Cholera

Question 1

Is cholera a notifiable disease?

Answer 1

Yes, it is nationally notifiable and urgent for labs and doctors

Question 2

What type of organism causes cholera?

Answer 2

Vibrio cholerae

Over 200 serogroups exist; toxigenic strains O1 and O139 cause cholera.

Question 3

How is cholera primarily transmitted?

Answer 3

Contaminated water or food, especially undercooked/raw seafood.

Large outbreaks associated with contaminated water.

Person to person transmission is rare.

Question 4

What are the clinical features of severe cholera?

Answer 4

• Often ASx or mild disease (esp children)
• Severe disease: profuse, painless, watery diarrhoea (rice water stools), vomiting, marked dehydration

CFR 50% without treatment, <1% with rehydration.

Question 5

What is the CFR of cholero without treatment?

Answer 5

50%
< 1% with rehydration

Question 6

Who are considered high-risk groups for cholera?

Answer 6

Children, older people

Question 7

What is the incubation period for cholera?

Answer 7

Hours to 5 days, usually 2-3 days

Question 8

How is cholera diagnosed?

Answer 8

Isolation of toxigenic V. cholerae serogroups O1 or O139 from stool or vomit

Requires special media and reference lab for typing/toxin results.

Question 9

What defines a cholera outbreak?

Answer 9

Single case if no history of overseas travel

Question 10

How common is cholero in Australia?

Answer 10

Rare - most cases overseas acquired

• Imported foods (seafood)
• Occasional local acquisition via contaminated rivers (O1 established in riverine environemnts in northern NSW, QLD but human disease rare)

Question 11

Where is cholera endemic?

Answer 11

Much of Africa and Asia.
Linked to inadequate WASH (water, sanitation and hygiene)

Question 12

What are the recommended preventive measures for cholera?

Answer 12

• Education for travellers on careful food and water consumption
• Cholera vaccine for certain high-risk individuals prior to travel to endemic areas - multi-dose oral vaccine

High-risk = humanitarian aid workers, IBD, gastric achlorydia, HIV/AIDS, immunocompromise

Question 13

What resources are available for public health management of cholera?

Answer 13

DH protocol
No SoNG

Question 14

How are cases of cholera managed?

Answer 14

Interview - DRSVECTA
* Specific travel hx, dates, locations; HGQ
* No travel - focus on imported/local seafood, river swimming

T - hospital, rehydration
I - food handlers no work until 2 x negative stool speciments 24hr apart
E - sx, transmission, prevention - food prep/hygiene

Question 15

What should be done for contacts of a cholera case?

Answer 15

T - NA
I - NA
M - monitor co-exposed, stool culture if symptomatic, test all household contacts
E - sx, transmission, prevention (WASH)

Question 16

What is the exclusion policy for food handlers in cholera cases?

Answer 16

No work until 2 negative specimens 24h apart

Question 17

What actions should be taken in the environment after a cholera case?

Answer 17

Urgent investigation of contaminated food and water supplies
* Remove - cleaning and disinfection of linen, terminal cleaning of hospital rooms,
* Reduce -
* Accept

Question 18

True or False: Cholera is common in Australia.

Answer 18

False

Most cases are acquired overseas; local acquisition is rare.

Question 19

Fill in the blank: Cholera is endemic to much of _______ and _______ , linked to inadequate WASH.

Answer 19

Africa, Asia

Question 20

What is the case definition for cholera?

Answer 20

Confirmed only by isolation

Question 21

T / F: cholero is mandatorily reportable to the WHO

Answer 21

True

Question 22

What happens if a cholera case travels to a non-endemic country?

Answer 22

Commonwealth DH will notify relevant health authorities

Question 23

T / F: cholera is subject to Australian quarantine

Answer 23

True