Fundamentals Chap 28 Flashcards
What is a pathogen?
- Infectious agent
* Presence does not mean an infection will occur
What is colonization?
*Organism that multiplies w/in a host but does not cause an infection
What is an infectious disease?
- illness such as viral meningitis or pneumonia
- have a low to no risk for transmission
- can be serious for pt
What is a communicable disease?
*an infectious disease that is transmitted directly from one person to another
What is pH?
*acidity of the environment
What is the portal of exit?
*sites such as blood, mucus membranes, respiratory tract, genitourinary tract, and gastrointestinal tract
What is the major route for transmission?
*unwashed hands of a health care worker
What is virulence?
*ability to survive in the host or outside the body
What is susceptibility?
*individual’s degree of resistance to pathogens
What is immunocompromised?
*having an impaired immune system
What is a reservoir?
*a place where a pathogen survives
Who are carriers?
*persons who show no symptoms of illness but who have the pathogens that are transferred to others
Development of an infection occurs in a cycle that depends on what agents?
- infectious agent or pathogens
- reservoirs or source for pathogen growth
- port of exit from reservoir
- mode of transmission
- port of entry to a host
- susceptible host
What are the most common modes of transmission?
- direct
- indirect
- airborne
- droplet
- vehicle
- vector
What is bactericidal?
*a temperature or chemical that destroys bacteria
How is infection transferred by direct means?
*person to person (feces, oral) physical contact between source and susceptible host (touching pt feces and then touching your inner mouth or consuming contaminated food)
How does indirect mode of transmission occur?
*personal contact of susceptible host w/ contaminated inanimate object(Needles or sharp objects, dressings, environment)
How does droplet mode of transmission occur?
*large particles that travel up to 3 feet during coughing, sneezing, or talking and come in contact w/ susceptible host
What are the vehicles for modes of transmission?
- contaminated items
- water
- drugs, solutions
- blood
- food (improperly handled, stored, or cooked; fresh or thawed)
How does airborne mode of transmission occur?
*droplet nuclei or residue or evaporated droplets suspended in air during coughing, sneezing, or carried on dust particles
What is localized infection?
- a wound infection
- pt usually experiences localized symptoms such as pain, tenderness, and redness at wound site
- use standard precautions (ppe, hand hygiene)
What are the vectors of the mode of transmission?
external mechanical transfer (flies)internal transmission such as parasitic conditions between vector and host *mosquito, louse, ticks, fleas
What are the normal body defenses against infections?
- normal flora
- body systems defenses
- inflammation
How does the normal flora work?
- they general don’t cause harm when where they are suppose to be
- maintain a sensitive balance w/ other microorganism to prevent infection
What is systemic infections?
*an infection that affects the entire body instead of just a single organ or part and can become fatal if undected and untreated
How does inflammation work against infections?
- protective vascular reaction that delivers fluid, blood products, and nutrients to an area of injury
- cellular response of the body to injury, infection, or irritation
How does the body defenses work against infections?
*each organ system has defense mechanisms physiologically suited to its specific structure and function
How does vascular and cellular response work?
- rapid vasodilation occurs, allowing more blood near the location of the injury
- increase in local blood flow causes the redness and localized warmth at the site of inflammation
What is inflammatory exudate?
- accumulation of fluid and dead tissue cells and WBCs form at site of inflammation
- may be serous, sanguineous, or purulent
- usually cleared away by lymphatic drainage
What is acute inflammation?
*immediate response to cellular injury
What is exogenous?
- comes from microorganisms found outside the individual such as Salmonella, Clostriduim tetani, and Aspergillus
- they do NOT exist as normal floras
What are Health care-associated infections (HAIs), also called nosocomial?
- occur as the result of invasive procedures, antibiotic administration, the presence of multidrug-resistant organisms, and breaks in infection prevention and control activities
- these result from the delivery of health services in a health care facility
What is endogenous?
- occurs when part of the patient’s flora becomes altered and an overgrowth results
- often happens when a pt receives broad spectrum antibiotics that alter the normal floras(yeast, staphylococci, enterococci, and streptococci)
How does tissue repair work?
*healing involves the defensive, reconstructive, and maturative stage
What are the sites for health care associated infections?
urinary tractsurgical or traumatic woundsrespiratory tractbloodstream
How does age factors influence a patient’s susceptibility to infection?
*infants have immature defenses, breastfed babies have greater immunity, viruses are common in middle aged adults, older adult cell mediated immunity declines