MPH Block 1 Flashcards
What is Charles Winslow’s definition of Public Health
Science and art of preventing Dz, prolonging life and promoting health and efficiency thru organized community effort
Epidemiology is based on what two fundamental assumptions?
Dz do not occur by chance
Dz are not distributed randomly in a population so indicates how/why dz process has occurred
What are the objectives of epidemiology?
ID etiology of dz and risk factors Determine extent of dz in community Natural hx and prognosis of dz Evaluate existing and new prev/therapy measures Provide foundation for policy
Epidemiology is a ___ focused science
Population
What happens to many …..?
What happens to one …..?
Many- focus of epidemiology on occurrence of health and dz in population
One- Population approach contrasts w/ clinical medicine’s primary concern w/ health and dz in the individual
Diseases are expressed biologically in ____ but ?
Individuals
No epidemiology study can be done on one person
Epidemiology studies humans in ______
Aggregate (groups)
Epidemiology conclusions as a population science are directly applicable to ?
Groups studied and only indirectly applicable to the groups studied
Top 10 achievements of Public Health (ELO)
Immunications Vehicle Safety Workspace safety Infectious Dz control Decrease CAD/CVA Safe/healthy foods Healthy mother/baby Family planning Fluoridation of water Tobacco as a hazard
In 1900 the top 3 causes of death were ?
Infectious Dzs: Pneumonia, Flu, TB, and GI infections
Diphtheria was #10
Infectious Dzs are ___ by nature
Volatile
What are the top risk factors for death today?
Heart Dz
Cancer
CVA
COPD
What are the top life style risk factors that risk death as of today?
Tobacco/ETOH Nutrition Obesity Inactivity Occupation/Environment exposure
What 4 parts of preventative medicine have been integral parts of military activities?
Clean
Field Hygiene / Sanitation
Force protection
Who is responsible for troop health?
CDRs
Legal and regulatory basis and rarely accomplished by medical channels alone
What part of the COC is the bridge between command and military medicine?
Special Staff Medicine
CDR and staff relationship
What DoD instruction directs all services to have programs and take action under the umbrella of Public Health/Force Health Protection?
DoDD 6200.04
Military PrevMed milestones include ?
Isolation wards US weather bureau- surveillance Vectors as Dz transmission mode Water sanitation- chlorination Sodium Hypochlorite Vaccines
What are the military PrevMed milestone distinguished persons?
James Tilton Joseph Lovell Walter Reed Carl Darnall Joseph Lyster
In prevention, what is the goal?
Preserve and promote health and well being
Prevention in public health moves interventions from ? to ?
Individual level to population level
What are the 3 levels of protection?
1: prevents onset of illness/injury prior to dz process beginning (imms)
2: measures leading to early Dx and prompt Dz treatment (screening- PAPs)
3*: reduction of morbidity and mortality from existing dz (events in medical treatment)
Define CPS as it’s mentioned in DHA-PI 6200.06
Services recommended by USPS/STF to prevent/reduce risk for HDz, cancer, infectious dzs, or other conditions that impact health
When was the USPSTF created?
1984
What is the USPSTF
US Prev Services Task force- independent volunteer panel of national experts/DoD reps
What is the purpose of the USPSTF?
Review scientific evidence regarding the effectiveness, risks and benefits of specific health care services
USPSTF assigns grade recommendations based upon what what 3 criteria?
Strength of evidence
Balance of benefits/harms
Doe NOT consider costs
USPSTF recommendations only apply to ?
Those w/out S/Sx of Dz in question
Services offered in PC setting
What does a USPSTF recommendation of no evidence mean?
Different from conclusion that service is ineffective
What do USPSTF grades mean?
A- substantial B- benefit is moderate C- can do it, considered on individual PT level D- don't do it I- idk, insufficient current evidence
What does the USPSTF recommend for primary prevention of CVD?
Statins
What is USPSTF’s recommendation regarding syphilis screening?
Asymptomatic non-pregnant adults and adolescent who are at an inc risk for syphilis infection
Define Communicable Dz
Microbes (bacteria, viruses, parasites and fungi) that spread, directly or indirectly, from one person to another
How does the natural history of dz begin?
Appropriate exposure (microbe) to/accumulation of factors to allow dz process to begin
Characteristics of the Apparent/Inapparent Infection Triangle
Apparent: Severe Dz, Mild Illness
Inapparent:
Preclinical: not clinically apparent but destined to be
Subclinical: infection w/out illness
Exposure w/out infection = no infection
Inapparent disease can include ? and ?
Latent: infection w/ no active multiplication of the agent
Carrier: PT harboring the organism but is not infected to the point of detection by serology (limited or chronic)
Define Infection
Entry and development/multiplication of an infectious agent in the body
Infection is not synonymous with ?
Inectious dz; result may be inapparent or manifest
Presence of living infectious agents on exterior/clothes does not prove ? but is a ?
Infection
Contamination
Define Latent/Latency Period
Time from infection to infectiousness
Define Incubation Period
Time interval between infection and onset of clinical illness/Sxs
Define Communicable Period
Period of time which an infectious agent may be transferred from carrier to new host
In many Dzs, the ? period is shorter than the ? period
Latent shorter than incubation
Incubation and Communicable periods of Measles
I: 14 days for rash
C: 4 days before to 4 days after rash
Incubation and Communicable periods of Hep A
I: 28-30 days
C: latter half of incubation to few days after onset of jaundice
Incubation and Communicable periods of Smallpox
I: 7-17 days
C: Onset of fever Sx to separation of scabs
Characteristics of the term of Quarantine
Individual: healthy
Duration: incubation
Location: home
Basis of Action: rare, police power
Characteristics of the term Isolation
Individual: sick
Duration: communicable period
Location: hospital
Basis of action: common standard precaution
What are the parts of the Epidemiologic Triad
What do they represent
Susceptible Host
Causative Agent
Environment
Factors that influence an infection
Human diseases result from the interaction of what four factors?
Susceptible Host
Causative Agent
Environment
Vector
What are the characteristics of the ‘Host’ part of the epidemiologic triad?
Age Prior exposure Susceptibility Co-Infection Immune response
What are the characteristics of the ‘Agent’ part of the epidemiologic triad?
Toxicity Virulence Infectivity Susceptibility to ABX Survival outside of body Reservoir
What are the characteristics of the ‘Environment’ part of the epidemiologic triad?
Climate
Physical structure
Population density
Social structure
Define Primary/Definitive Host
The organism that the pathogen reaches maturity and reproduces sexually in
Define Secondary/Intermediate Host
Organism that harbors the sexually immature parasite and is required for development and life cycle completion
Define Dead-End/Accidental Host
Organism that generally does not allow transmission to the definitive host
Define Natural Reservoir
Population of organisms/specific environment a infectious pathogen naturally lives and reproduces or is depended on for pathogens survival
A reservoir is usually ? and often ?
Living host of certain species that a pathogen survives
Often w/out causing Dz for reservoir itself
Define Human Reservoir
Humans infected by pathogens that exist on/in human body
How do carriers transmit the pathogen they’re infected with?
Transmit or develop Sx
Define Convalescent Carrier
Capable of spreading disease following a period of illness (common in hepatits and polio)
Define Asymptomatic Carrier
Never exhibit S/Sx of Dz but capable of infecting others (Salmonella Typhi)
What are the two modes of transmission?
Direct: contact, droplet
Indirect: airborne, vehicle borne (fomites), or vector borne (mechanical or biologic)
Give 3 examples of microbes transmitted through Direct Transmission
Herpes
Syphilis
Hookworm
Characteristics for Droplet Spread
Large drops (sneeze, cough, singing)
Short distance- less than 1m
Not suspended in air
Give 3 examples of microbes that transmit through droplet spread?
Pertussis
Meningococcal
Mumps
Define Indirect Transmission
Transfer of infectious agent from reservoir to host by suspended air particles/vehicles/vectors
Vehicle borne transmission includes ?
Give 3 examples of microbes that are transmitted through indirect transmission?
Food, Water, Fomites
Salmonella, HCV, MRSA
Vector Borne indirect transmission includes ?
What microbes are transmitted through this method?
Arthropods- mechanical, biological
Shigellosis/Bacillary dysentery, Plague (mechanical)
Malaria, Dengue (biological)
Define Airborne Transmission: Microbial Aerosols
Give two microbe examples
Aerosolized droplet nuclei
Small dust particles
Less than 5 um
Carried by air currents
TB, Measles
What form of transmission is a fly that’s carrying shigella from latrine to food?
Indirect vector borne, mechanical transmission
What form of transmission is staphylococcal poisoning from a single meal?
Indirect vehicle borne transmission, single exposure
What form of transmission is when a student sneezes on you in passing?
Direct transmission, droplet spread
What form of transmission is a cook with poor hand washing who contaminates salad?
Indirect vehicle borne transmission, probably multiple exposure
What form of transmission is a person with TB who repeatedly coughs during a 9hr flight?
Airborne transmission
What form of transmission is a child with impetigo that give you multiple hugs?
Direct transmission, person-to-person touch
Define Endemic
Define Sporadic
Habitual/constant presence of a disease within a geographic area
Occurs infrequently and irregularly
Define Epidemic
Occurrence in a community or region in excess of normal expectancy
Difference between an outbreak and a cluster?
Define Pandemic
O: more geographic limited
C: aggregation
Pan: worldwide epidemic
Define Ratio
Define Proportion
Quantitative relation between amounts
Type of ratio that relates a part to a whole
Define Rate
Measure of the frequency of an event occurring in a define population over a specific time
What is the rate formula?
First- determine frequency (# of cases, population size, period of calculation)
%=(# cases)/(population at risk) x 100
Define Morbidity Frequency Measures
Used to describe presence of Dz in population or probability of its occurrence
In Public Health Terms “disease” includes ?
Illness
Injury
Disability
Morbidity frequency measures includes what 5 characteristic rates?
Attack Incidence Secondary attack Point prevalence Period prevalence
Define Attack Rate
Number of people at risk when a disease develops /
Total # at risk
Time is NOT specified
Special type of incidence rate applied to narrow population observed for limited time, such as during an epidemic
Define Secondary Attack Rate
Susceptible people who have been exposed to primary case and serves as a good measure of person-to-person spread
Attack rate = ?
Incidence
Define Incidence
Number of new cases of Dz occur during specified time in population at risk of developing the disease
Measure of ‘risk’
What are the two parts of the Incidence rate?
Numerator- new cases of dz reported in a time interval
Denominator- average population at risk during time interval (only those who can become a numerator)
Incidence rate is sometimes uses the ?? of cases and is a ? so it must have ?
Absolute number
Rate
Element of time in denominator
Define Incidence Density
Number of new events per person-time (person months, person years)
Define Crude Rates
Data presented w/out any adjustment for any characteristics
