analyze characteristics of those dying: identify high mortality areas
  • Enables appropriate responses and resources
  • determine life expectancy
    • compare mortality trends with other countries
    • Looking at the Global Burden of disease
13
Q

Give examples of mortality rates

A
  • Crude mortality rate
    • Counts all deaths
      • All causes
      • All ages and both sexes
    • Denominator includes entire population
      • All ages and both sexes
  • Cause specific mortality
    • Rate at which deaths occur for a specific cause
  • Age specific mortality rate:
    • counts only deaths in specific age group
      • Usually calculated for children less than 5 years of age
    • Denominator includes only persons in that age group
14
Q

What factors influence death rates?

A

Increase in deaths is due to:

  • Poor medical facilitates E.g. clinics, hospitals etc.
  • Poor sanitation
  • Poor hygiene and lack of clean water
  • Natural disaster eg hurricanes, earthquakes, droughts, floods
  • Limited education
  • War
  • Diseases eg AIDS
  • famine severe drought
15
Q

Explain the mortality rates that aren’t really rates

A

Live births as the denominator instead of actual group in which deaths are counted

  1. Infant mortality rate
    - counts deaths in children less than 12 months of age, divides the number of live births in same time period
  2. Maternal mortality rate
    - counts deaths in women due to pregnancy or childbirth, divides by number of live births in same time period
  3. Under-5 mortality rate
    - counts deaths in first 5vyears of life, divides by number of live births in the hypothetical cohort of newborns
16
Q

What is morbidity?

A

The rates of disease in a population

-measured by incidence and prevalence

17
Q

What are the applications of morbidity?

A
  • estimation of mortality
  • compare trends
  • impact of interventions(education; vaccines; new treatments)
  • focus funds and resources
18
Q

Contrast morbidity and mortality

A

Morbidity- proportion of illness in a population

Mortality- incidence of deaths in a population

19
Q

What is public health surveillance?

A

Public health surveillance is the continuous, systematic collection, analysis and interpretation of health data needed for the planning, implementation, and evaluation of public health practice

20
Q

What are the functions of surveillance?

A
  • serve as an early warning system fir impending public health emergencies
  • Document the impact of an intervention, or track progress towards specified goals
  • Monitor and clarify the epidemiology of health problems, to allow priorities to be set and to inform public health policy and strategies
21
Q

At what level does the methodology of surveillance occur?

A

Occurs at various Levels:

  • local
    • ministry of health

-State

  • National
    • public health service (UK)
  • International
    • CDC( Control for diseases and prevention and control)
    • ECDC (European Centre for disease prevention and comtrol)
    • WHO ( world heath organization)
22
Q

What are the applications of surveillance data?

A
  1. Qualification of major health risks
  2. Monitoring and recording natural history of a disease
  3. Detecting outbreaks and epidemics
  4. Basis for research
  5. Initiation of interventions (education, vector-control etc)
  6. Deciding where to spend money
23
Q

What are the types of surveillance?

A

Passive surveillance

Active surveillance

24
Q

What is active surveillance?

A

When a health department is proactive and contacts health care providers or laboratories requesting information about diseases. While this method is more costly and labor intensive, it tends to provide a more complete estimate of disease frequency

25
Q

What Is passive surveillance?

A

Health care providers report notifiable on a case-by-case basis. Passive surveillance is advantageous because it occurs continuously, and it requires few resources. However, it is impossible to ensure compliance by health care providers; moreover, cases occurring in people without access to care will frequently go unreported. Consequently, passive systems tend to under-reported disease frequency

26
Q

What are noticeable diseases?

A

A specified list of noticeable diseases- diseases that health care providers and/or labs and hospitals are required to report to the state

27
Q

Why we do notifiable disease surveillance?

A
  • detect disease when and where it happens
  • stop disease before it spreads
  • study disease to strengthen the science
  • improve how we prevent and control disease
  • keep people healthy
28
Q

What is the surveillance loop?

A

Objectives —> data analysis —> information —> action—> evaluation —> objectives

29
Q

What are the 5 Ws of epidemiology?

A
  1. What = health issue of concern
  2. Who= person.
  3. Where = place
  4. When = time
  5. Why/how= causes, risk factors, modes of transmission
30
Q

Explain the “What”- issue of concern of epidemiology

A

Infectious disease

  • transmissible
    • Type of outbreak
      • Endemic
      • epidemic
      • pandemic
  • Non-transmissible
  • Non-infectious disease
  • lung cancer
  • diabetes
  • heart disease
31
Q

What does endemic mean?

A

Infection is constantly maintained at a baseline level in a geographic area without external inputs

32
Q

What dies epidemic mean?

A

Rapid spread of infectious disease to a large number of people in a given population with8n a short period of time

Cases usually presumed to have a common cause or related to each other in some way

33
Q

What is a pandemic ?

A

Epidemic of disease that has spread across a large region; for instance multiple continents, or even worldwide, usually affect8ng a substantial population

34
Q

Explain the “who-person” of epidemiology

A
  • characteristics of people
    • age, sex, ethnicity/race
  • biological characteristics(immune. Status)
  • acquired characteristics (marital status)
  • activities(job, leisure, drug/alcohol/tobacco use)
  • conditions (access to medical care, socioeconomic status)
35
Q

What is the “where” of epidemio?

A

Geographical isolation and extent of the disease

36
Q

What is the when 9f epidemiology?

A

The disease occurrence over time

37
Q

What is the How of epidemiology?

A

Causes, risk factors

38
Q

Give an example of analytical epidemiology

A

Hepatitis A outbreak

  • case-patients had eaten at specific restaurant 2-6 weeks before onset of illness
  • interviewed case-control patients to identify what they had eaten.
  • interviewed group of people who had eaten there but did not get sick (the control group)
  • 94% of case patients had eaten salsa compared to 39% of control
  • Green onion implicated as source
39
Q

What are the types of studies used in analytical epidemiology?

A
  1. Environmental

2. Observational

40
Q

What is an observational study?

A
  • exposure is under natural conditions
    • cohort study
    • case control study (this was the Hep. A and green onions example)

N. - cross-sectional study

41
Q

What is an environmental study?

A

Investigator determines the exposure

-e.g. clinical trial

42
Q

What are the types of infectious disease?

A

Emerging infectious diseases

Re-emerging infectious diseases

43
Q

What are emerging infectious diseases?

A

These are due to newly identified and previously unknown infectious which cause public health problems either locally or internationally

44
Q

What are Re-emerging diseases ?

A

These are those that are due to reappearance and increase of infections which are known, but had formerly fallen to levels so low that they were no longer considered a public health problem
-increasing in incidence relative to precious baseline

45
Q

What are the basic stages of disease emergence?

A

Introduction

Establishment

Adaptation to new host and dissemination/spread

46
Q

Explain the introductory phase of disease emergence

A

Introduction of agent into a new host population from reservoir:

  • environment
  • animal
  • humans
47
Q

What are the contributing factors of emergence and re-emergence?

A
  • travel and commerce
    • fast travel, more remote areas, wider exposure to foods and vectors

-economic development and land use

  • failures in public health measures
    • e.g. reduction in vaccine coverage
  • global warming/climate change
    • climate changes habitat for e.g, vectors
  • human demographics and behavior
    - overcrowding; mega-cities ; poverty

Microbial adaptation and change
-mutations, gene transfer (antibiotic resistance , toxins, etc)

Deliberately emerging terrorism

48
Q

(Re)emergence=

A

Usually an interplay of multiple factors

49
Q

What microbial factors contribute to emergence/reemergence?

A
  • genetic adaptation and change

- polymicrobial infections

50
Q

What are the host related factors that play a role in emerging/re-emerging?

A
  • susceptibility
  • demographics and behavior
  • travel and trade
  • bioterrorism
  • occupational exposures
  • inappropriate use of antibiotics
51
Q

What are the environmental factors that contribute to emergence/reemergence?

A
  • climate and weather
  • land use
  • technology and industry
  • poverty and social inequality
  • lack of public health resources
  • animal population
  • war and famine
52
Q

Give an example of an emerging infection

A

Influenza pandemic

53
Q

What is an antigenic shift ?

A

Sudden emergence of a novel/new strain of virus

  • potential for epidemics and pandemics
    • if the strain then spreads human. —> human
54
Q

How can antigenic shift occur?

A
  • flu virus from ducks/ birds infects humans
  • flu virus from duck/birds infects intermediate host (pigs) and then infects humans
  • viruses from ducks/birds and humans recombine in a mixing vessel(usually pugs) and from there infect humans
55
Q

What is antigenic drift ?

A

Gradual change in composition of antigens on flu virus surface

56
Q

What are the contributing factors for re-emergence of dengue?

A

Decline of vector control programs

  • re-infestation
  • insufficient financial resources
  • rapid growth and urbanization of populations
    • poor sanitation
  • poverty
  • increased travel
  • presence of multiple stereotypes
  • climate change
57
Q

Give an example of a re-emerging infection

A

Dengue fever

58
Q

What causes decrease in community(herd) immunity?

A

A sufficient proportion of a population is immune to an infectious disease (through vaccination and/or prior illness ) to make its spread from person to person unlikely. Even individuals not vaccinated(such as newborns and those with chronic illness ) are offered some protection because the disease has little opportunity to spread in the community

59
Q

What are the communicable diseases that require quarantine?

A

Federal isolation and quarantine are authorized for these communicable diseases
-cholera

  • diphtheria
  • infectious tuberculosis
  • plague
  • small pox
  • yellow fever
  • viral hemmorhagic fevers (like Ebola)
  • severe acute respiratory syndrome ( SARS, NERS, COVID-19)
  • Flu that can cause a pandemic
60
Q

What 8s isolation?

A

Isolation separates sick people with a quarantinable communicable disease from people who are not sick

61
Q

What is quarantine?

A

Quarantine separates and restricts the movement of people who were exposed to a contagious disease to see if they become sick.

62
Q

How do isolation and quarantine help?

A

They help protect the public by preventing exposure to people who have or may have a contagious disease