Bacterial Diseases

_____ gram+ cocci in grape-like clusters; facultative anaerobes; catalase positive; can withstand high salt concentrations (7.5 -10 %), extremes in pH, drying, and relatively high temperature (60 °C for 60 mins).

Straphylococcus

This bacterium can be found on the surface of our skin and 20% of people who have this bacterium permanently present in their nostrils are considered carriers

Staphylococcus aureus

Cutaneous infections associated with skin, hair, and nails. Can cause impetigo of newborn or scalded skin syndrome.

Staphylococcus aureus

______ a gram-positive cocci in chains of two or more (in liquid cultures): facultative anaerobes; catalase negative (have peroxidase to inactivate H2 O 2 ); commonly separated based on serological differences in cell wall carbohydrates and on type of lysis of red blood cells.

Streptococcus

_____ most serious pathogen in group A on serotyping. (pyogenic means pus producing.) Found in throat, nasopharynx and sometimes on the skin of humans.

Streptococcus pyogenes

Causes strep throat

Streptococcus pyogenes.

This organism can cause autoimmune complications. This can lead to Arthritis and fever. Can cause irregular movement termed saint vitus dance.

Streptococcus pyogenes

Can cause “flesh-eating disease”

Streptococcus pyogenes

If this organisms strain is lysogenized, it may produce an erythrogenic toxin that is spread throughout the body causing high fever and a red rash all over the body, called
scarlet fever.

Streptococcus pyogenes

This organism is found in the oral cavity. Destroys enamel by fermentation of sugars to acid.

Streptococcus mutans

cause 60 – 70 % of all bacterial pneumonias. Must be encapsulated to be pathogenic (S strains have smooth colonies), which makes them resistant to phagocytosis

Streptococcus pneumoniae

____ usually only a problem if normal defenses weakened (part of our normal flora). Can cause wound and skin infections, neonatal infections, puerperal infections, and streptococcal endocarditis.

Streptococcus agalactiae

Part of normal flora in large intestine. Can occasionally cause infections of the urinary tract, wounds, blood, appendix, and endocardium. Post-surgical infections with this organism are quite common.

Enterococcus faecalis (streptococcus)

_____ gram-negative diplococci; pathogenic strains are usually encapsulated and are very fastidious, requiring enriched media and growth in an atmosphere rich in CO2 .

Neisseria

____ almost always an STD except for neonatal cases where the newborn infant is infected as it passes through the birth canal. Organisms attach to mucous membranes of the urethra, vagina, eyes, throat, etc. and then invade the underlaying connective tissue

Neisseria gonorrhoeae

Newborn infant can get infected as it passes through the birth canal. Can lead to blindness. Infants given silver nitrate eye drops to prevent eye infection.

Neisseria gonorrhoeae

_____ cause epidemic meningococcal meningitis. Carriers harbor the organism in their nasopharynx and pass it to others by droplets. After an initial bout of pharyngitis, the organism in some cases will enter blood and migrate to the meninges causing a potentially lethal condition.

Neisseria meningitidis

The vaccination for this is recommended for college students. This disease can cause severe sepsis which displays as a purple rash. Carriers harbor the organism in their nasopharynx

Neisseria meningitidis

infections from animal bites (dogs, cats), leading to skin/wound infections, but can result in severe issues like necrotizing fasciitis, compartment syndrome, pneumonia (in animals and humans), and systemic infections, often by opportunistically infecting trauma sites or compromised immune systems, acting as a zoonotic pathogen

Neisseria animaloris

Aerobic – Bacillus (Gram-positive, catalase-positive, endospore-forming, rods common in soils etc.). Large number of species, but only two are pathogenic in normal individuals

Gram+ bacillus

This organism has 3 types: cutaneous, gastrointestinal, and pulmonary. The pulmonary disease is commonly called Woolsorters disease.

Bacillus anthracis

Spores can germinate in food and vegetative cells produce enterotoxin; very similar to S. aureus food poisoning.

Bacillus cereus

Although the infections caused b are rare, they may occur as Bacteremia and Meningitis.

Bacillus megaterium

Gram-positive, catalase-negative, endospore-forming rods {often with swollen sporigium}, also common in soils, etc.). These organisms produce some of the most potent toxins known and cause two types of diseases – wound and tissue infections, including colitis; and food intoxications.

Clostridium species

Gas gangrene – cause by ___, ____, ___ Endospores enter wounds and germinate. As the organism grow in dead or damaged tissue, where anaerobic conditions exist, produce gas from fermentation of muscle carbohydrates and release exotoxins that cause
cell destruction including collagenase, hyaluronidase, DNase, and lecithiniase that destroys membranes.

Cl. perfringens, Cl, novyi, Cl. septicum.

Antibiotic-associated colitis – __________, which is a normal inhabitant of the large intestine, can superinfect the intestine if the other flora are wiped out by antibiotics. The organisms produce an enterotoxin that causes inflammation of the colon and diarrhea.

drug resistant strains of Cl. difficile

Tetanus enter deep puncture wounds, burns, etc. and germinate in anaerobic area. As they grow the cells produces a potent neurotoxin called tetanospasmin or
tetanus toxin.

Clostridium tetani

This organism is a gram + endospore former. The toxin is released from dead cells and causes severe muscle spasms often in the back or jaw (“lock Jaw”).

Clostridium tetani

Food intoxication occurs when the spores of _____ in foods such as canned vegetables, meats, or cheese are not killed by processing. If anaerobic condition exist,
the spores can germinate, grow, and produce botulin or botulism toxin, probably the most toxic substance known.

Clostridium botulinum

The toxin that this organism creates can be used cosmetic treatments and is called Botox.

Botulinum toxin (Cl.)

This organism can cause intestinal infections when infants are given honey.

Clostridium botulinum

Similar to B. cereus and S. aureus food poisoning except that most of the enterotoxin is not produced in the food but after the organism is ingested and sporulates in the intestinal tract.

Clostridium perfringens

short (coccobacilli) to long rods as single cells or in chains. Motile with 1-4 flagella. Causative agent of listeriosis, which in healthy adults may be asymptomatic or result in mild fever, diarrhea and sore throat.

Listeria monocytogenes

Adding to the problem is the act that ____ is one of the few pathogens that can grow at refrigerator temperatures, meaning its numbers can increase during a food’s normal shelf life. Adequate pasteurization or cooking are the best methods of control.

Listeria monocytogenes

This organism is common in contaminated meat, poultry, and especially dairy products. It is excreted in the feces and can grow at refrigerator temperature.

Listeria monocytogenes

Infection in the throat from this organism causes inflammation, fever, and the production of a grayish pseudomembrane

Corynebacterium diphtheriae

Causative agent of diphtheria. Organism typically is contracted from airborne droplets from carriers or individuals with an active infection or from contaminated fomites. Initially get a localized infection in the throat.

Corynebacterium diphtheriae

Acid-fast positive often filamentous rods that are gram-nonreactive unless outer waxy coat is removed, and very slow growing. Outer waxy coat makes them more
resistant to germicides and drying. Two members of this genus are of primary importance as human pathogens (although others also can cause disease).

Mycobacterium

Causes tuberculosis. Transmitted through droplets in air and can survive for months in aerosol particles. As many as on-half of the world’s population may carry organism, but infection rate is low

Mycobacterium tuberculosis

This organism does not grow in artificial media. Transmission requires prolonged contact with the infected person. Causes leprosy

Mycobacterium leprae

common soil organisms; metabolically very versatile as to C source. Opportunistic pathogens especially in nosocomial (hospital acquired) infections. Very resistant
to soaps, detergents, disinfectants and drying.

Pseudomonas

_____ is the most important of this group
medically. Introduced by medical procedures (catheterization, injections) or gets into wounds,
especially burns. Found everywhere in the hospital environment, including ventilators, humidifiers, bathroom fixtures, etc.

Pseudomonas aeruginosa

This organism is a gram-negative aerobic rod. It has the toxin pyocyanin, which results in a blue-green pus.

Pseudomonas aeruginosa (sp.)

causes brucellosis, primarily a disease of animals such as cattle and pigs, but they can pass it to humans (thus a zoonosis).

Brucella species

which cause infections of the placenta and fetus and result in abortion in these animals, are of most concern.

Brucella abortus (cattle) and B. suis (pigs),

Those organisms can enter through broken skin or though mucous membranes in the eyes, digestive tract, or
respiratory tract. Initially they enter the lymph system and then into the blood, where they can spread to liver, spleen, kidneys, bone marrow, etc. Symptoms include fluctuating fever (hence the term undulant fever), chills, sweating, body aches, weakness and weight loss but not abortion in humans.

Brucella species infections in humans

cause tularemia or “rabbit fever”. Primarily an animal disease (rodents, rabbits, skunks, opossums, etc.) but can be passed to man (thus another zoonosis) by insect and arthropod vectors suck as deer flies, ticks, and mosquitos or by handling animal skins and meat or inhaling dust.

Francisella tularensis

This organism impairs our ciliary elevator and causes death to our alveolar macrophages. This is most deadly to young children due to their immature respiratory system.

Bordetella pertussis

causative agent of pertussis or “whopping cough”. Transmission occurs by inhalation of droplets from others with infection; usually a disease of very young children.
Estimated that about 95 % of world’s population has had disease.

Bordetella pertussis

This organism is widely distributed in aquatic environments and causes legionnaries’ diseases and Pontiac fever.

Legionella pneumophila

This organism is widely distributed in aquatic environments and the soil and can be found in virtually any water-containing device including air conditioners, cooling towers, hot water heaters, shower heads, etc. (Legionnaires’ disease and Pontiac fever)

Legionella pneumophila

Causative agent of plague (bubonic plague or the Black
Death). A zoonosis, the organism infects 100s of different animals, especially rodents, which do not die from infection and serve as a reservoir of the infection for other animals, and is spread to other animals, including man, by flea bites

Yersinia pestis

____ causes acute bacterial meningitis. Primarily a disease of young children or elderly who probably are infected by adult carriers of the organism. Also can cause respiratory tract infections and middle ear infections.

Haemophilus influenzae

_____ causes “pinkeye” or acute communicable conjunctivitis. Hemorrhage caused by the infection gives the sclera (white of the eye) a bright pink color.

Haemophilus aegyptius

_____ causes the STD known as soft chancre or chancroid. Lymph nodes in the genital area develop into bubo-like swellings that may burst from the swelling.

Haemophilus ducreyi

part of the normal flora in the mouth and nasopharynx,
they can be introduced into the blood during routine dental procedures, periodontal disease or oral injury and cause endocarditis in individuals with heart disease.

H. parainfluenza and H. aphrophilus

a large group of small gram-negative rods found in animal intestines. Primarily cause infectious diarrhea. Secretory or toxigenic diarrhea –the organisms grow on the surface of intestinal epithelial cells and produce an enterotoxin that
binds to these cells and causes loss of water and electrolytes; (2) invasive diarrhea or dysentery – the organisms invade the intestinal epithelium causing ulcerations, loss of intestinal lining, blood in stool, fluid loss

Enterics

This organism causes the STD known as soft chancre sore. Co infection with herpes simplex and syphilis is common.

Haemophilus ducreyi

Infants have less well-established microflora in their intestinal tracts and undeveloped immune systems and are prone to this disease.

Infantile diarrhea caused by enteric pathogens.

May be caused by virus, protozoa, or bacteria, but most cases are probably due to enterotoxigenic strains of E. coli to which the local population is immune.

Traveler’ diarrhea

a new strain of E. coli called O157:H7 has emerged that produces a powerful exotoxin that causes severe gastroenteritis, bloody diarrhea, and in some cases severe kidney damage and death. The toxin appears to be identical to shigatoxin. The disease is acquired primarily by ingestion of undercooked hamburger.

Hemorrhagic colitis/hemolytic uremic syndrome

50 -80 % of ______ are probably caused by E. coli. Women especially tend to have this problem.

Urinary tract infections (UTIs)

can cause lung infections, UTIs, meningitis, wound infections, and bacteremia.

Klebsiella pneumoniae

____ is a common cause of UTIs; also can cause wound infection and bacteremia.

Enterobacter aerogenes

______ can cause pneumonia, burn and wound infection, and septicemia.

Serratia marcescens

_____ can cause UTIs and bacteremia.

Citrobacter freundii

_____ causative agents of salmonellosis, infections primarily of the small intestine. Several species important here.

Salmonella

_____ cause typhoid fever. At one time the most important
salmonellosis. Organism is ingested in fecally contaminated food or water. Symptoms include high fever, diarrhea, abdominal pain, with intestinal bleeding and perforation of the intestine and septicemia in some patients.

Salmonella typhi

These are zoonotic strains that contaminate meat (esp. poultry) and animal products (esp. eggs).

S. enteritidis

____ causative agents of shigellosis or bacillary dysentery, primarily an infection of the large intestine. Several species, including Sh. dysenteriae, Sh, flexneri, and Sh. sonni are important here. Symptoms include abdominal cramping and blood and mucous in the stool.

Shigella

_____ causative agent of syphilis, which is primarily an STD (except for congenital syphilis, which is passed from an infected women to the fetus; this condition
can result in miscarriage, stillbirth, or severely disfigured infants) and afflicts only humans.

Treponemes pallidum

causative agent of leptospirosis, a zoonosis that humans can acquire form wild animals (skunks, racoons, rodents, etc.) and from domesticated animals (dogs, cattle, pigs, horse). Primarily a tropical disease, the organism is shed in the urine of infected animals and infection probably results from contact with urine through damaged skin or mucous membranes.

Leptospira interrogans

an cause a purple rash that appears on the skin (called petechial rash)

Leptospira interrogans

______ causative agent of Lyme disease. The organism is transmitted to man by a tick bite, especially deer ticks in the genus Ixodes. The ticks acquire their infection from the white-footed mouse (usually) or deer. A characteristics bull’s-eyerash usually develops at the site of initial infection followed by fever, headache, stiff
neck, and dizziness.

Borrelia burgdorferi

_____ causes tick-borne relapsing fever. Animal reservoir is squirrels, chipmunks and other wild rodents. ______ cause louse-borne relapsing fever. Humans are the only reservoir.

Borrelia hermsii; B. recurrentis

_____ causative agent of cholera. Short, curved gram-negative rods with comma shape. Spread by fecal contamination of food or water; may also be free living in some parts of world. The organism also can be found in
crustaceans, which serve as animal reservoirs, and the disease can be contracted by eating undercooked shellfish.

Vibrio cholerae

causes a gastroenteritis commonly associated with eating raw or undercooked seafood. The organism grows in marine coastal waters and colonizes the chitinous shells of shellfish such as shrimp, crabs, lobsters.

V. parahaemolyticus

causes a gastroenteritis and secretory diarrhea. Passed to humans from animal reservoir (sheep, cattle, wild birds, dogs and especially chickens) or from other people through fecally contaminated food or water. The organism multiplies in the small intestine and produces an enterotoxin,

Camphylobacter jejuni

_____ causes gastritis (inflammation of stomach lining) and most stomach ulcers, which can lead to stomach cancer. Many people carry the organism and are asymptomatic. Animals (esp. cats) may be a significant reservoir. Organism may be acquired by oral-fecal and oral-poral routes.

Helicobacter pylori

_____ causative agent of Rocky Mountain spotted fever. A number of wild and domestic animals (incl. dogs) can serve as a reservoir for this organism. It is passed to man by bite from ticks. The organism enters endothelial
cells in lining of small blood vessels and causes necrosis of this lining.

Rickettsia ricketsii

____ causes Q fever, which has symptom similar to RMSF without the rash. Organism is passed between animals by tick bites but usually to man by urine, feces, airborne particles, meat or unpasteurized milk. Infection can be acquired by ingestion or through lungs, skin or eyes.

Coxiella burnetti

____ primarily a cause of eye infections and STDs, including nongonococcal urethritis (NGU) in males and pelvic inflammatory disease (PID) in females, probably the most common sexually transmitted bacterial disease in this
county; and lymphogranuloma venereum, which is caused by more virulent strains of the organism that infect lymph nodes with obstruction of the lymph channels that leads
to formation of buboes in the genital region.

Chlamydia trachomotis

_____ causes chlamydial pneumonia, a generally mild respiratory infection. About 50 % of all adults over the age of 50 have antibodies against this organism. This is significant because recent studies suggest that from one-half to two- thirds of all heart attacks may be caused by infections by this organism.

Chlamydia pneumoniae

____ causes about 20 % of all pneumonias and one of the most common cause of primary atypical pneumonia in man. (Atypical means that no pneumococci, the most common cause of pneumonia, can be isolated from the
patient.). The organism is acquired by inhalation of airborne droplets; probably fewer than 10 % of those exposed show symptoms.

Mycoplasma pneumoniae

___ causes STDs including urethritis, prostatitis, vaginitis, pelvic inflammatory disease, kidney inflammation, and
can lead to miscarriage or stillbirth.

M. hominis and Ureaplasma (formerly Mycoplasma) urealyticum