FCP Flashcards
Public Health Definition
Art of Preventing Disease
Prolonging Life
Promoting Health
4 Aspects of Public Health Approach
Surveillance
Risk Factor Identification
Intervention Evaluation
Implementation
What are the 10 Public Health Essential Services?
Monitor Health of Community Diagnose Educate Mobilize Partnerships Develop Policies Enforce Laws Link People to HS Competent Workforce Evaluate Quality of HS Research
Determinants of Health of Population
Social Characteristics
Genes / Biology
Health Behaviors
Medical Care
Community Diagnosis
Identification / Quantification of Health Problems in Community
Clinical vs Community Diagnosis
Clinical (History / Exam / Test / Diagnosis)
Community (Talk / Records / Survey / C. Diagnosis)
Aim of Community Diagnosis
Prevention & Promotion
What is Occupational Health
Promotion + Maintenance of Physical / Mental / Social Well Being of Workers
What are the 4 Objectives of Occupational Health
Maintenance + Promotion of Workers Health
Prevent Diseases
Protect Workers
Safe Workplace Environment
Difference Between Occupational Disease & Work Related Disease?
Occupational - Cause Specific (Silica in Factory)
Work Related - Multifactorial (Work Stress)
Hazard
Ability of Agent to cause damage to biologic material
Exposure
contact to hazard that allows effective transmission
Risk
Probability that adverse effects will occur
Workplace Assessment (3)
Workplace Risk Evaluation
Risk Communication
Risk Management
How is Workplace Risk Evaluation carried out? (4 Steps)
Hazard Identification
Hazard Evaluation
Exposure Assessment
Risk Characterization
Risk Communication
Using Info Gathered this is the follow where the responsible personnel makes informed and independent decisions about Health / Safety Risks
When risk communication is conducted prior to exposure this is called?
Primary Prevention
Risk Management
Employer / Employee / Medical Consultant manage risk
What are the 4 options in Risk Management?
Exposure Reduction / Elimination
(PPE not primary mode this is the most desirable)
Temporary Job Transfer
(High risk and reduction / elimination not possible)
Disability Leave
(Exposure wont be reduced & transfer not possible)
Remove Individual from Work
(Last Desirable)
What are the 6 environmental (Engineering) measures taken ?
Substitution Isolation (Other workers not affected) Segregation (Away from workplace) Ventilation Environmental Monitoring Ergonomics
What are the 3 medical / personal measures taken?
Pre Employment Medical Examination
Periodic Medical Examination
Biologic Monitoring
What is the aim of Pre Employment Examination (PEE) ?
Baseline Medical Data (Medicolegal)
Identify Highly Susceptible Individuals and advise regarding suitability of work and his health
What is the aim of Periodic Medical Examination (PME) (4 Aims) ?
Early Disease Detection (Better Treatment / Prognosis)
Early Removal of Susceptible Individuals (Prevention)
Early Detection of Hazardous Jobs
(To apply Engineering / Control Measures)
Evaluation of Previous Prevention / Control
What does Periodic Medical Examination include?
Questionnaire
Screening tests
Periodic Audiometry
Periodic CXR / Ventilatory Function
What is Biological Monitoring?
Part of Periodic Medical Examination
Measuring Elements / Metabolites in biological fluids
Aim of PPE
Prevent penetration of uncontrolled hazardous exposure
Organized and Systematic way of finding answers to questions
Research
Types of Health Research
Quantitative (Numerical)
Qualitative (Non Numerical)
Mixed Methods
PICO Approach
Population
Intervention
Comparisons
Outcomes
4 Ws Format
Who
What
Where
When
Different types of epidemiological studies?
Descriptive (No Comparison)
Analytical (Comparison)
Types of Descriptive studies
Case Report
Case Series
Ecological Studies
Types of Analytical Studies
Observational
(Cohort / Case Control / Cross Sectional)
Interventional
(Clinical Trial / Community Trial)
Case Report
Clinical Phenomenon in Single Patient
Case Series
More than one patient with similar problems
Limitations of Case Report / Case Series
External Validity
Confounding
Ecological Studies
Average Exposure - Frequency of Disease in Populations
Ecological Fallacy
Conclusions on individuals based on analyses of group data
(high income is
associated with high mortality from cancer at the
individual level. In fact at individual level we may
observe the reverse: mortality from malignancy is
lower with high income)
Cross Sectional
Exposure and Disease at one Point (snapshot)
Cohort
Exposure + Look Forwards to outcome (Prospective)
Case Control
Identify disease status then look backwards to exposure (restrospective
Which study is known as prevalence study?
Cross Section
Advantages of Cross Section
Simple
Cheap
Quick
Gives Prevalence
Disadvantages of Cross Section
Not for Rare / Short Duration Diseases
May result in wrong conclusion
No Solid Evidence
Types of Cohort Studies
Prospective
Retrospective
Reconstructive
Relative Risk
Incidence in Exposed / Incidence in unexposed
Attributable Risk
Incidence in Exposed - Incidence in Unexposed
Relative Risk Interpretation
=1 Risk Same
>1 Increased Risk (Exposed)
<1 Decreased Risk (Exposed)
Confounding
Measure of association or effect between exposure and outcome is distorted by the presence of another variable.
How to Deal with Confounding Factors (Design Stage)
Restriction
(Admission of those free from confounder)
Randomization
(Distribute the confounders equally)
Matching
(Distribution of confounders in different groups)
How to deal with confounding (Analysis Stage)
Stratification (Analyzing at different levels)
Modeling (Using regression techniques)
Advantage of Cohort Studies
Incidence Rate Calculation
Estimates of RR / AR
No Recall Bias
Suitable for Rare Exposure
Disadvantages of Cohort
Large Number of People Long time Not for rare diseases / low incidence Loss to follow up Expensive Loss of staff People behavior changes Ethical Problems
Which type of study is Cohort Study
Observational
Analytical
Disease caused by transmission of pathogenic agent to host
Communicable Disease
Progression of disease in absence of treatment
Natural History
Spectrum of Disease
Manifestations present in each infected individual
Epidemiological triad
Agent
Host
Environment
Infectivity Ratio
Number Infected / Number Exposed
Basic Reproduction Number RO
Number of secondary infections that result from primary infection in SUSCEPTIBLE population (R is number in both susceptible and unsusceptable)
Interpret R0 Number
Example R0 for Measles is 15
Each new case of measles 15 new secondary cases
What is the R0 Number in an epidemic?
Must be >1
Effective Reproductive Number (R)
Average number of secondary cases per infectious case in a population made up of both
susceptible and non-susceptible hosts.
Effective Reproductive Number (R) Interpretation
> 1 - Number of cases will increase
=1 - Endemic
<1 - Decline in number of cases
Pathogenicity
Extent to which clinically manifest disease is produced in infected population
Pathogenicity Ratio
Number developing clinical illness / Number infected
Virulence
Extent to which severe disease is produced in population
Virulence - Very Severe
Virulence Ratio
Number with severe disease / Number with disease
Infective dose of infectious agent
Number of organisms needed to cause infection
Resevior
Place where infectious agent can live and multiply
Preclinical disease
Disease not clinically apparent but destined to progress to one
Sub-Clinical
Not clinically apparent and not destined to become apparent
Latent Infection
No active multiplication
Modes of Transmission
Direct (Same Place)
Indirect (Vehicle / Vector)
Airborne (Droplet / Dust)
Vertical modes of transmission
In Utero (Pregnancy)
Perinatal (During Delivery)
Breast Feeding
Incubation Period
Time between invasion and first sign / symptom
Period of Communicability
time where agent may be transferred from person to person
Ability of agent to cause clinical manifestations
Antigenicity
An individual who is neither immune or infected
Susceptible individual
Permanent reduction of Disease worldwide to zero with no agent detected in environment
Eradication
Reduction of infection / disease to zero with agent present
Elimination
Eradication vs Elimination
Eradication - Agent isn’t in environment
Elimination - Agent present in environment
Examples of Eliminated diseases
Measles
Polio
(Aka reduced but agent present)
Example or Eradicated Disease
Small Pox
Level of Prevention
Primary - Prevention of Disease
Secondary - Early Detection
Tertiary - Prevent Deterioration
(PED)
Primary Prevention
Reduce incidence of Disease / Risk Factor
Secondary Prevention
Reduce prevalence by shortening duration of infection
Tertiary Prevention
Reduce / Eliminate Long Term Impairments
Control Measures of Cases (7)
Case Finding Notification Isolation Disinfection Treatment Release Others (Follow Up)
Control Measures of Contacts (5)
Enlistment Examination Stop Exposure Surveillance Segregation Specific Protection
Permanent incidence reduction to Zero (Worldwide)
Eradication
Reduction to zero (Defined area)
Elimination
Reduction to locally accepted level
Control
Agent no longer exists in nature or lab
Extinction
Virulence
Cause Serious Disease
Pathogenicity
Cause Disease
Infectiousness
Transmission
Infectivity
Ability to infect
Control Measures applied to infectious agents
Cleaning Cooling Pasteurization Disinfection Sterilization
Control Measures applied to host
Vaccination Prophylaxis Behavior Barrier Improving Host Resistance
Control Measures applied to environment
Safe Water Provision
Feces Disposal
Food / Milk Sanitation
Types of Observational Studies
Cross Sectional
Cohort
Case - Control
(No Intervention)
Case Control Study
Cases identified and compared with individuals without condition of interest (Controls)
When is a Case Control Study Desirable
Rare Disease
Dynamic Population
Little Known about RF
Optimum Selection of Controls
Multiple Control Groups (Different Sources)
Matching (Similar to cases)
Size (Equal to Case Group)
Types of Bias
Interviewer (Use Objective Method) Recall Selection Measurement Observer Bias
Odds Ratio
Odds of Exposure in Cases / Odds of Exposure in Controls
Or
AD/BC
Advantages of Case Control
Easy Cheap Rare Diseases No Risk Study of Several Factors No loss to follow up No Ethical Problems
Disadvantages of Case Control
Bias
Validation of Info
Appropriate Control Selection difficult
Odds Ratio is an estimate of RR with low prevalence diseases only
Which study is more Suitable for Rare Diseases
Case Control
How to remove bias in Clinical Trials?
Randomization
Blinding
Levels of Blinding
Individual
Investigator
Analyst
Key Elements of Clinical Trial
Selection Randomization Blinding Data Collection Statistical Issues Ethical Considerations
Inert compound given to subjects in clinical trial
Placebo
Types of RCT endpoints
Primary (ex. Cured 3+ Months)
Surrogate
Composite (Death / Attack)
Safety
Rules to stop trial
Severe Side Effects
Benefit becomes undeniable
Statistical Issues that can arise
Sample Size
Analysis
Intent to treat Analysis
All participants enrolled in trial (Completed the trial or not)
Per Protocol Analysis
Only who completed trial
Number Needed to Treat Formula
1 / (Incidence control - Incidence Treated)
or
1 / Absolute Risk Reduction
Efficacy Formula
(Incidence placebo - Incidence Treatment) / Incidence Placebo
Inactivated Toxins
Diphtheria and Tetanus
Inactivated Complex Antigens
Whole-cell pertussis
Purified Antigen
Acellular Pertussis
Recombinant Antigens
Hepatitis B Recombinant Vaccine
Live Attenuated
Measles
Under Which Condition does WHO grant certification of elimination?
Interruption of Transmission lasted at least 3 consecutive years
Transmission of disease no longer active in certain area
Elimination
Which diseases have been eradicated ?
Smallpox
Rinderpest
Causative Agent of Tetanus
Clostridium Tetani
Tetanus is which type of Bacteria
Anaerobic
Motile
Gram +
Main Reservoir of Tetanus
Soil
Names of Tetanus Toxins
Tetanospasmin
Tetanolysin
Which neurotoxin causes clinical manifestations of Tetanus
Tetanospasmin
When does tetanus produce toxins
Low Oxygen Levels
Spore - Germinates - Active Vegetative State - Multiplies - Produces Toxin
Mode of Transmission of Tetanus
Percutaneous (Must pass skin barrier)
No Wound - No Tetanus
Lethal dose of tetanus
0.1 Mg for 70 Kg Man
Incubation Period of Tetanus
3 - 21 Days
Types of Tetanus
Traumatic Puerperal Otogenic Idiopathic Neonatorum Cephalic
What can prevent tetanus
Immunization
When is the combined tetanus diptheria pertussis vaccine offered?
Months 2 / 4 / 6
Booster ( 18th Month / 5 Years / 10 Years / 16 Years)
When is the monovalent vaccine offered?
0 / 2 / 12 Months
Booster after 5 then every 10
When is TdaP given to adults
Every 10 Years
How long does the tetanus Ig produce protective antibody levels for?
4-6 Weeks Atleast
Tetanus Vaccination in Children
Months 2 / 4 / 6 / 18 (Booster)
4th Year Primary
After 10 Years 3rd Dose
Tetanus prevention in Pregnancy (Not Previously Immunized)
First Dose - 6th Month
Second Dose - After 1 Month until 2 Weeks Before Delivery
Third Dose - After 6-12 Months or Next Pregnancy
Fourth/Fifth - After one Year
Tetanus Prevention in Pregnancy (Immunized)
Two Doses - After First Trimester till 2 Weeks Before Delivery
Third Dose - After 6/12 Months or Next Pregnancy
Tetanus vaccine in adults (Immunized)
Booster every 10 Years
Tetanus Vaccine in soldiers / farmers / gardeners
Two doses one month apart
Third Dose after 6 - 12 Months
Tetanus Case Management
Medical Emergency - Hospitalization Patent Airway TIG Immediately Wound Care Antibiotics
Does tetanus disease give immunity?
No
Tetanus contacts management
Nothing
Which type of Virus is Rabies
Non-segmented
Negative Stranded
RNA
(Rhaboviridae Family)
Rabies transmission
Direct Contact
Through Mucus Membranes
Most effective strategy for preventing Rabies
Vaccinating Dogs
Types of Rabies Vaccines
Human Diploid Cell Vaccine
Rabies Vaccine Adsorbed
(5*1ml Doses deltoid region)
Mechanism of Action in Rabies
Multiplication in Nervous tissue
Polio Incubation Period
14 Days
Polio Mode of Transmission
Direct Droplet
Faeco-Oral Infection
Types of Polio
Non-Paralytic
Paralytic
Non Paralytic Polio
Stiff / Pain Neck
2-10 Days
Rapid Recovery
Paralytic
Paralysis in 4 days
IPV Vaccination
2 / 4 / 6 /18 Months
4-6 Years
OPV Vaccination
2 / 4 / 6 / 9 / 12 / 18 Months
Which polio vaccine Builds mucosal immunity?
OPV (Oral)
FINER Acronym Research
Feasible Interesting Novel (New Findings) Ethical Relevant
PICO
Population
Intervention
Comparison (Type of Control)
Outcome
Emerging Infectious Disease
Newly discovered infectious agent
Re-emerging Infectious Disease
Previously controlled but risen again to be a problem
What are factors affecting emerging / reemerging diseases
Ecological Changes Human Demographics International Travel Microbial Adaptation Breakdown Intent to Harm War
How do ecological changes affect emerging / remerging diseases?
Global warming increases temperature
Increase in waterborne / vector transmission
Epidemic
Disease that affects large number of People within community / population / region
Pandemic
Epidemic that spread over multiple countries or continents
Endemic
Constant presence in a specific location
How many phases is the WHO Pandemic Alert system?
6 Phases
Phase 1 WHO PS
Virus in animals
No infections in humans
Phase 2 WHO PS
Animal Virus
Caused Infection in humans
Phase 3 WHO PS
Clusters of disease in humans
No Outbreaks
Phase 4 WHO PS
Spreading from person to person
Outbreaks at community level
Phase 5 WHO PS
More than one country
Same Region
Phase 6
More than one country
Different region
Phases Recap
1 - No infection 2- Human Infection 3 - Cluster of infection 4 - Community Outbreak 5 - More than one country 6 - Country in a different region
Types of Epidemic Curves
Point Source
Continuous
Propagated
Point Source Outbreak
Common contaminated source
Describe the point source epidemic curve?
Rapid increase with slower decline
All Cases one incubation period
Describe the continuous common source curve
Rise to a peak then falls
Not in a single incubation period
Example of Common Source
Cholera
Example of Point Source
Hepatitis A
Example of Point Source
Hepatitis A
Propagated epidemic example
Measles
Propagated curve description
Series of successively large peaks
One Incubation period apart
Measures to prevent emerging infectious disease
Surveillance
Applied Research
Infrastructure / Training
Prevention / Control
Nuremberg Code
Informed consent is essential
Declaration of Helsinki
Protocol should be submitted for ethical review
Ethical Requirements of Research
Validity Social Value Community Partnership Favorable Risk/Benefit Fair Subject Informed Consent Independent Review
Levels of IRB Review
Full Board - More than minimal Risk
Expedited - Minimal Risk
Exempt - Observational Only