NURS 287 Final

• Non-specific body defences against infection (3)

  - anatomical and physiological barriers- interferons- inflammatory response
• Anatomical barriers and physiological barriers (4)

  skin, mucous membranes, macrophages, tears
• Interferons (2)


  - prevent binding of virus to uninfected cells- interferes with viral replication
• Inflammatory Response (3)

  - vascular- exudate- reparative
• Our immune system is a...

  specific disease
• The purpose of the immune system is to...

  respond to foreign proteins in the body and resist infection
• We can acquire immunity in two ways:

  active immunity and passive immunity
• Active Immunity (2)

  - Natural: antibodies are formed by the body in response to an antigen that we are infected with- Artificial: antigens (from vaccines) are given to stimulate natural antibody production
• Passive Immunity

  - Natural: antibodies are transferred from immune system of mother (placenta or colostrum)- Ariticifical: antibodies are injected from another source, such as an immunoglobulin
• Infection

  An imbalance between microorganisms and defences
• Infection begins with...

  colonization, where pathogens (bacteria, viruses) establish themselves in a host's body
• Local infection occurs when...


  pathogens remain confined to a specific area, causing symptoms like redness, swelling, and pain
• These symptoms occur when...

  the hosts' defence mechanisms are ineffective and the pathogen is causing tissue damage, hence the symptoms
• If infection spreads beyond the initial site...

  it becomes systemic, potentially affecting the entire body
• Septicemia


  a severe systemic infection when pathogens enter the bloodstream leading to a cascade of harmful effects
• The Chain of Infection (6)

  1. etiological agent2. reservoir3. portal of exit4. mode of transmission5. portal of entry6. susceptible host

  
• The Chain of Infection: Etiological Agent


  The microorganism responsible for causing the infection- Ex. bacterium, virus, fungus, or parasite
• The Chain of Infection: Reservoir


  Places where the etiological agent resides and multiple- Ex. humans, animals, or environmental sources like contaminated water or soil
• The Chain of Infection: Portal of Exit

  The route through which the pathogen leaves the reservoir- Common exits include respiratory secretions (coughing, sneezing), feces, urine, blood, and open wounds- Knowledge of these routes informs hygiene practices and isolation precautions
• The Chain of Infection: Mode of Transmission

  Transmission can occur through direct contact (touching an infected person or object - which is sometimes called vehicle transmission), indirect contact (contaminated surfaces), respiratory droplets, airborne particles, vector-borne (through insects or animals), or food/waterborne routes
• Understanding the mode of transmission aids in...

  implementing appropriate infection control measure
• Examples of Mode of Transmission (4)

  1. direct contact2. indirect contact3. droplet transmission4. airborne
• Mode of Transmission: Direct Contact

  Direct contact with reservoir (exchange of bodily fluids)- ex. biting, kissing, sexual transmission
• Mode of Transmission: Indirect Contact

  Indirect contact with reservoir (no exchange of bodily fluids)- ex. touching contaminated, inanimate objects
• Mode of Transmission: Droplet Transmission

  droplets of respiratory secretions- ex. sneezing, coughing
• Mode of Transmission: Airborne


  Procedures such as suctioning, i.e., aerosol-generating procedures
• The Chain of Infection: Portal of Entry

  - Once the pathogen is transmitted, it needs an entry point into a susceptible host- Entry can occur through mucus membranes (e.g. eyes, nose, mouth), open wounds, or invasive medical procedures
• The Chain of Infection: Susceptible Host


  An individual who lacks immunity or defense mechanisms against the pathogen
• Vulnerability can result from factors such as... (3)

  Age, underlying health conditions, or a weakened immune system
• Nursing Interventions

  Supporting the defences of a susceptible host
• RNs play a role in supporting the person through the following strategies (7):

  Hygiene, nutrition, fluids, reducing stress, blood glucose control, health promotion and education, immunizations/vaccines
• Epidemic (2)

  - Occurs when the new cases of a disease exceed the normal occurrence during a given period of time- an increase, often sudden, in the number of cases of a disease above what is normally expected in that population in that area
• Outbreak (2)

  - When a disease is more likely during a specific season and we see more than usual cases - Carries the same definition as epidemic but is often used for a more limited geographic area
• Endemic

  The constant presence and/or usual prevalence of a disease or infectious agent in a population within a geographic area
• Pandemic

  An epidemic that has spread over several countries or continents, usually affecting a large number of people
• An Epidemic May Result From... (5)

  1. A recent increase in amount or virulence of the agent2. The recent introduction of the agent into a setting where it has not been before3. An enhanced mode of transmission so that more susceptible persons are exposed4. A change in the susceptibility of the host response to the agent5. Factors that increase host exposure or involve introduction through new portals of entry

  
• Communicable Disease

  Illnesses caused by pathogenic microorganisms- Also known as infectious disease- Ex. influenza, TB, Zika virus, tetanus, COIVD-19
• Non-communicable Disease

  Diseases are not passed from person to person via chain of infection- Chronic diseases- Ex. cardiovascular, cancers, chronic respiratory conditions (asthma), diabetes
• Types of Infectious Agents (4)

  bacteria, viruses, fungi, parasites
• Management of Communicable Disease: Strategies (3)

  1. preventing infection2. limiting the spread of infections3. providing epidemiologic data