Studied by 2 people
major species
V. cholerae V. parahaemolyticus V. vulnificus
gram stain / morphology
gram neg, curved rods
motility
monotrichous
unique characteristics
tolerates high pH. susceptible to low pH O antigen
V. parahaemolyticus, V. vulnuficus
transmission
clinical manifestation
treatment
raw fish --> gastroenteritis (common in Japan/SE Asia)
wound infections, septicemia --> Doxycycline + Cephalosporin
tissue necrosis, necrotizing fasciitis
V. vulnuficus --> gasteroenteritis --> septicemia
V. parahaemolyticus, V. vulnuficus - when do infections occur
summer
seafood contamination
water contamination doing water activities
V. cholerae - discovery
1884 R Koch 1854 J Snow made connection bw cholera outbreaks and water quality
V. cholerae - serotypes assoc w outbreaks
O1 and O139
O1 has no K antigen
V. cholerae - how many epidemics since what year? what serotype caused them where do outbreaks occur principal cause of outbreaks
7 major epidemics since 1816 caused by serotype O1 occur in underdeveloped countries principal cause - lack of access to safe water
V. cholerae - where is it found
bacteria multiply in water, high bac in feces of infected/recovering patients
V. cholerae - transmission
consumption of contaminated water in US - returning travelers/consumption of contaminated seafood
V. cholerae - infectious dose
high, 10^6-10^8
V. cholerae - clinical manifestations (what serotypes)
cholera (O1 and O139) gastroenteritis
cholera - symptoms
abrupt onset (2-3 days) watery diarrhea, vomiting "rice water" stools - colorless/odorless, speckled w mucus (high bac) up to 1L fluid loss hourly dehydration, cardiac/renal failure 60% mortality untreated
gastroenteritis symptoms, caused by what V. cholerae serotypes
mild diarrhea, self limiting non cholera toxin serotypes
V. cholerae pathogenesis - factors and what do they do
cholera toxin --> loss of water/electrolytes toxin co-regulated pilus --> adhesin colonization factor --> adhesin toxins that inc intestinal fluid secretion ToxR regulator?
V. cholerae diagnosis
McConkey - non lactose fermenter TCBS PCR based detection of toxin gene O antigen
what is TCBS
thiosulfate citrate bile salts sucrose
sulfate/citrate inhibit Entero
bile salts inhibit gram pos
V. cholerae treatment
replacement of fluids/salts - rehydration (ORS), drink as much as you lose sometime IV fluid replacement antibiotics to shorten course/reduce severity
Doxycycline for adults
TMS for children
what is ORS
oral replacement salts treatment for V. cholerae
V. cholerae prevention
sanitation food safety oral vaccine recommended during outbreaks
2 cholera vaccines, purpose and why its given
Dukoral, ShanChol offers short term protection during outbreaks to limit transmission
what is Dukoral
choler vaccine based on heat killed bacteria (O1) and cholera toxin B subunit
what is ShanChol
cholera vaccine based on heat inactivated bacteria (O1 and O139)
