Infection Flashcards
what are some CONCERNS regarding infectious diseases?
- greater emergence of PREVIOUS UNKNOWN INFECTIONS
- a REemergence & SPREAD of old infections
- greater RESISTANCE to multiple antibiotics
what is the RELATIONSHIP between humans and microorganisms?
- creation of a NORMAL HUMAN MICROBIOME
- human body becomes a PRIMARY SITE OF GROWTH
- provides NUTRIENTS / produces ENZYMES for human digestion
- maintained by PHYSICAL BARRIERS
where can MICROORGANISMS be found on the human body?
- skin
- mouth
- gi tract
- resp. tract
- gu tract
symbiosis / symbiotic relationship
benefits only the HUMAN, no harm to the microorganism
mutualism
benefits BOTH HUMAN & MICROORGANISM
parasitism
benefits the MICROORGANISMS; HARMS the HUMAN
opportunism
- situation where BENIGN MICROORGANISMS become PATHOGENIC because of DECREASED HUMAN HOST RESISTANCE/translocation to other body sites
- seen when BARRIERS/DEFENSE SYSTEMS of the body grow WEAK
example of opportunism
- ex. antibiotics - can cause greater growth of opportunistic microorganisms and cause disease
- C. diff
- ex. autoimmune patients
what are the FIVE STEPS in the process of INFECTION?
- ENCOUNTER & TRANSMISSION
- COLONIZATION
- INVASION
- DISSEMINATION
- CELLULAR/TISSUE DAMAGE
what are the types of TRANSMISSION?
- can be either DIRECT or INDIRECT
vertical transmission
mom to child transmission during birth from the placenta
ex. Listeria monocytogenes, CMV
horizontal transmission
seen with transmission of blood, body fluids
spread from one person to another/animal
ex. HIV, zoonotic infections
indirect transmission
contact with INFECTED NON-LIVING MATERIALS
- towels, toys, bandages, doorknobs
contact with INHALATION/DROPLETS
ex. flu, pneumonia
contact with CONTAMINATED ITEMS
ex. cholera, gastroenteritis
definition of COLONZATION
- the ability of a PATHOGENIC MICROORGANISM to SURVIVE and MULTIPLY on or within the human environment
- competing with SYMBIOTIC MICROORGANISMS and RESISTING LOCAL DEFENSES
adherence
- helps to PROTECT the microorganism from REMOVAL from mechanical, non-mechanic, coughing forces
- often seen between RECEPTORS of the surfaces of cells/microorganisms
biofilms
- mixed species of microorganisms that have a HIGHLY ORGANIZED EXTRACELLULAR MATRIX produced by the microorganisms
- become more TOLERANCE & RESISTANT to antibiotics & immune responses
- can form ANYWHERE - medical devices (pacemakers, prosthetics, catheters)
invasion
- the ability of PATHOGENS to cross SURFACE BARRIERS including the SKIN & MUCOUS MEMBRANES
- needs PENETRATION to BREAK THE INTEGRITY of the surface barrier
dissemination
spread of infection that can occur by DIRECT EXTENSION through surrounding tissue or through the blood/lymphatic vessels
cellular/tissue damage
production of TOXINS or indirect results due to immune responses of inflammation, swelling, scarring, or necrosis
endogenous microorganisms
- already present within the body
- part of the normal microbiome
exogenous microorganisms
- transmitted from an EXTERNAL SOURCE
- ex. contaminated water, food, human, animals etc…
endemic
disease is RELATIVELY HIGH RATE, but has constant rates in a SPECIFIC POPULATION
epidemic
number of NEW INFECTIONS in a SPECIFIC POPULATION greatly exceeds the NUMBER USUALLY OBSERVED
pandemic
epidemic spread worldwide or over large area