Cholera Flashcards
What are some facts about V. Cholera?
Incubation period is 1 to 3 days
Grows fast in Food
Resists salt but is sensitive to heat and acid
Infectious dose is 10 to the 6th to 10 to the 8th
what is the action of the V. Cholera toxin?
It activates the conversion of ATP to cAMP. cAMP causes the secretion of chloride and reduced absorption of sodium, Consequently the stool concentrations of Na, K, Cl and Bicarbonate are high.
What percentage of those infected are asx?
75%
What are the clinical finding of Cholera?
Dehydration/shock with doughy skin- Cholera Gravis
WHO definition:
Age>5 yrs
Acute watery diarrhea (3+ stools per day)
Severe dehydration
What factors predispose to Cholera infection?
Large inoculum ingested
Low stomach acid
Reduced Gut immunity
Blood type O
What clinical findings identify a person with severe dehydration?
Lethargy
Inability to drink
very slow return of skin pinch
What is the treatment of Cholera?
Fluids:
Isotonic crystalloid- for weight loss of >10%-replace over 2 to 4 hrs
ORT: for weight loss >5% (Na=90, Cl =80,HCO3=30, K =20
Cholera cot
Abx shorten course by 24 hrs
Mortality ranges from <1% to > 50%
How is cholera diagnosed?
Culture-Cary Blain TCBS culture media Serology to Toxin-lasts for yrs Serology to Vibrio- lasts for mos. Rapid dipstick
What is the definition of access to water?
availability of a source of water which can provide at least 20 liters per day which is 1 km or less from the patient’s home.
What are some ways of providing clean water?
Ceramic Filtration (Silver Impregnated)- potters fro peace
Biosand- slow sand filtration with removal of 90% of Viruses and coliform bacteria
Solar Disinfection (Sodis)-plastic bottles are painted blck to capture heat and UV light. Uses clean water. Takes 5 hours with bright sun and 48 hours with cloudt sky.
Flocculation and Chlorine- used for turbid water, costs 20cents per day. Add a packet and wait 20 minutes, then filter thru a white cloth
CDC Safe Water guard- add dilute bleach to 20 liters of water
What is the definition of access to water?
availability of a source of water which can provide at least 20 liters per day which is 1 km or less from the patient’s home.
What are some ways of providing clean water?
Ceramic Filtration (Silver Impregnated)- potters fro peace
Biosand- slow sand filtration with removal of 90% of Viruses and coliform bacteria
Solar Disinfection (Sodis)-plastic bottles are painted blck to capture heat and UV light. Uses clean water. Takes 5 hours with bright sun and 48 hours with cloudt sky.
Flocculation and Chlorine- used for turbid water, costs 20 cents per day. Add a packet and wait 20 minutes, then filter thru a white cloth
CDC Safe Water guard- add dilute bleach to 20 liters of water
What is the shape of the Cholera toxin?
It is pentagonal with a central core with structure A:5B
What is the receptor of the Toxin?
The Ganglioside receptor GM1. The binding is irreversible, the cells replace themselves every 3 to 5 days.
Is breast feeding protective against Cholera?
Yes, due to Lactoferrin, Lysozyme and antibodies.
