Travel Medicine Flashcards
Big three issues for travel medicine
1) Vaccine use in travel
2) Management of traveler’s diarrhea
3) Prevention of malaria
When to schedule pretravel clinic visit
Pretravel advice should be sought 4–6 weeks before departure to best prepare the traveler and ensure that appropriate vaccinations can be provided
Key counseling points for travel medicine visit
All travelers should be advised on vaccine-preventable illnesses/required immunizations, avoidance of insects, malaria chemoprophylaxis if visiting an area of risk, prevention and self-treatment of TD, and responsible behaviors (e.g., wearing seatbelts, helmets on motorcycles).
Altitude sickness prevention and management
Altitude sickness should also be discussed if high-altitude destinations are planned or patients have a history of altitude sickness. a. Prophylaxis with acetazolamide is usually effective and can hasten recovery if symptoms develop. b. Dexamethasone may also be used, but is more commonly considered as an adjunct in descent.
Percentage of malaria and typhoid in the US from visiting friends and relatives
About 50% of malaria imported into the United States in 1999–2003 occurred in VFR travelers. c. Around 75% of imported typhoid cases also occurred in this population.
Most serious infection in returning travelers
Malaria, specifically Plasmodium falciparum malaria, is the most serious infection in returning travelers and remains the most common cause of death.
Early fever in returning travelers
If fever develops beyond 21 days, dengue, rickettsial infections, Zika virus, and viral hemorrhagic fevers are less likely.
Malaria incubation period
Incubation period is often 1–4 weeks but can be longer, depending on the patient’s immune status, dos- ing of chemoprophylaxis, and infecting Plasmodium strain. Febrile patients presenting before 7 days are unlikely to be infected unless exposed to infected mosquitoes before travel.
Rabies incubation period
20-60 days (can be months to years)
Incubation period: anthrax
Cutaneous: 1 day; Pulmonary: 1-7 days
Incubation period: plague
Bubonic plague: 2-6 days
Pneumonic plague: 1-3 days
DEET cutoffs by age
For travelers with children and/or infants (older than 2 months) DEET is considered safe, but the concentration should not exceed 30%. c. DEET should not be used in infants younger than 2 months. 4. An alternative to DEET is picaridin,
Purposes of thick and thin smears for malaria
Thick smears screen large amounts of blood for the presence of parasites.
health department. 5. Thin smears are used to determine the infecting Plasmodium spp. with significant implications for pharmacotherapy.
Most important diagnosis for returning traveler
Any traveler presenting with fever and a history of travel to a malaria-endemic area in the past 3 months should be considered to have malaria until ruled out.
Malaria chemoprophylaxis regimens starting 1-3 weeks before travel
Chloroquine & mefloquine; continue 4 weeks after return
Malaria ppx regimes, start 1-2 days before travel
Atovaquone/proguanil - continue 1 week after
Primaquine - continue 1 week after
Doxycycline - continue 4 week after
Treatment of uncomplicated malaria
Artemether/lumefantrine x3 days Atovaquone/proguanil x 3 days Hydroxychloroquine x48 hours Chloroquine x48 hours mefloquine x2 doses Quinine + (doxycycline or tetracycline or clindamycin) x7 days
Incubation periods for travelers diarrhea
Incubation period is typically up to 3 days, but can be within hours for bacterial and viral pathogens versus some protozoal pathogens, which may take 1–2 weeks and is less likely to present early in travel.
Average duration of untreated travelers diarrhea
Average duration of untreated diarrhea is 4–5 days, but is pathogen-dependent. Comparatively, proto- zoal pathogens may cause diarrhea for weeks to months if left untreated.
Etiology of travelers diarrhea
Disease etiology is predominantly secondary to bacterial enteropathogens (up to 85%); however, viruses and protozoa/parasites should also be considered causative pathogen
Role of prophylaxis in travelers diarrhea
Antimicrobial prophylaxis is not currently endorsed by the IDSA guidelines and should only be used in travelers for whom development of diarrhea would be more likely to lead to complications.
considered for antimicrobial prophylaxis: a. Patients who should avoid dehydration b. History of stroke/transient ischemic attack c. Insulin-dependent diabetes mellitus d. Chronic renal failure e. Patients with possibility of complex diarrheal episodes i. Inflammatory bowel disease ii. AIDS iii. Patients with ileostomies/colostomies
Travelers diarrhea prophylaxis medications and duration
Ppx regimens:
Bismuth 2 tabs q6h
Cipro qd-bid
Rifaximin qd-bid ac
If indicated, prophylactic antimicrobials should be taken for the duration of the trip, but limited to no longer than 3 weeks.
Activity of antimicrobials vs TD pathogens
Fluoroquinolones are effective against most bacterial pathogens except for C. jejuni.
Rifaximin is not considered active against mucosally invasive pathogens such as Shigella, Salmonella, or Campylobacter.
Azithromycin is a useful alternative where Campylobacter spp. are more common
Zika virus sexual transmission
Sexual transmission from infected travelers to non-traveler partners has occurred within 20 days of first sexual contact in all transmissions studied to date.
In males, the CDC recommends the use of condoms and/or abstaining from sexual activity for at least 6 months after exposure or travel to an area of risk because of documented viral persistence in semen.
In females, the CDC recommends 8 weeks of consistent condom use or abstinence after exposure or travel to an area of risk.
