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 Pseudomonas – an opportunistic pathogen  Brucella & Francisella – zoonotic pathogens  Bordetella & Legionella – mainly human pathogens  Alcaligenes – opportunistic pathogen 3

 Small gram-negative rods  Single polar flagellum  Free-living  Found soil, sea and fresh water  Normal flora (10% population) 4

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 Common inhabitant of soil & water  Intestinal resident in 10% normal people  Resistant to soaps, dyes, ammonium disinfectants, drugs, drying  Frequent contaminant of humidifiers, ventilators, IV solutions, anesthesia equipment  Opportunistic pathogen Usually doesn’t cross healthy dry tissue Healthy -- skin rash, ear infection, UTI, Common cause of nosocomial infections in hosts with burns, neoplastic disease, cystic fibrosis 6

 Complications include pneumonia, UTI, abscesses, otitis, corneal disease  Systemic --endocarditis, meningitis, bronchopneumonia (80% fatality)  Will have a grapelike, very sweet odor  Greenish-blue pigment (pyocyanin) found in pus  Multidrug resistant  Treated with cephalosporins, aminoglycosides, carbenicillin, polymixin, quinolones, & monobactams 7

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9 WARNING! GROSS PICTURE!

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Tiny gram-negative coccobacilli  2 species Brucella abortus (cattle) Brucella suis (pigs) Brucella canis (dogs)  Brucellosis, Malta fever, Undulant fever, & Bang disease – a zoonosis transmitted to humans from infected animals 11

 Fluctuating pattern of fever, chills, sweats, malaise, headache, joint pain, weight loss  Combination of tetracycline & rifampin or streptomycin  animal vaccine available  potential bio-terrorism agent 12

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 Small rod with bipolar staining  Causes tularemia, a zoonotic disease of mammals endemic to the northern hemisphere, particularly rabbits  Transmitted by contact with infected animals, water & dust or bites by vectors (ticks)  Headache, sores, backache, fever, chills, malaise & weakness  10% death rate in systemic & pulmonic forms  Intracellular persistence can lead to relapse  Treated with gentamicin or tetracycline  attenuated vaccine 16

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 Minute, encapsulated coccobacillus  Causes pertussis or whooping cough, a communicable childhood affliction  Acute respiratory syndrome  Often severe, life-threatening complications in babies  Reservoir – apparently healthy carriers  Transmission by direct contact or inhalation of aerosols 19

 Virulence factors receptors that recognize & bind to ciliated respiratory epithelial cells toxins that destroy & dislodge ciliated cells  Loss of ciliary mechanism leads to buildup of mucus & blockage of the airways  Vaccine – DTaP- acellular vaccine contains toxoid, Dtap is given for a booster 20

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 Known as Legionnaires disease & Pontiac fever Named in 1976, Philadelphia convention of American Legion  Widely distributed in warm water  Live in close association with amoebas  More prevalent in males over 65 22

 Nosocomial disease in elderly patients  Not spread person to person  Fever, chills, cough, diarrhea, abdominal pain, pneumonia  Fatality rate of 5-30%  Around 20,000 a year hospitalized in US  Treated with Azithromycin 23

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 Group known as Enterics  Large family of gram-negative bacteria  Many members inhabit soil, water, & decaying matter & common occupants of large bowel of humans & animals  All members are small, non-sporing forming rods  Facultative anaerobes, grow best in air  Cause diarrhea through enterotoxins  Divided into coliforms (lactose fermenters) and non-coliforms (non lactose fermenters) 25

 H – flagellar Antigen  K – capsule &/or fimbrial Antigen  O – somatic or cell wall Antigen  Endotoxin – shock and then death  Exotoxins – different symptoms 26

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 Most common aerobic & non-fastidious bacterium in gut  Enterotoxigenic E. coli causes severe diarrhea due to heat-labile toxin & heat-stable toxin – stimulate secretion & fluid loss; also has fimbrae  Enteroinvasive E. coli causes inflammatory disease of the large intestine  Enteropathogenic O157:H7 strain causes hemorrhagic syndrome & kidney damage 28

 pathogenic strains frequent agents of infantile diarrhea – greatest cause of mortality among babies  causes ~70% of traveler’s diarrhea  causes 50-80% UTI  indicator of fecal contamination in water - coliforms 29

 Klebsiella pneumoniae– normal inhabitant of respiratory tract, has large capsule, cause of nosocomial pneumonia, mennigitis, bacteremia, wound infections & UTIs  Enterobacter – UTIs, surgical wounds  Serratia marcescens – produces a red pigment; causes pneumonia, burn & wound infections, septicemia & meningitis 30

 Swarm on surface of moist agar in a concentric pattern  Cause UTI, wound infections, pneumonia, septicemia, & infant diarrhea 31

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 Motile; ferments glucose  Resistant to chemicals –bile & dyes  S. typhi – typhoid fever – ingested bacilli (feces) adhere to small intestine 1 wk-1 month incubation Headache, fever, abdominal pain, rose- colored rash, malaise, diarrhea Lasts for up to three weeks Can cause invasive diarrhea that leads to septicemia Intestinal rupture 33

 Asymptomatic carriers (gall bladders)  Extended antibiotic treatment  2 vaccines (50-75 % effective)  Typhoid controlled by: Proper sewage disposal Pasteurization of milk Maintenance of unpolluted water supplies Identification and treatment of infected individuals Monitor food handlers Removal of gall bladder 34

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 S. enteritidis – 1,700 serotypes- salmonellosis – zoonotic Most common cause of food borne disease in US Common flora of cattle, poultry, rats, mice 6-48 hrs incubation period Headache, chills, abdominal pain, nausea, vomiting, diarrhea, fever Last 1 – 5 days Self-limiting No antibiotic treatment recommended 36

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38 Reports of Salmonella Outbreak Investigations from 2014 Cucumbers – Salmonella NewportCucumbers Bean Sprouts – Salmonella EnteritidisBean Sprouts Nut Butter – Salmonella BraenderupNut Butter Clinical and Teaching Microbiology Laboratory Exposure – Salmonella TyphimuriumClinical and Teaching Microbiology Laboratory Exposure Organic Sprouted Chia Powder – Salmonella Newport, Salmonella Hartford, and Salmonella OranienburgOrganic Sprouted Chia Powder Frozen Feeder Rodents – Salmonella TyphimuriumFrozen Feeder Rodents Live Poultry –Salmonella Infantis, Salmonella Newport, and Salmonella HadarLive Poultry Pet Bearded Dragons – Salmonella Cotham and Salmonella KisarawePet Bearded Dragons Tyson Chicken – Salmonella HeidelbergTyson Chicken Raw Cashew Cheese - Salmonella StanleyRaw Cashew Cheese

 Shigellosis – bacillary dysentery  S. dysenteriae, S. sonnei, S. flexneri & S. boydii  Produce hydrogen sulfide  invades villi of large intestine, can perforate intestine or invade blood  Usually confined to large groups– military, institutions, reservations Can be sexually-transmitted by oral-fecal route Enters Peyer’s patches which instigates inflammatory response; endotoxin & exotoxins Severe symptoms: lesions in the intestinonal mucosa Abdominal cramps, vomiting, fever and diarrhea Bloody stools  Treatment – fluid replacement & ciprofloxacin & sulfa- trimethoprim 39

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 Nonenteric  Tiny, gram-negative rod  Unusual bipolar staining & capsules  Virulence factors – capsular & envelope proteins protect against phagocytosis & foster intracellular growth coagulase, endotoxin, murine toxin 41

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 Humans develop plague through contact with wild animals (sylvatic plague) or domestic or semi-domestic animals (urban plague) or infected humans  Found in 200 species of mammals  Flea vectors – bacteria replicates in gut of flea, coagulase causes blood clotting that blocks the esophagus; the flea becomes ravenous 43

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 3-50 bacilli  Bubonic – flea bite, enters lymph, causes necrosis & swelling called a bubo in groin becomes septicemic – progression to massive bacterial growth; virulence factors cause intravascular coagulation subcutaneous hemorrhage & purpura – black plague  Pneumonic – infection localized to lungs, highly contagious; fatal without treatment  Treatment: streptomycin, tetracycline or chloramphenicol  Killed or attenuated vaccine 45

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 tiny gram-negative pleomorphic rods  fastidious, sensitive to drying, temperature extremes, & disinfectants  none can grow on blood agar without special techniques – chocolate agar require hemin, NAD or NADP  some species are normal colonists of upper respiratory tract or vagina (H. aegyptius, H. parainfluenzae, H ducreyi)  others are virulent species responsible for conjunctivitis, childhood meningitis, & chancroid 49

 H. influenzae – acute bacterial meningitis, epiglottitis, otitis media, sinusitis, pneumonia, & bronchitis Subunit vaccine Hib  H. aegyptius –conjunctivitis, pink eye  H. ducreyi – chancroid STD  H. parainfluenzae & H. aphrophilus – normal oral & nasopharyngeal flora; infective endocarditis 50

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