Traveller's Diarrhea Flashcards
What is the incubation period of traveller’s diarrhea?
2 weeks
Incidence rate of TD within the initial 2 weeks of stay determines the risk of TD
What are the risk categories for traveller’s diarrhea?
High >20%
Intermediate 8-20%
Low <8%
TD is usually ____-__________ even without therapy. It usually lasts <___hrs.
Self-limiting
<48 hrs
Does an episode of TD protect against future attacks?
No, you can get multiple in a single trip
What are the different severities of traveller’s diarrhea?
Mild= tolerable, no distress, does not interfere with plans
Moderate= distressing, interferes with plans
Severe= incapacitating, completely stops plans
Dysentery= grossly bloody stools (automatically severe)
Persistent= ≥2 weeks
What are the bacterial pathogens involved in TD?
E. coli, campylobacter, salmonella, shigella
What are virus pathogens?
Norovirus, astrovirus, rotavirus
What are protozoa pathogens involved in TD?
Giardia, cryptosporidium
What are symptoms that indicate more severe infection and warrant evaluation?
High fever, mucoid stools, persisting >2 weeks after return
A helpful non-pharm tip is:
____it, ____it, ____it, or forget it.
Boil, cook, peel
Are carbonated drinks safe for traveller’s diarrhea prevention?
Yes
Are alcoholic drinks safe for traveller’s diarrhea prevention?
No
What are four ways that water can be sterilized for drinking?
Heat, filtration, chemical, UV
How do you sterilize water by heat?
Boil for 1 min
How do you sterilize water by filtration?
Apply filter which should be followed by chemical disinfection if possible.
How do you sterilize water by chemical?
Chlorine or iodine
For individuals travelling to high rates of TD, what drug class should we consider reassessing the need for?
PPIs and H2RAs
What are four agents that may be used for prevention of TD?
- Bismuth Subsalicylate (Pepto)
- Antibiotics
- Vaccines
- Probiotics
How has bismuth subsalicylate been postulated to help prevent TD?
- Anti-bacterial
- Anti-secretory
- Anti-inflammatory
What is a common side effect of bismuth subsalicylate?
Black stool which can be confused with melena
When should we avoid bismuth subsalicylate?
- Patients taking anticoagulants or salicylates
- Allergic to salicylates like ASA
- Young children (risk of bismuth encephalopathy). Not for <2
Are antibiotics routinely recommended for TD?
No. It increases the risk of adverse events, C. difficile, and antimicrobial resistance
Who would typically get antibiotics for TD?
- High risk of TD or complications (immunocompromised, comorbid disease)
- Critical travel (diplomatic missions)
- Diarrhea every time they travel
How long should we limit antibiotic prophylaxis for?
<3 weeks
Which antibiotics are typically used for TD prophylaxis?
Fluoroquinolones
- ciprofloxacin
- levofloxacin
- norfloxacin
Azithromycin
Rifaximin (not available in Canada)
Which antibiotics are not recommended for TD prevention anymore due to bacterial resistance?
Doxycycline and Septra
When can we not use the fluoroquinolones for TD prevention?
Southeast Asia
Ex: Thailand, India, Nepal, Indonesia
Azithromycin would be the preferred alternative
What’s the name of the vaccine for TD? How does it work?
Dukoral
- contains non-toxic B subunit of cholera toxin which is very similar to toxin of E.coli
Is the cholera vaccine routinely recommended?
No. Considered in short-term travellers at high risk of health complications or serious inconveniences due to TD.
There is limited evidence for use of probiotics in TD, but which two strains seem to provide benefit?
Lactobacillus rhamnosus GG, Saccharomyces boulardii
If patient has mild diarrhea, what diet should they follow?
Banana
Rice
Apple sauce
Toast
-Hydrate (electrolytes)
-limit fatty or oily foods
-avoid natural laxatives (caffeine, alcohol, excessive fruit
-limit dietary fibre as it can worsen bloating or cramping
What are four agents that may be used for treatment of TD?
- Oral rehydration therapy
- Bismuth Subsalicylate
- Loperamide
- Antibiotics
When is ORT recommended for treatment of TD?
Cornerstone therapy (especially for infants, pregnant women, and frail elderly)
If ORT is not available, what’s an emergency substitute?
1L of safe water+ 1/2 tsp of salt+ 6 tsp of sugar
How does bismuth subsalicylate help treat TD?
Reduce duration and frequency of diarrhea
When is antimotility agents like loperamide used in TD?
mild to moderate diarrhea
When should loperamide be avoided?
- children <2
- bloody diarrhea
- fever
When do antibiotics come into TD treatment?
Mild diarrhea is managed with ORT, loperamide and/or bismuth subsalicylate.
If these fail or more serious symptoms (blood, cramps, high fever) present, start antibiotics.
Which antibiotics are effective in treating TD?
- Fluoroquinolone for ETEC predominant areas like America and Africa
- Azithromycin for Asia (especially Thailand, Indonesia, Nepal, India, and Mexico)
- Rifaximin (not available in Canada)
- Septra no longer recommended
What class of antibiotic is not recommended in children?
fluoroquinolones
In children, what is the age requirement for loperamide?
Must be older than 2, and treatment should not exceed 2 days
In children, what is the age requirement for bismuth subsalicylate?
Must be older than 2 and caution in those younger than 12.
Is chemoprophylaxis recommended in pregnancy?
No
How do you treat TD in pregnancy?
ORT, loperamide, azithromycin
Avoid bismuth subsalicylate, fluoroquinolones, and iodine
Should breastfeeding be continued during travel?
Yes, safer for baby
How do you treat TD in breastfeeding?
ORT, loperamide, azithromycin
Avoid bismuth subsalicylate, fluoroquinolones, and iodine
Is it better to use antibiotics for prophylaxis or treatment?
Treatment
Mild TD usually resolves within ____ hours with loperamide, BSS, or fluids.
24 hours
If symptoms persist for >___ week after returning home, investigate for other causes.
2 weeks
A common cause is IBS. Other considerations include parasitic infection or antibiotic associated colitis.
If patient has fever or dysentery, seek medical attention if symptoms don’t improve within ___ hours despite therapy.
48 hours
What’s the treatment algorithm for traveller’s diarrhea?
Mild= loperamide and/or bismuth -> refer if longer than 2 weeks
Moderate= ORT, loperamide and/or antibiotic -> refer if longer than 2 weeks
Severe= ORT + antibiotics (+/- loperamide if not dysentery) -> refer if longer than 48 hrs after starting antibiotics
