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• Gram positive bacteria -

  Staphylococcus aureus – found on skin and not cause health issue. Some strains can be highly pathogenic. Health concern is the S.aureus resistance.

  Strepococcus pyogenes – common cause of sore throat. Can also cause meningitis and pneumonia.
• Gram positive – bacillus antracis – transmissible from humans to farm animals.

  It infects both humans and livestock. Forms spores and can resist harsh conditions. Reactivated when it enters host cell. Enter human body through skin, inhalation or ingestion.

  Prevented by burning and slaughtering livestock.
• Bacilli clostridium tetani – is a neurotoxin which causes convulsion contractions of voluntary muscles. Causes lockjaw.
• Clostridium botulinum – is a neurotoxin and causes respiratory paralysis. Causes severe food poisoning due to improper storage of food.

  Also produces Botox for cosmetic use and treating diseases with muscle spasm.
• Vibrio cholerae – causes cholera and diarrehea due to feces contaminated water.

  Infects humans. Contracted by ingesting item washed with contaminated water. It can survive fresh and salty water.
• E.Coli – most are harmless and live in our gut to aid digestion. Some strains cause food poisoning, diarrhea, gastroenteritis and sometime UTI’s.

  Serious in children and elderly patients.
• Salmonella eneterica – is food borne pathogen. Cause severe food poisoning due to improper storage of food. Causes abdominal cramps, fever, vomiting, diarrhea. Severe in elderly, children and immuno compromised patients.
• Salmonella typhi – subset of Salmonella enterica. Causes typhoid fever. Due to contaminated food and water. Common in areas with poor sanitation. Causes abdominal pain, vomiting, rashes, fever. Reduced by improved sanitation, antibiotics and vaccination
• Mycoplasma Pneumoniae – simplest cells. Lack cell wall which helps them to be resistant to antibiotics that target enzymes forming cell walls.

  Found in urogenital and respiratory tract in humans.
• Bacteria Rickettsiae – obligate intracellular parasite that needs to grow on living cells. This causes rash, fever, tick bites and sometimes partial paralysis or gangrene causing amputation. Can be prevented through antibiotics and using insecticide sprays
• Chlamydiae – obligate intracellular parasites. They are gram negative cell wall. They cause severe conjunctivitis which can lead to blindness if not treated properly.

  It is a common STD and cause cause infertility and discharge. In males in can cause painful urination and reactive arthiritis and for females it can cause ectopic pregnancy and infertility.
• 4 main action mechanisms of antimicrobial drugs –

  1)Cell wall synthesis inhibition – due to internal osmotic pressure the cell lysis. Caused by penicillin and vancomycin

  2)Cell membrane function inhibition – eukaryotic and prokaryotic cell membrane difference.

  3) Protein synthesis inhibition – uses difference between prokaryotic and eukaryotic ribosomes

  4) Nucleic acid synthesis inhibition – inhibits various aspects of RNA and DNA synthesis (enzymes – RNA polymerase)
• Antibiotic use dangers – hypersensitivity to drugs which can cause rashes and fever.

  Superinfection from the drugs resistant pathogens

  Covers serious infections without treating the symptoms can be suppressed but infections may worsen

  Drug toxicity and Drug resistance which are more difficult to control