Transcript Travelers’ Health

Travelers’ Health
April 2004
Dr. Tim Cook
USEFUL WEBSITES
Health Canada
http://www.hc-sc.gc.ca/pphb-dgspsp/tmp-pmv/index.html
CDC Travelers' Health
http://www.cdc.gov/travel/
Morbidity and Mortality Weekly Report
http://www.cdc.gov.mmwr/
CASE
Healthy recently graduated physician
joins MSF and immediately deploys to
CAR (Central African Republic)
What health risk mitigation information
should he be given?
Vaccines?
Rx?
INFECTIOUS
VECTOR-BORNE DISEASE
MALARIA
DENGUE FEVER
NEMATODES
• FILARIASIS, ONCHOCERCIASIS, LOAIASIS
TRYPANOSOMIASIS
YELLOW FEVER
RICKETTSIAE (Ticke-borne)
(JAPANESE ENCEPHALITIS – not in Africa)
PPM
(PERSONAL PROTECTION MEASURES)
DEET
28% lasts 6-8 hours
6% lasts < 1 hr
95% no longer available
Slow-release better (Ultrathon, Sawyer’s)
LONG SLEEVES, PANTS
BEDNETS (Permethrin-impregnated)
MALARIA
CHEMOPROPHYLAXIS
MALARONE (Atovaquone + Proguanil)
Daily, day before until 1 wk after departing
S/E Mild GI, HeadAches
Safe in aircrew, drivers etc.
EXPENSIVE ($5/DAY)
MEFLOQUINE
DOXYCYCLINE
PRIMAQUINE
DENGUE
Throughout tropics
Day biting Aedes Egypti mosquito
therefore use DEET night AND day
No vaccine (yet!)
PPM only
INFECTIOUS
HUMAN-BORNE
TB – two step Mantoux recommended
STDs incl Hep B / HIV
Influenza
• yr round in tropics
Meningococcus
INFECTIOUS
FOOD / WATER-BORNE
Typhoid (salmonella)
• Non-typhoid salmonella
ETEC – commonest cause of travelers’ diarrhea
• Toxin = secretory diarrhea
Cholera – similar toxin as ETEC
Other bacteria (shigella / campylobacter / yersinia
Virus - Hepatitis A (Norwalk, Rota) less common
Parasites (E.Histolytica, Cyclospora ,
Cryptosporidia) <3% of TD but more common in
persistent diarrhea
Schistosomiasis – DON’T SWIM IN FRESHWATER
INFECTIOUS
ZOONOSES (Animal – borne)
Q fever (rickettsia)
Brucellosis
Tularemia
Rabies
Many others ALL RARE
NON-INFECTIOUS
FLORA
FAUNA …. AVOID!
ACCLIMATIZATION
ALTITUDE SICKNESS (hikes Kilimanjaro!)
Climb high, sleep low, go slow
Acetazolamide (Diamox) 250 mg OD
• Carbonated beverages taste flat!
• Does not prevent HAPE, HACE – emergent descent or
pressure bag, O2, steroids, nifedipine, supportive care
NEEDLE STICK INJURY (Bring triple therapy?)
VACCINES?
ROUTINE
RECOMMENDED
REQUIRED
ROUTINE VACCINES
TdP
MMR
RECOMMENDED
HEPATITIS A – 2 doses, > 10 yrs
HEPATITIS B – 3 doses, > 10 yrs
TWINRIX – both A & B, 3 doses
INFLUENZA – annually / pre-travel
TYPHOID
Typhum Vi – 1 dose, lasts 3 yrs, 75% effective
Vivotif – oral, 4 doses, lasts 5 yrs, similar efficacy
RABIES
MENINGOCOCCUS
DUKORAL
New (Aug 2003)
Oral vaccine against toxin of ETEC and
cholera
2 doses 1 wk apart
~75% effective
Only lasts 3 months
$$ (75)
REQUIRED
YELLOW FEVER
MENINGOCOCCUS (only req’d for
participation in the Hajj, travel to
Mecca)
YELLOW FEVER
monkey zoonosis transmitted to humans by
mosquitoes
Classic (but more severe than ususal)
clinical manifestations:
Fever, headache, abdo pain and vomiting;
Short period of improvement;
Then liver and kidney failure, shock +/- bleeding
YELLOW FEVER CONT’D
certain countries require vaccination for entry
live attenuated virus; may be safe in
asymptomatic HIV; patients should be given
choice
single dose
if egg anaphylaxis, two options:
Intradermal skin testing with the vaccine
Letter documenting contraindication --> waiver
from embassy
TYPHOID
most important in Indian subcontinent
use in travellers going outside of tourist areas or
to places with known typhoid epidemics
capsular polysaccharide vaccine; single injection
MENINGOCOCCUS
frequent epidemics in sub-Saharan Africa (belt
across the middle of the continent from Guinea to
Ethiopia); patient at risk if there >3 weeks or not
staying in hotels
risk in pilgrims going to Mecca for the hajj
single dose to these travellers 10 - 14 days pretravel
HEPATITIS A
fecal to oral
prevalent in MANY countries; all of Africa and South
America, SE Asia
0.3% per month risk of infection in developing countries if
patient is careful where they eat
vaccine is inactivated virus
safe, very effective
protection after four weeks
booster in 6 - 12 months (depending on formulation)
can use Immune Globulin for prophylaxis in patients who
can’t be vaccinated
NOTE: other major indication for HAV vaccine is all patients
with chronic liver disease
Japanese encephalitis
mosquito-borne arbovirus
important in late summer -- autumn in much of
East Asia except urban China/Japan or Singapore
consider in patients going in Summer/Fall, esp. to
rural areas or for a prolonged stay in urban areas
three doses over the course of a month
Measles
if born after 1970, with no proof of vaccination, if
travelling to endemic area
PRESCRIPTIONS
ANTI-MALARIAL
STANDBY FOR TRAVELERS’ DIARRHEA
Azithromycin – 1 g all at once
Cipro – 1 g at once
Acetazolamide
CASE 2
2 days after returning to Canada the
physician calls you complaining that he
has a fever (38.5) and some diarrhea?
What are your recommendations?
FEVER IN RETURNING
TRAVELER
MALARIA, MALARIA, MALARIA
DENGUE
TYPHOID
“DEVELOPED WORLD DISEASES”
INFLUENZA, PNEUMONIA, UTI etc
WHAT TO DO?
Consider it a medical emergency!
CBC (anemia, thrombocytopenia in malaria
and dengue)
Thick and thin smears (malaria)
Blood cultures (typhoid)
LDH (hemolysis - malaria)
Stool cultures
Treat as P.Falciparum until proven otherwise!