NORMAL FLORA PT 1

• Normal Flora


  Microorganisms normally living on or in the body without normally causing disease
• Resident flora


  Microbes that are always present on or within the body
• Transient flora


  Microbes that live in or on the body for a period of time then move on or die off
• Carrier state


  State of being a carrier of pathogenic organisms; that is, one who is infected but free from disease
• A fetus is sterile when born
• Our internal organs are sterile like the spleen, liver, pancreas, bladder, Cerebrospinal Fluid, and blood unless during infection
• Normal flora differ from one human to another depending on age, diet, and geographic habitat
• When the number of resident normal flora is greatly reduced, opportunistic microbes can easily cause infections in these areas e.g. Candida Albicans that cause candidiasis
• Symbiosis


  The relationship between the normal flora and the host
• Types of symbiotic relationships between bacteria and host

  • Mutualism
  • Commensalism
  • Parasitism
• Mutualism


  Where both the host and bacteria are thought to derive benefits from each other
• Commensalism


  Where one organism benefits and the other is unaffected
• Parasitism


  When one organism benefits at the expense of the other organism
• Factors that affect normal Flora

  • Weather
  • Age
  • Personal hygiene
  • Sex
  • Diet
  • Standard of living/nutritional status
  • Health
  • Hospital stays
  • Clothing
  • Environment
• Advantages of Normal Flora

  • They constitute a protective host defense mechanism by occupying ecological niches
  • They produce vitamin B and vitamin K in intestine
  • The oral flora contribute to immunity by inducing low levels of circulating and secretory antibodies that may cross react with pathogens
  • The oral bacteria flora exert microbial antagonism against nonindigenous species by production of inhibitory fatty acids, peroxides, bacteriocins, etc.
  • The normal flora may antagonize other bacteria through the production of substances which inhibit or kill nonindigenous species
• flora

  • collective bacteria/microorganism in a host
• pathogenicity

  • ability of parasite to inflict damage on host
• virulence

  • measures pathogenicity
• disease

  • damage to host that impairs host to function
• infection

  • microorganism is established and growing in a host
• jain darma

  • postulated existence of nigodas
• Marcus Terentius Varro

  • roman scholar
  • has a book called the unseen creatures animacules
• Avicenna

  • suggested tuberculosis and other disease might be contagious
• Akshamsaddin

  • turkish scientist
  • work called "the material of life"
• girolamo fracastoro

  • proposed epidemic disease could transmit infection by indirect or direct contact
• Leeuwenhoek

  • father of microbiology
  • first to conduct experiments on microorganisms
• Louis Pastuer

  • disgree with theory of spontaneous generation
  • supported theory of disease
• robert koch

  • microorganisms can cause disease
  • bacillus anthracis
• john hogg

  • naming third kingdom called protoctista
• ernst haeckel

  • renamed protoctista to protista
• Beijerinck

  • one of founders of virology and environmental microbiology
• Sergei winogradsk

  • developed concept of chemolithotrophy
• felix d'herelle

  • co discovered bacteriophages
• bacteriocin

  • antibacterial peptides/proteins that kill or inhibit growth of closely related bacteria
• normal flora differ from one human to another
• human gut contains 40,000 bacterial species
• human body contains around 1013 cells
• human physical structure contains 1014 bacteria
• candida albicans cause candidiasis
• normal flora is located in...

  • skins
  • eyes
  • nose
  • mouth
  • ears
  • genitourinary tract
  • alimentary canal