25 Flashcards
Dental plaque
– Biofilms involved in the formation of dental caries
Streptococcus mutans
cariogenic: producing or promoting the development of tooth decay)
- Gram-positive coccus
- Converts sucrose to lactic acid
- Produces dextran, a polysaccharide that forms plaque
• Plaques attract other bacteria (e.g. Streptococci )
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Staphylococcus aureus
Causes infection in the lower respiratory system, by producing enterotoxins, is not inactivated by heat, temp. Abuse causes the toxin to be produced when incubated in food
Most active bacteria in high osmotic pressure and high temperature.
Shigellosis
Bacillary Dysentery)
• Caused by the genus Shigella
– Facultatively anaerobic; gram-negative – Four species
Salmonellosis
Salmonella Gastroenteritis) (1 of 2)
• Salmonella enterica
– Gram-negative, facultative anaerobe, nonendospore-
forming rods
– Normal inhabitant of the human intestinal tract and many animals
– 2000 serotypes
Typhoid Fever
Salmonella serotype Typhi
Cholera
Vibrio cholerae
– Slightly curved, gram-negative rod with single polar
flagellum
– Associated with salty waters – Produces the cholera toxin
Toxin causes the host cells to secrete electrolytes and water.
Causes “rice water stools”
Noncholera Vibrios
Vibrio parahaemolyticus
Escherichia Coli Gastroenteritis
Enteropathogenic E. coli (EPEC)
Enteroinvasive E. coli (EIEC)
Enteroaggregative E. coli (EAEC)
Enterohemorrhagic E. coli (EHEC)
Traveler’s Diarrhea
Most common cause is ETEC; second most common is EAEC
• Can also be caused by Salmonella, Shigella, and Campylobacter
Campylobacteriosis
(Campylobacter Gastroenteritis)
• Caused by Campylobacter jejuni
– Gram-negative, microaerophilic, spirally curved
• Leading cause of foodborne illness in the United States
– Common in the intestines of poultry
– 60% of cattle excrete organism in feces and milk
• Fever, cramping, abdominal pain, diarrhea, dysentery
• One in 1000 cases leads to Guillain-Barré syndrome
Guillain-Barré syndrome
autoimmune disease damaging peripheral nerves).
Caused by Campylobacter jejuni
Helicobacter Peptic Ulcer Disease
Helicobacter Peptic Ulcer Disease
Clostridium Difficile–Associated Diarrhea
Gram-positive, endospore-forming anaerobe
Mumps
Virus targets the parotid glands
