Travel Health in the Developing World Christopher Sanford, MD, MPH, DTM&H Clinical Asst. Professor, Dept. of Family Med. Co-Director, Travel Clinic, Hall Care Center University of Washington Seattle, Washington, USA September, 2009 Amazon River, Peru
Overview of pre-travel encounter: • 1) Intake questions: Itinerary, activities. Past medical history incl. immunizations. • 2) Advised immunizations. • 3) Malaria: PPMs, medication. • 4) Travelers’ diarrhea: diet, carry along med. • 5) Urban medicine: cars, smog, etc. • 6) Resources.
Intake questions • Where to • For how long • For what purpose • Staying in what kind of place • Guided or not • Previous developing world travel or not
Intake questions • Past medical history— • Allergies • History of antimalarial use if any • Medications • Medical problems • History of depression, anxiety • LMP, birth control • None of antimalarials proven safe in pregnancy
Immunizations • Review of past immunizations • Advised recommendations: • Routine • Required • Recommended
Immunizations (cont.) • 1. Routine: • Td (tetanus + diphtheria)—or Tdap within 10 years • MMR • Influenza • Hepatitis B • Polio
Tdap • Give Tdap if it’s been over 10 years since Td. • Then in 10 years pt gets usual Td • Tdap is a once/life vaccine • CDC site: “Adults aged 19-64 years who have not previously received Tdap should receive a single dose of Tdap if their last dose of tetanus toxoid-containing vaccine was administered more than 10 years prior”
MMR • 2 doses, at least 4 weeks apart
Influenza • Important • International travelers develop influenza more often than do folks who stay at home. • Transmission is year-round at the equator.
Hepatitis B • 3 doses: at time 0, 1, and 6 months. • A large proportion of travelers have risks.
Polio • One dose as an adult on top of the usual pediatric series. • If going to area with polio: • Now in about 25 countries in Africa • And the Indian subcontinent: India, Pakistan, Bangladesh
Immunizations (cont.) • 2. Required: a short list. • Yellow fever: • tropical Africa • tropical South America • [none in Asia]
Yellow fever Distribution [None in Asia]
Yellow fever • Required for entry into • In South America: • Bolivia, and French Guiana
Yellow fever • Required for entry into: • Africa: • Angola, Benin, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Congo, Cote de I’voire, Democratic Republic of Congo, Gabon, Ghana, Liberia, Mali, Mauritania (for stay over 2 weeks), Niger, Rwanda, Sao Tome and Principe, Sierra Leone, and Togo. • Not required for return to U.S. regardless of previous destination.
Meningococcal: • Required for Hajj (Muslim pilgrimage to Mecca) • Recommended for high risk travelers • Meningitis belt of sub-Saharan Africa • Crowded living conditions, e.g. dorm
Immunizations (cont.) • 3. Recommended • Everyone: Hepatitis A • Typhoid fever • Consider: rabies • Consider: Japanese encephalitis • Cholera: No. Rabies avoidance: never hold hands with a gorilla.
Hepatitis A • Appropriate for every nation in the developing world. • “The most frequent vaccine-preventable disease in international travelers.” • 2 doses, at least 6 months apart. • Don’t give Ig to immunocompetent travelers over the age of one year. • Lifetime protection.
Typhoid fever • Present throughout developing world. • Risk in increased in long-stay travelers, and those off the beaten path. • Either oral (good for 5 years). • Minimum age 6 years. 4 pills. One pill every other day. • Or via injection (good for 2 years). • Minimum age 2 years. One dose.
Rabies • Three doses, over 28 days. • Expensive. • Rabies rare in travelers. • Consider for prolonged stay, backpackers, spelunkers, others with significant risk. • Pre-exposure series does not remove need for immediate post-exposure treatment.
Japanese encephalitis • Spread by mosquitoes, present throughout South and Southeast Asia. • Expensive • Rare--rural only. Associated with rice and pig farming. • Vaccine: 3 doses over 30 d. • Adverse effects: can be delayed. Finish series at least ten days prior to departure.
Malaria • Personal protection measures are more important than medications. • DEET to skin (20-35% not 100%) • Permethrin to clothes, every 2 weeks. • Bednet, preferably impregnated with permethrin • Long sleeves/pants • Also benefit for diseases other than malaria, (e.g. dengue.)
Malaria: medications • There are approx. 100 countries with malaria. Chloroquine still effective in only a handful. • Mexico, and Central America to west of Panama Canal • Island of Hispaniola (Dominican Republic and Haiti) • North Africa (prophylaxis not recommended)
chloroquine-sensitive areas • chloroquine or Plaquenil once/week • Schedule: start one week before entry, take once/week while in malaria country, take for four weeks after exit. • In US, Plaquenil is one-fifth cost of chloroquine • Dose • chloroquine: 300 mg base = 500 mg salt once/week • Plaquenil: 310 mg base = 400 mg salt once/week
Chloroquine-resistant countries • 3 options: • doxycycline • mefloquine (Larium) • atovaquone/proguanil (Malarone)
doxycycline Dose: 100 mg once/day. Start one day prior to entry to malaria area, take once/day while, continue for 28 days after leaving malaria area. Cheap. Approx. 16 cents/pill. Side effects: photosensitivity. Less than one percent. esophageal erosion. Don’t swallow tablet “dry”
Mefloquine (Larium) • 250 mg (salt) once/week. Start one week prior to entry into malaria area, continue once/week while there, continue once/week for four weeks after leaving malaria area. • Price: intermediate. • Contraindications: people with any type of psychiatric history ever (e.g., depression, anxiety) should not take this.
Mefloquine (Larium) (cont.) • Side effects (cont.) • No one should take this who: • Has had cardiac conduction defects • Seizures (aside from uncomplicated febrile seizures in childhood) • Doesn’t want to take it.
Malarone (atovaquone and proguanil) • Expensive. • Once/day: begin one day prior to entry into malaria area; take one/day while there, continue once/day for 7 days after exiting malaria area. • Only one adult strength: Each tablet: 250 mg atovaquone + 100 mg proguanil • Side effects: lowest rate of the 3 drugs for chloroquine-resistant malaria. • Rash, GI upset, mood changes.
What about carry-along standby self-treatment, instead of prophylaxis? My vote: no. You can’t diagnosis malaria clinically. Diagnosis is only possible via laboratory exam (thick and thin smears of blood). Card diagnostic test is not yet ready for prime time. May be an option in the future.
An exception • Consider carry along/standby medication for geographically remote traveler. • E.g. Malarone if not taking it for prophylaxis.
Travelers’ diarrhea • A self-limited illness in most international travelers. • Duration can be shortened by antibiotics. • Very common. Up to 50% over 2-4 weeks.
Sign with unknown significance, Korea
Synonyms • Aztec two-step • Delhi belly • Hong Kong dog • Montezuma’s revenge • Rangoon runs • Turista • etc., etc., etc. (DuPont & Steffen [see bibliography] lists 32 synonyms)
Cause of travelers’ diarrhea • Usually bacterial, usually ETEC (enterotoxigenic E. coli). Relatively recently described EAEC (entero-adherent E. coli) also common • More rare causes: • Other bacteria: Shigella, Salmonella, Campylobacter • Protozoan: Giardia • viral
Dietary strategy to reduce risk of travelers’ diarrhea • Not much evidence that eating practices reduce risk. • The (relatively) safe list:→ Dry foods, such as bread. • → Packaged foods. • → Well-cooked food. • → Bottled anything—water, beer, pop (if sealed). • → Boiled anything.
Steffen R, Tornieporth N, Costa Clemens SA, et al. Epidemiology of travelers' diarrhoea: details of a global survey. J Travel Med 2004;11(4):231-238. • “This study adds to a growing literature that conventional advice on avoidance of specific food and drink items seems to be ineffective in reducing risk.” • “Where one eats may be more important than what one eats.” • survey on TD [travelers’ diarrhea] among tourists to Goa (India), Mombasa (Kenya), Montego Bay (Jamaica), and Fortaleza (Brazil). • 73,630 travelers (15,631 from Goa, 15,180 from Mombasa, 30,369 from Montego Bay, and 12,449 from Fortaleza)
“there were no differences in [prohibited] food scores between those who did and did not have TD [travelers’ diarrhea]” • “Cumulatively, a number of other studies over the past 20 years that were reviewed in a plenary lecture at the ISTM Conference in New York in 2003 have shown similar results.”
The bad list: things to avoid: • →Food from street stands (street vendors). • →Salads. →Raw food, such as sushi.→Buffets, even at nice hotels or restaurants, in which food sits out for several hours. • →Tap water. • →Ice. Freezing doesn’t kill most of the germs that can give you the trots.
Two strategies I don’t recommend: • Prophylactic antibiotics • These can have side effects in and of themselves • Pepto-Bismol • It works: you chew 2 tablets, four times/day, for the whole trip. • Benefit: 50-65% reduction in travelers’ diarrhea • Drawbacks: black tongue, weird black poop
Stand-by medication • Taken only if symptoms develop • For most of the world: a fluoroquinolone (e.g., ciprofloxacin, levofloxacin) • For Southeast Asia*: azithromycin, one dose only. • Duration without treatment: 3-5 days. • Duration with treatment: 12-24 hours. • *Brunei, Burma (Myanmar), Cambodia, East Timor, Indonesia, Laos, Malaysia, Philippines, Singapore, Thailand, Vietnam
Travelers’ diarrhea caveats: • Take self-treatment medication only for “normal” diarrhea • If blood in stool, • Or fever, • Or significant abdominal pain, • Or if not better 2 days after starting antibiotics— See a doc!
2nd self-treatment drug • An antimotility drug: e.g. loperamide (Imodium AD) • 2 at onset of symptoms, then 1 after each loose BM not to exceed six/day.
TD carry-along med algorithm • Pt feels good Takes nothing • Mild diarrhea Imodium-AD only • Watery diarrhea Imodium-AD + Cipro • Sick See doc • Blood in stool • Fever • Significant abd. pain
Special oral rehydration solution -Only needed at extremes of age. -No need to “rest” the gut during recovery.