Community Exam 3

what is a cohort study?

group of persons (generally sharing some characteristic of interest) followed over a period of time to observe some health outcome

what are the three components of the epidemiologic triangle?

host, agent, environment

what is herd immunity?

immunity in most of a population → exposure unlikely

what is distribution in descriptive epidemiology?

patterns of events in populations: -what is the disease? -who is affected? -where are they? -when do the events occur?

what is morbidity rate?

ratio of the number of cases of a disease or condition to a given population

validity of a screening test is measured by...

sensitivity and specificity

what is epidemiology?

study of the occurrence and distribution of health-related states in human populations

what is pathogenicity?

the ability of an agent to *produce* *an* *infectious* *disease* in a susceptible host

who was john graunt?

was the first to look at and analyze birth/death reports (London, 1600s)

what is virulence?

*severity* of an infectious disease that results from exposure to the agent

what is indirect contact transmission? what is vectorborne transmission?

-AKA common vehicle; pathogen spreads to a host by nonliving objects (food, water, body fluids, clothing, toys) -vectorborne: pathogen spreads via insects (ex: mosquitos + malaria)

what is active immunity vs passive immunity?

-active: can be natural (actual infection with disease) or vaccine-induced (introduction of organism through vaccine) -passive: person is given antibodies (newborn antibodies through placenta/breastfeeding, antibody-containing blood products)

what are standard precautions?

-apply to all patients/clients in all settings -apply to blood, all body fluids, secretions, and excretions (except sweat) -also apply to non-intact skin and mucous membranes -includes hand washing and PPE (gloves, masks, eye protection, face shield, and gowns when risk for contact with blood/body fluids)

what environmental factors contribute to transmission?

-climate (temperature, rainfall) -plant and animal life (may be agents, reservoirs, or habitats for agents) -human population distribution (crowding, social support) -socioeconomic environment (education, resources, access to care) -working conditions (level of stress, noise, satisfaction)

what is a common source vs propagated source?

-common → everyone got sick from same source, happened at same time -propagated → I get sick from a source, and then spread it to another person; person to person spread

what are different methods/types of breaking the chain of transmission?

-control: to reduce the prevalence of disease (food and water control laws, spraying areas for insect control, immunizations) -isolation: mask, isolated rooms, etc. -quarantine: an enforced isolation or restriction of movement of those who have been exposed to an infectious agent during the incubation period -elimination: stopping transmission in geographic are -eradication: agent no longer present (worldwide)

what is an endemic, outbreak, epidemic, and pandemic?

-endemic: constant presence of a disease; baseline -outbreak: sudden rise in the incidence of a disease (ex: strep) -epidemic: widespread occurrence of a disease in a community at a particular time (can be diabetes, heart disease, overdose, RSV/flu in the winter) -pandemic: epidemic occurring worldwide or crossing boundaries

what is the web of causation model?

-expands on the epidemiologic triangle -reflects the complex interrelationships of numerous factors that interact to inc or dec a disease; there are many risk factors that contribute to disease vs. just a singular agent

what factors make someone a susceptible host?

-genetic susceptibility -immutable characteristics (ex: age) -acquired characteristics -current or preexisting disease (ex: immunological status, physiologic state) -lifestyle factors (ex: activity, diet, occupation)

how do we prevent hospital-acquired infections?

-hand washing -good nutrition and personal hygiene -prevention of UTIs (aseptic technique) -prevention of surgical wound infections (hand washing, surgical asepsis) -prevention of respiratory infections (clean nebulizers, turns on ventilators q 2 hours, suctioning, teeth brushing) -prevention of bacteremias: sterile technique with intravascular system

what factors influence emerging infectious diseases?

-human susceptibility to infection -travel, technology, industry -lack of political will and breakdown of public health infrastructure -climate, changing ecosystems, and human behavior -microbial adaptation and change (antigenic shifts and drifts)

what is zoonosis?

-infection transmitted under natural conditions from a vertebrate animal to a human -ex: West Nile virus, monkey pox, hantavirus, mad cow, rabies, parasitic diseases (malaria, guinea worm disease, etc.)

what are signs of infection?

-localized: inflammation, redness, warmth, swelling, pain, tenderness, loss of function; drainage; cellulitis -generalized: weakness, headache, malaise; fever, increased pulse, hypotension -elevated WBCs, c-reactive protein (marker for acute inflammation), sedimentation rate (marker for inflammation due to autoimmune disorder or infection)

what are rates in epidemiology?

-measure of the frequency of a health event or the number of cases in a defined population in a specified period of time; usually stated as a number of cases per 1,000 or 100,000 -include numerator (number of cases/episodes), denominator (total population at risk), factor (based on population; 100, 1000, 10,000, etc.), and time period (dates, weeks, months, years, etc.)

what is incidence rate and how is it calculated?

-number of NEW cases in a population in a specified period of time; affected only by factors related to risk of developing disease and not to survival or cure -calculation: (new cases at a specified period in time / total population at risk) x factor (100, 10,000, etc.)

how does implementation in the nursing process compare to implementation in the epidemiologic process?

-nursing: actions initiated to achieve goals -epidemiologic: actions initiated to implement plan

how does evaluation in the nursing process compare to evaluation in the epidemiologic process?

-nursing: goal achievement evaluated -epidemiologic: actions evaluated; further research conducted if necessary

how does diagnosis in the nursing process compare to diagnosis in the epidemiologic process?

-nursing: healthcare needs and assets identified; goals established -epidemiologic: hypothesis formulated, data analyzed to test hypothesis

how does assessment in the nursing process compare to assessment in the epidemiologic process?

-nursing: individual client database established; data interpreted -epidemiologic: data gathered from reliable sources; scope of the problem defined (person, place, and time)

how does planning in the nursing process compare to planning in the epidemiologic process?

-nursing: processes to achieve goals are selected -epidemiologic: plans made for control and prevention of condition

what are examples of agents?

-nutritive elements (excesses of cholesterol, deficiencies of vitamins, proteins, etc.) -infectious agents (bacteria, viruses, fungi, parasites) -chemical agents (poisons, allergens, heavy metals, toxic chemicals, pesticides) -physical agents (ionizing radiation, mechanical)

what are agents of bioterrorism?

-organisms or toxins that pose the highest risk to the public and national security -ex: anthrax, small pox, tularemia, plague -important to identify temporal or geographical clustering of illnesses, unusual age distribution for a common disease, or irregular illnesses

what is the natural history of disease model?

-outlines four stages of disease: susceptibility (pre-exposure), subclinical disease (preclinical), clinical disease, and resolution -the stage between exposure (subclinical) and the onset of disease (clinical) is the incubation period in infectious disease / latency period in chronic disease

what are characteristics in descriptive epidemiology?

-person: race, ethnicity, sex, gender, age, education, etc. -place: geography, location (does the rate of disease differ from place to place?) -time: is there an increase or decrease in the frequency of disease over time? → secular (long-term), point epidemic (pronounced cluster in short time frame), cyclical (seasonal, recurring), or event-related clusters (unusual aggregation)

what are the characteristics of each stage of the natural history of disease model?

-pre-exposure (susceptibility): factors present leading to problem development -pre-pathogenesis (preclinical, subclinical): exposure to causative agent (microorganism, carcinogen, or other disease-causing entity); pathologic changes occur -pathogenesis (clinical): disease present; onset of symptoms, usually receive diagnosis at beginning of this stage -resolution: problem resolved; recovery, disability, or death

when does primary, secondary, and tertiary prevention occur in the natural history of disease model?

-primary: pre-exposure and preclinical stage -secondary: clinical stage -tertiary: resolution stage

what is primary vs secondary vaccine failure?

-primary: vaccine didn't work for someone; didn't create immune response/build immunity -secondary: after time (5-7 years), immunity from vaccine wears off

what is attack rate? how is it calculated?

-proportion of persons exposed to an agent who also develop the disease -calculation (reported as a percentage): (number of cases of the disease / total population exposed) x 100

what is the difference between prospective cohort studies and retrospective cohort studies?

-prospective (longitudinal): subjects are free of the outcome under investigation; they are followed over time and data about them is collected as their characteristics or circumstances change -retrospective (historical): members are classified according to exposure status at some time in the past (may be conducted using only past records)

what is the best evidence gathering in EBP?

-randomized control trial (RCT) -random assignment to groups (participants do not know which group they're in); experimental group receives treatment -gold standard for collecting evidence

what is mortality rate? what is crude mortality rate versus cause-specific mortality rate?

-ratio of the number of deaths in various categories to a given population -crude: number of people who have died from all causes during a certain time period; divided by total population -cause-specific: number of deaths from a specific cause; divided by total population

what is direct contact transmission? what are examples? what are the transmission-based precautions?

-requires close association between infected and susceptible host (ex: physical skin-to-skin contact, sexual contact) -examples: MRSA, C. diff, norovirus -precautions: private room, clean/non-sterile gloves, gown

what is droplet transmission? what are examples? what are the transmission-based precautions?

-respiratory droplets propelled short distance when someone talks, coughs, or sneezes → contaminate surfaces or enter the mucosa of another person (direct or indirect contact) -examples: pneumonia, meningitis, rubella, mumps, pertussis, COVID-19 -precautions: private room (door can be open), surgical mask, gown and gloves (contact component)

what is airborne transmission? what are examples? what are the transmission-based precautions?

-small particles are suspended in the air from coughing/sneezing → breathing in causes infection -examples: measles, TB, varicella, shingles -precautions: private room with monitored negative air pressure (door closed), N95 mask

what is the epidemiologic triangle model?

-states that disease results from the interaction between an *agent* and the *susceptible* *host* in an *environment* that supports transmission

what is social epidemiology?

-studies the social distribution and social determinants of health and disease -focus on the roles and mechanisms of specific social phenomena -examines social inequalities and data related to neighborhoods, communities, employment, and family conditions to analyze health issues + to design appropriate/feasible public health interventions

what is analytic epidemiology?

-study of the determinants of the patterns/outcomes observed -the *how* and *why* ; the factors that influence observed patterns of health and disease + increase the risk of adverse outcomes

what is descriptive epidemiology?

-study of the distribution of disease, death, or other health outcomes in the population according to person, place, and time; provide a picture of how things are or have been -the *who*, *where*, and *when* of disease patterns

what are the definitions of study, occurrence, distribution, determinants, and control?

-study: research and how we learn about disease states -occurrence and distribution: indicate who contracts acute or chronic illness or injury and where they are occurring -determinants: risk factors for contracting illnesses or injuries; include age, sex, genetics, or social influences (education, income, insurance) -control: refers to primary, secondary, and tertiary efforts to prevent or lessen negative effects of illness/injury or maximize wellness

what is risk in epidemiology? what are risk factors? populations at risk?

-the likelihood or probability that a particular condition will occur within a specified period of time -risk factor: factor that increases the probability that a health event may occur (ex: cigarette smoke, excessive stress) -population at risk: groups or people who have a greater potential for developing a particular health problem (ex: men at risk for breast cancer but not for ovarian cancer)

what is prevalence rate and how is it calculated?

-the number of ALL cases of a specific disease at a given point in time (new and old cases); measures existing cases of disease and is affected by factors that influence both the risk (incidence) and survival/recovery (duration) -calculation: (existing cases at a specified period in time / total population at risk) x factor (100, 10,000, etc.)

what is reliability of a test?

-the precision/reliability of what the test is measuring -its consistency or repeatability; every time you take this test, is the result the same every time?

what is relative risk and how is it calculated?

-the risk of an event relative to exposure; the probability of an event occurring in the exposed group versus the non-exposed group -usually reported as ____ times more likely -calculation: risk of number exposed divided by risk of people not exposed -example: 1 in 10 people to cigarette smoke get cancer (risk =0.1); 1 in 100 people not exposed get cancer (risk = 0.01); 0.1 / 0.01 = 10; smokers are 10x more likely to get cancer

what are neutropenic precautions?

-used to prevent infection among clients with immunosuppression -assess skin integrity q 8 hours, respiratory assessment and temp every 4 hours -monitor CBC and differential daily -no one sick in the room -no fresh flowers -clean room daily -excellent hand hygiene, good body hygiene, excellent IV care -no fresh unpeeled fruits and vegetables

what is vertical transmission vs. horizontal transmission?

-vertical: passing of an infection from parent to off spring (breast milk, intra-utero, through birth canal, etc.) -horizontal: person-to-person spread of infection

what education would you provide to to avoid waterborne and foodborne illnesses?

-washing hands and surfaces often -preventing cross-contamination -cook to the right temperature -refrigerate promptly -preventing recreational waterborne illnesses (staying out if you have diarrhea, don't swallow water, shower before/after, change diapers in changing rooms and wash hands) -routine samples from public water sources/private well water

what is the nurse's role in investigating an outbreak?

1. Establish the existence of the outbreak. 2. Describe the outbreak according to person, place, and time. 3. Formulate and test hypotheses as to the most probable causative factors. 4. Implement a plan for control of the outbreak and prevention of further outbreaks. 5. Evaluate results, prepare reports, and conduct further research if necessary.

In a long-term care facility of 366 patients, 27 were newly diagnosed with healthcare-associated pneumonia. 1. Incidence or prevalence? 2. What is the incidence per 100?

1. incidence (only talking about new cases) 2. 27 / 366 x 100 = 7.4 per 100 people

what are the phases of disease development?

1. latency: replication before shedding (hasn't infected person yet, cannot infect others) 2. incubation period: the interval between invasion by an infectious agent where there are no symptoms or the first appearance of signs and symptoms 3. communicable period: the interval during which an infectious agent may be transferred

What is the mortality rate of men that died from diabetes if 100 men died out of 900 men? (x100)

100/900 x 100 = 11 → 11 deaths per 100 men

A nurse is preparing a community health program on communicable diseases. When discussion modes of transmission, the nurse should include which of the following illnesses as droplet? •A. Cholera •B. Malaria •C. Influenza •D. Salmonellosis

C. Influenza

You are caring for a patient with HIV in the hospital. To best care for this patient and perform proper infection control measures, you should do all of the following except: A. Wash hands and other parts of the body immediately after contact with blood or other body fluids B. Wear gloves at all times when in this patient's room C. Use and dispose of needles and other sharp instruments appropriately.

B. Wear gloves at all times when in this patient's room

Between January 1 and December 31, 35 new cases of tuberculosis were diagnosed in a city. There were a total of 300 active cases among the population of 400,000 on December 31 of that year. Twenty deaths from tuberculosis were recorded during the 1-year period. What is the cause-specific death rate per 100,000 for tuberculosis during the year? A. 75 B. 0.005 C. 5 D. 0.075

C. 5 20/400,000 x 100000

Between January 1 and December 31, 35 new cases of tuberculosis were diagnosed in a city. There were a total of 300 active cases among the population of 400,000 on December 31 of that year. Twenty deaths from tuberculosis were recorded during the 1-year period. What was the prevalence rate of tuberculosis per 100,000 on December 31? A. 0.00075 B. 0.10 C. 75 D. 8.75

C. 75 300/400,000 x 100000

The new cases of TB were all assigned public health clinics to receive Direct Observation Therapy (DOT) for administration of TB medications. What level of prevention is this? A. Primary B. Secondary C. Tertiary

C. Tertiary

A nurse is preparing an education program on disease transmission for employees at a local day care facility. When discussing the epidemiological triangle, the nurse should include which of the following factors as an agent? A. Altered immunity B. Resource availability C. Toxin D. Ethnicity

C. Toxin

what is an emerging infectious disease?

a newly identified, clinically distinct infectious disease or the reappearance (or reemergence) of a known infectious disease after its decline in a certain geographic area or population

what is a proportion in epidemiology?

a type of ratio in which the denominator includes the numerator (part of the whole) -example: 14,000 new HIV infections a day around the world; 13,300/14,000 occur in people who live in low and middle income countries (.95, 95%)

what is specificity?

ability of a test to detect true negatives; indicates people who do not have the disease

what is sensitivity?

ability of a test to detect true positives; indicates people who have disease

what is invasiveness?

ability of an agent to *destroy* *body* *cells*

what is infectivity?

ability of an agent to *invade* a host and replicate

what is immunogenicity?

ability of an agent to *produce* *specific* *immunity* within the host

what is toxicity?

ability of an agent to produce *toxins*

what is evidence based practice?

an approach to providing the highest quality of heath care in all settings to improve health outcomes

what is colonization?

an infectious agent is present, but there is no sign of disease (ex: MRSA being on the skin/mucous membranes, but no infection being present)

who can be attributed to modern epidemiology?

began in 19th century -John Snow (1854): researched transmission of cholera in London; found that death rates were higher in one area and removed water pump handle to reduce the spread -Louis Pasteur (1860s-80s); developed pasteurization to remove "germs" that caused disease

Between January 1 and December 31, 35 new cases of tuberculosis were diagnosed in a city. There were a total of 300 active cases among the population of 400,000 on December 31 of that year. Twenty deaths from tuberculosis were recorded during the 1-year period. What was the incidence rate per 100,000 people for tuberculosis during the year? •A. 75 •B. 0.875 •C. 0.0006 •D. 8.75

•D. 8.75

What stage of the natural history of disease does tertiary prevention fall under? •A. pre-exposure •B. pre-clinical •C. clinical •D. resolution

•D. resolution