Micro Organism Flashcards
Saprophyte and parasite
*free living organism in dead and decaying matter.Normally no no infection but cause disease when defense mechanism is lowered
*lives in host and derives food from thehist without harming the host
Commensal
Cmplte harmony without causing any harm to hist
Eg,staphylococcus(skin)
Pathogen
Micro organism causing disease in host
Opportunistic pathogen
Commensal/pathogen
When host resistance is low, it cause disease
Pathogenisity
Ability to cause infection
Virulence
Degree of pathogenesity
How microbe cause infection
Entering and multiplication in the body
Types of infection -5
-1o,initial infectionin a host with a parasite
-Reinfection, subsequent infection by same parasite
-2o ,when body resistance low due to pre existing infectious disease,new parasite cause infection
-Cross infection ,patient already suffering from a disease acquire infection from another host
-nosocofial, hospital acquired
Another 5 infection
-inatrogenic,physician induced infection resulting in truck therapy or investigative procedures
-subclinical, when clinical symptoms are not cleanly visible
-latent,parasite remains in hidden state in host which proliferate and shows clinical symptoms when host immunity is lowered
-atypical, clinical symptoms/manifestation of a particular disease is absent
Transmission of infection
Reservoir or source of infection -human,soil,insect,water or inanimate in which parasite lives and multiplies
2 types, exo and endo
Endogenous reservoir
Organism of normal flora occasionally pathogenic normally non pathogenic
Eg,staphylococcus, e.coli
Exogenous reservoir
Human cases,carriers, animals,insect,soil, water and food
Carrier. Different types
Harvest pathogenic organism without suffering from its ill effects
Types
*healthy -carries pathogenic but not affects from it
*condolence-recovered from infection but continue carrying organism
Depending on duration
*temporary- stay for less than 6 months
*chronic -for several years or even rest of one’s life
*paradox-accure pathogen from another carrier
*contact -accure pathogen from a patient
Reservoir from animal
Source-animals
Assymptamatic but act as reservoir of human infection known as reservoir host
Zoonotic disease-infectious disease transmitted from animal to man
Eg,helminthic, bacterial, viral,fungal,protozoan
Insects causing infection
Mosquito, ticks,flies,mice