Bacterial Pathogens Part 2 Botulism C botulinum Produces endotoxin commonly from food injestion food poisoning Occurs when food is canned improperly The spores begin to germinate when the environment becomes anaerobic resulting in the production of a very potent toxin Botulin A neurotoxin that affects the nervous system and interrupts neurotransmitters o Circulates to neuromuscular junctions o Prevents release of neurotransmitters o Skeletal muscles fail to contract o Causes paralysis Symptoms o Very little or no contraction of skeletal muscles flaccid paralysis o Muscles of head eyes and neck stop working first o Difficulty swallowing o Double vision o Muscles of limbs and respiratory system stop working properly o Arms and neck start to hang o Difficulty breathing leads to death from respiratory failure Bacteria can persist in nature where vegetation is anaerobic not just from canned foods Treatment o Passive immunization of antitoxin immune globin o Respiratory support o Person never has infection just active toxin in system o No antibiotics used for treatment Rare types of Botulism Wound infections botulism bacteria grows in wound very rare Infant Botulism infant gets infection and bacteria grows in the GI tracts and produces the toxin o Infants don t have much to protect their bodies like adults do o Infants most commonly get this infection from honey that contains botulism endospores Genus Mycobacterium Gram Aerobic filamentous rods long chains of branching cells Most harmless Many free living saprobes Grows in soil oral cavities and genitals Cell wall with mycolic acids Some commensals in soils with organic materials Slow growers with long doubling times days to weeks to months Tuberculosis M Tuberculosis One of the top most common pathogens out there Less and less cases present in the USA but still present Takes place world wide Morbidity 8 10 million people each year have tuberculosis Mortality 3 million people each have died from tuberculosis Most people have a natural resistance to disease Persists in environment through aerosols airborne transmission Bacteria sits and develops in lungs Bacteria is then engulfed by macrophages as the mycolic acids prevent the macrophage from destroying the tuberculosis bacterial Immune system reacts and big masses of cells form called tubercles The formation of tubercles then lead to lung damage Chronic disease Stages of Tuberculosis 1 Primary initial infection of the lungs Mild symptoms mild fever fatigue Most people recover but disease goes dormant Initial tubercles form no significant damage 2 Secondary Reactivation period Moderate severe lung damage Tubercles get larger and larger and start to damage Disease can spread to other organs Slowly progressive disease also called consumption Slow weight loss low fever extreme fatigue 3 Extrapulmonary Bacteria infects other organs through the bloodstream and forms tubercles in the bones kidneys brain and meninges Once reaches other organs it is fatal Prevention Early identification Mantoux Test tuberculin injection of mycobacterial proteins BCG vaccine The Pseudomonads Extremely common Gram bacilli Major plant and animal pathogens mostly plants Pseudomonas Aeruginosa Urinary Tract infection Most common infection Cutaneous and subcutaneous infections in burn patients Pneumonia in cystic fibrosis patients lungs aren t fully functioning they inhale bacteria and get pneumonia Treatment problems o One of the most antibiotic resistant bacteria o Potent enzyme producers o Pigment producers The Enteric Bacteria Family enterobacteracea Found in intestinal tract Most harmless commensals Gram facultative anaerobes Opportunistic pathogens Gain access to other sites Common cause of nosocomial and urinary tract infections Species o Escherichia coli E Coli most common o Klebsiella enterobacter proteus etc Strict Pathogens Much more dangerous o Strains of E Coli E Coli O157 H7 o Salmonella Salmonella Typhi typhoid fever o Non typhoid species all other species o Shigella o Yersinia pestis the plague black death
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