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Epidemiology > Communicable Disease Prevention Exam > Flashcards

Communicable Disease Prevention Exam Flashcards

1
Q

Communicable disease

A
  • Contagious (transmissible/spread from person to person)
  • Not all infectious diseases
  • eg. Corona virus, HIV, flu
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2
Q

Infectious disease

A
  • All modes of transmission (e.g. includes vectors, food borne)
  • All communicable diseases
  • eg. Malaria, tetanus, food poisoning
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3
Q

Infectivity

A
  • Ability of an organism to infect a susceptible host
  • Measured by attack rate
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4
Q

Pathogenicity

A
  • Ability of an agent to produce disease
  • Measured by proportion of clinically apparent infection
    low/high
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5
Q

Virulence

A
  • Severity of the disease after infection occurred
  • Measured by case fatality rate
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6
Q

Immunogenicity

A

Ability to confer immunity after infection

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7
Q

Unapparent disease

A
  • Asymptomatic active infection/disease
  • Measured by lab test
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8
Q

Factors that determine impact

A

A. The characteristics of infectious agent
B. The characteristics of the host
C. The characteristics of transmission
D. The characteristics of the environment and its influence

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9
Q

Latency period

A

The time interval between when an individual or host is infected by a pathogen and when they become infectious (images in OneNote)

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10
Q

Incubation period

A

Incubation period is the time elapsed between exposure to a pathogenic organism and when symptoms and signs are first apparent (images in OneNote)

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11
Q

Reservoir

A

Any person, animal, arthropod, plant, soil, or substance, or a combination of these, in which an infectious agent normally lives and multiplies, on which it depends primarily for survival, and where it reproduces itself in such a manner that it can be transmitted to a susceptible host
Types of reservoir: Human reservoir, Animal reservoir, Non-living reservoir

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12
Q

Carrier

A

Carrier is an infected person or animal that harbors a specific infectious agent in absence of discernible clinical disease and serves as a potential source of infection to others
Types (image in OneNote): Convalescent, Healthy, Temporary, Chronic

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13
Q

Cases

A

Cases are persons with clinical disease
- Primary: person who brings the disease into the
population
- Index: the first case to be discovered by the healthcare
system during an outbreak
- Secondary: all cases infected by the primary case
- Tertiary: all cases infected by any secondary case
(Mild cases are more important sources of infection than severe cases)

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14
Q

Subclinical cases

A

Subclinical cases the disease agent multiply in the host but does not manifest by signs and symptoms. Dominant role in maintaining the chain of infection in the community

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15
Q

Zoonotic disease

A

An infectious disease that is transmissible under natural conditions from vertebrate animals to humans

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16
Q

Portal of exit

A

The path by which a pathogen leaves its host. This usually corresponds to the site where the pathogen can be localised (examples in OneNote)

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17
Q

Portal of entry

A

The path/route by which a pathogen enters a susceptible host. The route must provide access to tissues in which the pathogen can multiply or a toxin can act.

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18
Q

Bioterrorism

A

A bioterrorism attack as “the deliberate release of viruses, bacteria or other germs (agents) used to cause illness or death in people, animals, or plants”

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19
Q

Disease transmission

A

Direct contact, droplet, indirect contact (vector, vehicle and airborne)

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20
Q

Endemic

A

Endemic is the constant presence of a disease or an infectious agent in a population within a geographical area. Infection remains at a steady level. Often refers to usual prevalence.

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21
Q

Hyper endemic

A

Hyper endemic refers to persistent, high levels of disease occurrence

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22
Q

Sporadic

A

Sporadic refers to a disease that occurs infrequently or irregularly

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23
Q

Exotic

A

Exotic diseases are those that are imported into a country in which they do not naturally occur

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24
Q

Cluster

A

Cluster refers to an aggregation of cases grouped in place and time that are suspected to be greater than the number expected, even though the expected number may not be known, and they are not linked epidemiologically

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25
Q

Outbreak

A

Outbreak is a noticeable, often small, increase over the expected number of cases. Often used to describe
- Two or more related (epidemiologically-linked) cases of a
similar disease: food poisoning after party
- An increase in the observed incidence of cases over the
expected incidence within a given time period
- A single case of a serious disease: botulism, polio or
smallpox constitutes a public health emergency

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26
Q

Epidemic

A

Epidemic refers to an increase, often sudden, in the number of cases of a disease above what is normally expected in that population in that area. It’s like an outbreak but bigger area and less confined event (more info in OneNote)

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27
Q

Pandemic

A

An outbreak of a new pathogen that spreads easily from person to person across the globe (crosses international borders). Bigger than an epidemic

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28
Q

Reproduction number (R)

A

Reproduction number (R) is the average number of new infections caused by 1 infected individual. It is an indication of the pace of growth across successive generation of transmissions.
- Basic reproduction number (R0) is the reproduction number (R) when the entire population is susceptible
- When R>1 the epidemic progresses
- When R<1 the epidemic recedes (wanes) and the outbreak will eventually die out

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29
Q

Primordial prevention

A

Comprises risk factor reduction targeted towards an entire population through a focus on social and environmental conditions. Typically get promoted through laws and policy. Primordial and primary prevention are basically the same but primordial focuses on a large population groups such as ‘young people’ whereas primary prevention will be a bit more specific such as ‘university students’

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30
Q

Primary prevention

A

Directed toward the stage of susceptibility, before the pathogen establishes itself in the body; Goal is to prevent disease from occurring, reducing its incidence and prevalence in the community (vaccination)
Aim is to reduce incidence

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31
Q

Secondary prevention

A

Directed toward the subclinical stage (not yet symptomatic/ apparent) to reduce the expression or severity of the disease once it emerges. (anti-retroviral therapy asymptomatic HIV) [SCREENING]
Aim is to reduce prevalence

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32
Q

Tertiary prevention

A

Directed toward the clinical stage to prevent or minimize the progression of the disease (complication) or its sequelae (prevention of liver Cirrhosis in hepatitis B infection.)
Aim is to reduce long-term impairment

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33
Q

Control of communicable disease

A

Control of infectious diseases refers to the actions and program directed towards reducing new infections, reducing infections in the community at any given point in time, or completely eradicating the disease. Aims to reduce a disease incidence, prevalence, morbidity or mortality to a locally acceptable level
The four C’s of control
- Cases
- Contacts
- Carriers
- Community

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34
Q

Elimination

A

Reduction to zero of the incidence of a specified disease in a defined geographical area as a result of deliberate efforts; continued intervention measures are required.

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35
Q

Eradication

A

Permanent reduction to zero of the worldwide incidence of infection caused by a specific agent as a result of deliberate efforts; intervention measures are no longer needed

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36
Q

Extinction

A

The specific infectious agent no longer exists in nature or in the laboratory

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37
Q

Mortality rate

A

Mortality rates are the incidence rate of fatal cases in the total population at risk during a specified time period. The incidence rate of fatal cases is primarily determined via death certificates and registries
Mortality rate= incidence rate of fatal cases/ total population at risk

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38
Q

Morbidity rate

A

The morbidity rate (burden of disease measure) is the incidence rate of nonfatal cases of a disease in the total population at risk during a specified time period. The rate is calculated by identifying impairments, disabilities and handicaps within the population at risk.
- DALY= Years of life lost (YLL) + Years lost to disability (YLD)
- YLL = number of deaths (N) x standard life expectancy at age of death in years (L)
- YLD = number of incident cases (I) x disability weight (DW) x average duration of the case until remission of death (L)

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39
Q

Attack rate

A

The attack rate is used to outline the risk a disease caries. It provides valuable information on the rate at which a disease spreads, which is critically important for responding to it. The predominant attack rates used in epidemiology are the primary or overall attack rate, and the secondary attack rate. The overall attack rate indicates the proportion of individuals being infected by a communicable disease over a certain period of time. This is calculated by dividing the total number of new infections over a specified period of time, by the population number at the start of that time period. Alternatively, the secondary attack rate represents the proportion of people exposed to the disease which are infected. This is calculated by dividing the number of contacts newly infected by the total number of contacts. The secondary attack rate is usually represented through a percentage, so for a disease with a secondary attack rate of 20%, one in five susceptible people exposed to a case will be infected.

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40
Q

Incidence

A
  • Cumulative Incidence: takes into account the time periods each individual is disease-free, thus “at risk” of developing the disease. It is useful for assessing the impact of acute conditions
  • Incidence rate: a measure of the number of new cases (incidence) divided by the sum of the time that each member of the population is at-risk
    (equations in OneNote)
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41
Q

Prevalence

A

Prevalence is the number of existing cases of an outcome of interest and is expressed as a proportion or percentage.
- Point prevalence: Prevalence literally at one point in time (e.g. right now)
- Period prevalence: Prevalence measured over a (short) period of time (e.g. over the last year)
(equation in OneNote)

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42
Q

Relative Risk (RR)

A

Rate ratio (also know as: Risk Ratio or Relative risk) is a measure of disease frequency. It is calculated for prospective studies including randomised clinical trials and cohort studies, and cross-sectional studies.
- If the rate ratio is 1, it suggests no difference in risk.
- A rate ratio > 1 suggests an increased risk of that outcome in the exposed group.
- A rate ratio < 1 suggests a reduced risk in the exposed group.
(equation in OneNote)

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43
Q

Attributable Risk (AR)

A

The Attributable Risk (AR) or risk difference is a measure of the absolute difference between the two measures of disease frequency. AR focuses on the excess risk of disease in those who are exposed compared with those who are not exposed
(equation in OneNote)

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44
Q

Population Attributable Risk (PAR)

A

To calculate the PAR, we subtract the rate of the disease in the unexposed group from the rate of disease in the general population. This tells us the number of cases of disease that would be eliminated from the general population if the exposure were eliminated
(equations in OneNote)

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45
Q

Odds Ratio (OR)

A

An odds ratio is a statistic that quantifies the strength of the association between two events (a measure of association between an exposure and an outcome).
- If an odds ratio is 1, it means there is no association between the exposure and the outcome
- If the 95% confidence interval for an OR includes 1, it means the results are not statistically significant
(equation in OneNote)

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46
Q

Hazard ratios (HR)

A

Hazard ratios (HR) help measure the effects of an intervention on an outcome of interest over time. The outcome of interest may be positive (discharge/disease free) or negative (relapse/death). HR helps us understand how long it takes for a particular outcome to occur
(more info in OneNote on what the numbers mean)

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47
Q

Common source outbreak

A

Common source, where cases of disease arise from a single shared or ‘common’ source such as a batch of contaminated food, a contaminated water supply, industrial pollution or an infected food handler.
Includes:
a) Point source outbreak
b) Continuous common-source outbreaks
c) Intermittent common-source outbreaks

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48
Q

Propagated or progressive outbreak

A

Propagated or progressive is where the spread of disease is person to person

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49
Q

Point source outbreak

A

A point source outbreak is a type of common source outbreak in which the period of exposure to the infectious agent or toxin is brief and essentially simultaneous. Consequently, outbreaks are usually of short duration and all cases occur within one incubation period. All cases are exposed to the causal agent over a short period of time and all cases fall within the minimum and maximum incubation period. Incubation period varies among exposed individuals, reflecting differences in the intensity of exposures and/or differing immune responses among the exposed. The modal frequency typically correlates with the average incubation period. The distribution of data is commonly right-skewed, with the number of cases increasing rapidly, reaching a peak, and then gradually tapering off
(graph in OneNote)

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50
Q

Continuous source outbreak

A

A continuous source outbreak is a common source outbreak in which the period of exposure is continuous. Cases do NOT occur within the span of a single incubation period. The diagram to the right demonstrates a continuous source epidemic curve. Cases occur over multiple incubation periods as there is an ongoing source. The downward slope of the curve at the end may be very sharp of the common source is removed or a successful intervention is put into place
(graph in OneNote)

51
Q

Intermittent source outbreak

A

An intermittent source outbreak is a common source outbreak in which the exposure is intermittent. Cases do NOT occur within the span of a single incubation period. The pattern of the curve reflects the intermittent nature of the exposure, and the typical finding is intermittent clusters of cases with irregularly spaced peaks (see diagram below). Examples of intermittent outbreaks include industrial contaminants emitted at intervals contaminating food or water supplies. Or a series of outbreaks of food poisoning occurring at different summer camps for children. While the gaps between the outbreaks could initially suggest person-to-person transmission followed by an incubation period, the successive peaks do not become larger and merge as they would if the outbreaks were due to infectious spread.
(graph in OneNote)

52
Q

Propagated or progressive epidemics

A

Propagated or progressive epidemics occur when a disease that is transmitted from person to person is introduced into a susceptible population, leading to serial transmission. Secondary and tertiary generations can often be identified in the curve before simultaneity is lost. The diagram to the right demonstrates a propagated epidemic. The index case is isolated at the start. Secondary cases (infected by the index case) arise within one incubation period and, in turn, serve as sources for tertiary cases. Successively taller peaks occur, initially separated by one incubation period, but the peaks tend to merge into waves with increasing numbers in each generation. The epidemic continues until the number of susceptible individuals declines or until intervention measures take effect.
(graph in OneNote)

53
Q

Passive surveillance

A

In passive surveillance systems, medical professionals in the community and at health facilities report cases to the public health agency, which conducts data management and analysis once the data are received. Public health staff do not engage in identifying cases but rather assess data completeness and reliability of the reported cases. Passive surveillance likely misses cases due to the reporting structure but it requires less resources so it is often implemented.

54
Q

Notifiable disease surveillance

A

Notifiable disease surveillance is an example of passive surveillance. Notifiable diseases are classified as such because they are of public health importance: they can be a severe risk to human health, outbreak prone, considered to be an emerging or re-emerging disease, or have a timely intervention available for control of the disease. Countries mandate which diseases are notifiable

55
Q

Active surveillance

A

Active surveillance requires public health staff to engage actively in the system and take action in order to receive reports of disease cases. This may involve calling or visiting health facilities to encourage follow-up or having staff review medical records to identify cases meeting prescribed case definitions. Active surveillance aims to detect every case. Although active surveillance is more comprehensive, it requires significant human and financial resources. Active surveillance can have many approaches, including country-wide (e.g., for polio, measles, and rubella) or restricted to sentinel sites that capture cases within a demined catchment population

56
Q

Sentinel surveillance

A

A sentinel surveillance site is a single or small number of health facilities that are responsible for collecting data on cases enrolled with the case definition under surveillance including global networks surveying for diarrhea or pneumonia. Most sentinel sites do not have a predefined catchment population (or denominator to calculate incidence), and therefore data at these sites are simply numbers of cases (numerators). Sentinel site surveillance provides useful epidemiological information on proportions caused by different pathogens, age distribution, and risk factors and could also be used for monitoring trends of hospitalized cases within a health facility if health-care patterns and population have been stable. Furthermore, these data may be used in case–control studies to assess effectiveness of a vaccine or other preventive measures. Surveillance focused on one or a small number of surveillance sites often allows for gathering more data of higher quality.

57
Q

Population-based surveillance

A

With population-based surveillance, every appropriate health facility reports on the predefined diseases with the goal of identifying all cases in a specific geographic area. Population-based surveillance can either represent the whole country (national) or a defined subnational population area. Since the population is defined, these surveillance sites can produce rates of disease (for example, incidence and mortality rates), which allows for comparison of rates of disease between other population-based surveillance sites. Population-based surveillance is more costly than sentinel site surveillance, but produces more generalizable data on incidence of disease.

58
Q

Aggregate surveillance

A

Aggregate surveillance data can exist in a variety of forms, but the main feature is that it lacks detailed information on specific cases. Aggregate data typically include the number of cases (for example, number of suspect and confirmed neonatal tetanus cases, or by age group) for a specific region and time period. This information can monitor the number of cases but lacks the individual-level data required for specific analyses. An example of this is the Integrated Disease Surveillance and Response (IDSR) system which asks clinicians to report the number of cases of specific diseases.

59
Q

Case-based surveillance

A

Case-based surveillance refers to surveillance systems that collect information about each case at the individual level. This type of surveillance system has a case investigation form where information can be gathered from the patient or their family members, their medical records, and their laboratory records. At a minimum, more detailed information on person (who is infected), place (where they live, where they might have been infected), and time (when they became ill) is collected. A line list from this investigation form is created and reported up their normal reporting channels. In some scenarios, a case-based surveillance system might transition to aggregate as the number of cases becomes large as it overwhelms the system, like what happened during the 2009 H1N1 outbreak. In contrast, an aggregate surveillance system might become case-based temporarily in an outbreak to understand more of the epidemiology of the disease. Certain diseases, such as polio and measles, are recommended to be case-based.

60
Q

Syndromic surveillance

A

Syndromic surveillance involves monitoring cases that meet a clinical case definition for the disease under surveillance, typically without laboratory confirmation (Henning, 2004). This allows for rapid identification of a cluster of cases that might warrant further investigation. An example of syndromic surveillance includes acute fever/rash surveillance in many countries, which is used to monitor measles and rubella. The fever and rash could be due to a multitude of causes, and if there is an increase in the number of fever/rash cases reported, this could indicate an outbreak. As field investigations are ongoing, laboratory testing can be performed on some or all of the cases identified by syndromic surveillance to determine the etiology. In the acute fever/rash surveillance system, laboratory specimens might be collected to undergo testing for measles and rubella. A well-established global WHO-coordinated measles laboratory network provides support to monitoring measles cases and provide genotype information globally. Syndromic surveillance case definitions can be used in emergency or outbreak situations as an alert system to identify suspect cases that meet a broad case definition to then be further investigated. During the Ebola outbreak in 2014–15, airport security was increased to identify people with a fever and a history of travel to an Ebola-affected country in order to stop the disease from traveling between countries.

61
Q

Laboratory confirmed surveillance

A

In contrast, some surveillance case definitions are based on confirmed cases in a laboratory where the etiologic agent can be identified through a variety of laboratory tests (e.g., serology testing, bacterial culture, or molecular diagnostics) or at the bedside with well-validated commercial rapid diagnostic tests (e.g., malaria and Streptococcus pneumoniae). As an example, virologic influenza surveillance networks use laboratory-confirmed influenza to determine the circulating strains to provide information for vaccine composition. A critical objective of laboratory-based surveillance is to monitor for emerging drug resistance in pathogens or shifts in serotype distribution.

62
Q

Zoonotic surveillance

A

Zoonotic diseases cause disease in humans and can be challenging to control since both animals and humans can be hosts. Many zoonotic diseases of public health importance are covered in other articles of this encyclopedia, including West Nile Virus, avian influenza, Ebola (and other hemorrhagic fevers), Lyme disease, SARS, Nipah virus, and rabies. Historically, zoonotic and human disease surveillance existed separately, but there is a push to harmonize these systems to improve surveillance for diseases affecting both populations. Illness in one species might be a harbinger of illness in humans, and an integrated comprehensive surveillance system can help identify potential disease transmission that might be ongoing. For example, surveillance for Borrelia burgdorferi, the causative agent of Lyme disease, in the tick population can help public health authorities determine proper interventions to decrease the transmission from ticks to humans. One Health emphasizes the link of human health to the surrounding environment and animals. One of the mission statements of One Health is to improve the lives of all species by harmonizing both animal and human disease surveillance and control efforts. International organizations participating in One Health include WHO, the UN Food and Agricultural Organization, and the World Organization for Animal Health.

63
Q

Serosurveillance

A

Serosurveillance involves the use of blood specimens to determine the burden of disease or immunity gaps in a population. Serosurveillance is frequently done as a periodic survey for multiple diseases of interest simultaneously. However, serosurveillance cannot provide information in a timely manner; thus an outbreak might have occurred that is discovered by serosurveillance, but it might be potentially too late for an intervention to decrease disease transmission. Serosurveillance is sometimes the only type of surveillance conducted for an infectious disease. For example, hepatitis B is frequently asymptomatic in children, making evaluating the impact of vaccination efforts extremely challenging. The standard has become to perform serosurveillance among cohorts of vaccinated children to identify the burden of disease and determine the impact of vaccination efforts. In some countries, national health surveys, such as the National Health and Nutrition Examination Survey (NHANES) and Malaria Indicator Surveys, are conducted periodically and include a serologic component, allowing one to monitor trends in diseases and immunity over time. For example, NHANES includes data on hepatitis B, C, and D antibodies.

64
Q

Adverse events following immunization (AEFI)

A

Adverse events following immunization (AEFI) surveillance is a critical component of ensuring vaccine safety in the populations where the vaccines are being used. Surveillance often begins at the health facility level, where health workers are trained to recognize adverse events from immunizations, and is reported to national regulatory agencies and WHO. This surveillance is critical for investigating problems that could occur with bad lots of vaccines and mishandling of vaccines in the cold chain (improper storage) which can contribute to the public perception of the vaccine program.

65
Q

Disease notification

A
  • Urgent notifiable: immediate notification on diagnosis or clinical suspicion (e.g. measles, hepatitis A, rabies).
  • Routine notifiable: written notification within 5 days of notification (e.g. influenza, pertussis, buruli ulcer, syphilis)
66
Q

Steps of an outbreak investigation

A
  1. Prepare for field work
  2. Verify/establish the existence of the outbreak
  3. Confirm/verify the diagnosis
  4. Define and identify cases
  5. Describe / orient data (Person, Place, Time)
  6. Develop hypotheses
  7. Evaluate hypotheses
  8. Refine hypothesis / perform additional studies
  9. Implement control and prevention measures
  10. Communicate findings
67
Q
  1. Prepare for field work
A
  • Epidemiological knowledge & homework
  • Supplies & equipment
  • Team composition
  • Administrative
68
Q
  1. Verify the existence of an outbreak
A
  • Defined as “more cases than usual”
  • Must specify both community or region and time period precisely (person, place, time)
  • Must have methods in place to record “usual”/ “baseline” patterns of disease
  • Surveillance (passive, active and sentinel)
  • Source information
69
Q
  1. Confirm the diagnosis
A
  • Review clinical findings
  • Review laboratory results of cases
  • Be as specific as possible about the causative agent (“Outbreak strain” of bacteria / virus. May need specialised laboratory input)
  • Talk to cases
70
Q

Reference laboratories

A

Labs that confirm diagnosis and test for rarer diseases that other labs don’t test for

71
Q
  1. Define and identify cases
A

A case definition is a standard set of criteria for deciding whether an individual should be classified as having the health condition of interest.
- Confirmed- usually laboratory confirmed
- Probable - laboratory results not available
- ± Possible – often less stringent clinical criteria

72
Q
  1. Describe & orient the data
A
  • TIME: Draw an epidemic curve (number of cases on y-axis, time on x-axis, may provide hints about source of outbreak)
  • PLACE: Map the data
    PERSON: Explore data according to personal characteristics
73
Q

6-8: Develop / test / refine hypothesis

A

What is the source of the infection?
Case-control or cohort study? (more detail and application in the lecture)
Other investigations?

74
Q

Case-control study

A
  • A group of people with a disease and controls without the disease, looking at prevalence of past exposure.
  • Compute an odds ratios of exposure (estimate strength of association between source and disease)
  • Case-control good if:
    Clearly defined single outcome, rare disease
    Large population at risk of disease
    Multiple exposures to be examined
  • Potential problems with case-control:
    Choice of appropriate controls
    Recall bias for cases (incentive to remember)
    (diagram in OneNote)
75
Q

Cohort study

A
  • A group of disease-free people grouped by exposure status who are followed up over time to see who develops a disease/condition
  • Follow-up a group, exposed & unexposed
  • Can be used if source is known or strongly suspected so that all exposed individuals can be identified
    Can calculate attack rates for exposed and unexposed (to various exposures if necessary), and compute relative risks of getting disease in exposed vs. unexposed
    (diagram in OneNote)
76
Q

9: Control and prevention

A

Once source of outbreak has been identified, aim to break links in chain of infection
Do as soon as possible
Examples
* Remove contaminated food
* Sterilise contaminated water
* Spray mosquitoes / destroy breeding sites
* Isolation / treatment of cases
* Immunise contacts / susceptibles
* Prophylactic medication
* Behaviour modification

77
Q

10: Communicate findings

A
  • Must occur throughout outbreak investigation
  • Prepare timely reports
  • Clearly state facts
  • Manage outrage
  • Beware of legal implications
  • Aim to improve practice
78
Q

International Health Regulations (IHR)

A

Legal instrument that covers measures for preventing the transnational spread of infectious diseases
Requires all countries have the ability to:
* Detect
* Assess
* Report
* Respond
* Also includes specific measures countries
can take at ports, airports, ground crossings

79
Q

International Emergency Declaration

A

Under the International Health Regulations a Public Health Emergency of International Concern (PHEIC) is declared by WHO if the situations meets 2 of 4 criteria:
* Is the public health impact of the event serious?
* Is the event unusual or unexpected?
* Is there a significant risk of international spread?
* Is there a significant risk of international travel or trade restrictions?

80
Q

Role of national government

A
  • Acts on national priorities (Liaison and representation of country with international bodies)
  • Funding
  • Medicare, subsidy to private health
  • Pharmaceuticals (PBS)
  • Non specific grants (e.g. administration, welfare)
  • Direct specific (e.g. vaccine, testing, equipment)
  • Negotiation and coordination of policy development
  • Respond to event such as outbreak, bioterrorism, and
    those have potential for greater damage to economy
81
Q

Role of state government

A
  • Acts on regional priorities
  • Funds majority of hospital care (supplemented nationally)
  • Partly fund health related activity of local government
  • Surveillance, investigation and control
  • Synchronise activity with national
82
Q

Role of local government

A
  • Acts on local priorities
  • Role varies among jurisdiction (city/shire)
  • Generally operates under public health legislation on: Environmental issues, Food safety issues, Immunisation services, Crowding, Building design
  • Enforcement and execution of State and National policy
    decisions
83
Q

Communication components

A
  1. Creating a Public Health Crisis Communication Plan
  2. Understanding Legal and Healthcare Policies
  3. Planning for Crises
  4. What to Do When a Crisis Begins
  5. Identify Who Will Serve as a Spokesperson Regarding the Crisis
  6. Ease Public Panic
  7. Help Set the Tone for How People Will React
  8. Maintain Consistent Communication during a Crisis
  9. Working with Media to Effectively Communicate
  10. Wrapping up
84
Q

1 Crisis communication plan

A
  • Purpose is to protect the health
    and safety of citizens
  • Effect plan has a clearly defined
    audience
85
Q

2 Legal and healthcare policies

A
  • Not all information gathered may be available to media or public
  • Defence of the government is paramount, sensitive information must not be disseminated
  • However, transparency is a central component
86
Q

3 Planning for crisis

A

Broken down into the following phases:
* Pre-crisis: most critical planning work takes place in this phase
* Initial: Intense media and public interest on the rise, incomplete facts may be reported
* Maintenance: Helping the public understand the risk, listening to feedback, staying on top of information flows and correcting misinformation
* Resolution: Reinforce public messages, promote risk avoidance and mitigation education, and address mishaps in response efforts
* Evaluation: Assess plan performance, record lessons learned and determine actions to improve future planning

87
Q

4 When a crisis begins

A

First critical steps include the following:
* Verifying data is scientifically sound and validated by the medical community
* Notifying leaders, giving them the first assessments and informed insights on critical next steps
* Coordinating with government (all levels) to centralise communications
* Informing the media about the emergency through an official statement and monitoring for misinformation
* Sharing information with public directly
* Engaging with partners to let them know about response efforts and ask for support in communicating the right messages
* Conducting a public health crisis risk assessment and establishing a locale for centralised operations

88
Q

5 Identify spokesperson

A
  • Critical step in controlling the messaging
  • Their position should not be the only factor in selection
  • Communication skills – across media platforms
  • Demeanour
  • Trustworthiness
  • Availability
  • Understanding
89
Q

6 Ease public panic

A

Ease panic by:
* Clear and simple to understand information on the potential risk
* Steps people can take to help protect themselves
* Being transparent

90
Q

7 Set the tone for reactions

A
  • People will feel vulnerable, stressed which can lead to uncertainty and anxiety
  • Respectfully acknowledge feelings, without dismissing fears or concerns
  • People will be more likely to listen and respond if they believe their public officials are speaking knowledgeably and honestly
91
Q

8 Maintain consistent communication

A
  • Clear, timely, accurate, credible information
  • Empathetic, instructive and clear
  • Questions most also be answered consistently
92
Q

9 Work effectively with media

A
  • Establish clear communication channels
  • Establish a media list
  • Update media databases and contact information
  • Select those that reach large numbers of people
  • Separate facts from fiction by:
  • Making final reports, information and recommendations fully available
  • Openly and honestly relaying accurate information, including health and prevention messages based on scientifically valid data
  • Communicating health messages that are sensitive to cultural difference and community norms
93
Q

10 Wrapping up

A
  • Remain on the front lines to help people recover both physically and emotionally.
  • Reinforce important messages, promote risk avoidance and disease mitigation, and address any mishaps in the response efforts.
  • Meet with public officials and policymakers to review the crisis and
    establish policies that can help prevent similar disasters in the future.
94
Q

Antigen

A

A live or inactivated substance (e.g. polysaccharide or protein) capable of producing an immune response

95
Q

Antibody

A
  • Protein molecules (immunoglobulin) produced by B lymphocytes to help eliminate an antigen.
  • Antibodies are disease-specific. There are five classes of antibody – IgG, IgA, IgM, IgD and IgE, which have a range of functions.
  • They can act as ‘flags’ to direct the immune system to foreign material for destruction and form part of the innate/humoral immune response.
96
Q

Active immunity

A

Results when exposure to a disease organism triggers the immune system to
produce antibodies to that disease. Active immunity can be natural or artificial.
- Natural active immunity is acquired through infection with actual disease
- Artificial active immunity is acquired through vaccination
Immune person’s immune system recognizes the disease and immediately
produce the antibodies when exposed. Active immunity takes time (usually weeks) to develop but immunity is long lasting (sometimes life-long).

97
Q

Passive immunity

A

Results when a person is given antibodies to a disease produced externally other than own immune system. Passive immunity provides immediate protection, but short lasting (few weeks or months).

98
Q

Vaccine

A

A vaccine is a biological product that can be used to safely induce an immune response that confers protection against infection and/or disease on subsequent exposure to a pathogen. The vaccine must contain antigens that are either derived from the pathogen or produced synthetically to represent components of the pathogen. The essential component of most vaccines is one or more protein antigens or polysaccharide.

99
Q

Immunisation

A

A process by which a person becomes protected against a disease through vaccination. This term is often used interchangeably with vaccination or inoculation

100
Q

Types of vaccines

A
  1. a live organism that has been attenuated (i.e., weakened)
  2. an inactivated form that is either whole or fractionated (e.g., protein or polysaccharide component).
  3. recombinant vaccines, is made by genetic manipulation of the organism’s genomic material, and can be either live or inactivated.
101
Q

Virus vaccine

A

Use the virus itself, in a weakened or inactivated form. Many existing vaccines are made in this way, such as those against measles and polio. They require extensive safety testing
(image in OneNote)

102
Q

Viral-vector vaccines

A
  • A viral vector vaccine is made when genetic material from a virus is inserted into a unrelated, harmless virus.
  • When the viral vector gets into cells, it delivers genetic material that gives cells instructions for how to make the spike protein found on the surface of the COVID-19 virus.
  • Once cells displace the spike proteins on their surfaces, immune system creates antibodies that can fight the COVID-19 virus.
    (image in OneNote)
103
Q

Nucleic-acid vaccines

A
  • Use genetic instructions (in the form of DNA or RNA) for a coronavirus protein that prompts an immune response.
  • The nucleic acid is inserted into human cells, which then churn out copies of the virus protein; most of these vaccines encode the virus’s spike protein.
    (image in OneNote)
104
Q

Protein-based vaccines

A
  • Protein subunit vaccines include only the parts of a virus (harmless S proteins) that best stimulate immune system.
  • Once your immune system recognizes the proteins, it creates antibodies and defensive white blood cells to fight future invation.
  • Fragments of proteins or protein shells that mimic the coronavirus’s outer coat can also be used.
  • Nuvaxovid (Novavax) is a protein based COVID-19 vaccine
    (image in OneNote)
105
Q

Viral load

A

Amount of virus (such as HIV) present in the bloodstream. For the case of HIV, this is when it is most transmissible

106
Q

Undetectable viral load (U=U)

A

The amount of virus in their bloodstream is incredibly low. In the case of HIV, the concentration is so low that it can’t be passed on through sex. This can be achieved through medication. It is often denoted as U=U.

107
Q

Antimicrobials and Antibiotics

A

Antibiotics are medicines used to prevent and treat bacterial infections (more info in OneNote)

108
Q

Antimicrobial resistance (AMR)

A

Antimicrobial resistance (AMR) occurs when bacteria change in response to the use of these medicines. Organism not humans or animals, become resistant. These organisms may infect humans and animals. Emergence and spread of AMR has been usually attributed to the misuse or indiscriminate use of antibiotics as therapeutic drugs in human and animal health care or as antibiotic growth promoters (AGP) in the veterinary husbandry.

109
Q

National immunisation schedule

A

The Australian National Immunisation Program Schedule sets out the immunisations Australians are given at different stages in their life. The program aims to reduce the number of preventable disease cases in Australia by increasing national immunisation

110
Q

No Jab No Play

A
  • Federal policy: eligible for certain family support (Centrelink) payments, including childcare subsidies that range from 20–85% of total childcare costs
  • Came into effect in 2016
  • Existed prior but allowed for conscientious objection
  • Now only medical exemptions are allowed
111
Q

National Health Security Act

A

The National Health Security Act 2007 provides a national system of public health surveillance to enhance the capacity of the Commonwealth and the states and territories to identify, and respond to, public health events of national significance

112
Q

Biosecurity Act

A

The Biosecurity Act 2015 (Cth) gives the Commonwealth Minister for Health expansive powers to issue directions and set requirements (for up to 3 months) in order to combat a human biosecurity emergency
During the emergency period the Health Minister may:
* Issue any direction to any person (section 478) and determine any requirement (section 477) that the minister considers necessary to:

113
Q

Victorian state of emergency

A
  • Public Health and Wellbeing Act 2008: The Minister for Health may, on the advice of the Chief Health Officer and after consultation with Emergency (the Minister for Emergency Management and the Emergency Management Co-ordinator in Chief and the State Co-Ordinator), declare a state of emergency
  • Public Administration Act 2004: The Premier may declare that an emergency situation exists when satisfied that there is a serious risk to public health, an emergency exists which warrants the making of a declaration of a state of emergency, is necessary to assist all or part of the Victorian community to recover from an emergency
114
Q

Quarantine

A

Means of separating persons, animals, and goods that may have been exposed to a contagious disease
- Quarantine Act 1908 – repealed and replaced by the Biosecurity Act
- Offers more flexibility to respond to each incidence
In Victoria this was exhibited by numerous pandemic safety orders which revolved around isolation and quarantine

115
Q

Intentional (STD)

A

subjective desire to transmit the disease
- Accused must have, through their actions, sought to achieve infection of the victim
- Not enough that the accused knows they have the disease and engages in conduct aware there is a substantial, or even virtually certain, likelihood of transmission

116
Q

Reckless (STD)

A

wrongful disregard of a foreseen risk (e.g. accused aware of the possibility/probability their actions could result in transmission)

117
Q

Negligent (STD)

A

e.g. failed to get tested/notice symptoms

118
Q

Healthcare associated infection (HAI), aka: Nosocomial infections

A

Healthcare associated infections are defined as infections acquired in hospital, or occurring as a result of a procedure. Patients with HAI’s are ~3x more likely to die in hospital, stay longer and cost more. HAI’s are largely preventable

119
Q

The Swiss cheese model

A
  • A systems-based approach to risk management
  • Each slice = a layer of defence
  • Layers aren’t perfect!
    → Weaknesses exist
  • More layers reduce chance of errors
120
Q

Residential Aged Care Facilities (RACF)

A

Nosocomial infections acquired in Residential Aged Care Facilities (RACF simply means that an infectious disease was acquired in a RACF setting, it does not imply that it is preventable (very difficult to prevent). Occurs due to differences in medical procedures and prevention strategies

121
Q

Cohorting

A

Separation of individuals based on their disease profile
- Confirmed case
* Tested positive either with PCR or RAT
- Suspect case
* Close contact through resident contact, family contact or staff contact
- No identified infection risk
* No sign of disease and not a close contact

122
Q

Zoning

A

All RACF are broken into different sectors
Green
* No disease zones
* Test negative or recently cleared
Blue
* Areas between contaminated and non-contaminated zones
* “buffer zones”
* Could also be used as a suspect zone
Amber ( or gold)
* Quarantine zones
* Also used for suspected cases
Red (extra)
* Used for single room isolations if an amber zone is full or if it is not feasible to move the resident around

123
Q

Prisons

A

Another high risk setting (more info in OneNote)

Epidemiology (2 decks)

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