M4: topic 4: water-borne disease

• explain the agents and source of WBD

  1. it can = in variety of illness due to variety of pathogens
  2. common sources for transmission
  3. potable water
  4. recreational water
• define water as a res

  1. can be a source of large number of pathogens
  2. lepospria water contem with urine
  3. cytroporodium - pararsistic
• list non-feceal water

  1. legionella - water cooling systems, natural streams and air conditions
  2. pseudomonas
• what are coliforms 


  indicator organisms for screening and not for viral pathogens
• write the steps of testing coliform and e.coli

  1. enumerating the sample
  2. MPN produce and MF
  3. utilises proprietary sub-enzyme change <— looks at beta-glusocase
• resulting of screening for e.coli

  • sample clear = no coliforms
• Biosecurity

  • decrease the risk of spread of infections
  • preventative measures
  • react to outbreaks
• bioterrorism

  • intestinal or treated uses of microbes/toxins
  • delibrate
  • aim: death 


  ..
• cholera

  • transmitted by contaminated water
  • in developing countries
  • atatches to epithial cells in SI, grows and release entertoxin
  • dehydration = death
  • has o-groups
  • cells secrete muscinase = increase AMP
• Legionellosis

  • gram -ve bacteria
  • exist in biofilm
  • identified using flouresenct microscopy
  • cells grow within macrophage and monocytes
  • aersols
  • reistent to heat and chloride
  • treated with antibiotics
• Typhoid

  • pathogenic bacteria
• norovirus

  • GI illness
  • vom, dia, and malaise
  • treated with UV
  • transmitted in feacel
• e.coli

  • sometimes develops hemolytic urmeric sydeome which affects kidneys
  • transmission size is <100
  • adheres to host cell and colonise in LI
  • VEROXTOXIN
• crytosporidos

  • protist in a parasite in instesting
  • diarhhea
  • no therapeutic treatments
  • diagnosis through Florescent and PCR