MELS223 Lecture Notes - Lecture 8: Aminoglycoside, Cryptosporidiosis, Water Purification
Document Summary
Microorgansm that spends substantial part of life cycle outside human hosts but when introduced to humans cause disease with measurable frequency Microbes that can survive in the environment for a long period at ambient temperature while remaining infectious . Native soil or water organisms opportunistic infections in a susceptible host. Animal/human pathogens or normal microbiota may or may not replicate, often obligate parasites. Can be found as part of normal microbiota gut, skin (50% of us) Really important organism in hospital acquired infection. Can get through cuts on skin tube down cilia, immune deficiently. Cf can"t remove mucous which get colonized by this organism. Broad spectrum antibiotics (gram positive and negative both affected) over growth occurs due to this. Alginate (slime) / polysaccharide (capsule: eps glue that holds biofilm together. Immune evasion physical barrier against phagocytes, complement, antibodies. Once colony made, metabolic pathways slows down- antimicrobials difficult to work on. Invasins elastase destruction of elastin-containing tissues.