Travel Medicine Christopher Sanford, MD, MPH, DTM&H Acting Asst. Professor, Dept. of Family Med. Clinical Asst. Professor, Dept. of Global Health University of Washington Seattle, Washington, USA November 2010
Overview of pre-travel encounter: • 1) Intake questions: itinerary, medical history incl. immunizations, etc. • 2) Advised immunizations • 3) Malaria: PPMs, medication. • 4) Travelers’ diarrhea: diet, self-tx med • 5) Everything else: urban medicine: cars, smog, etc.; 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 • Review of past immunizations
Immunizations • Advised recommendations: • Routine • Required • Recommended
Immunizations (cont.) • 1. Routine: • Tdap (tetanus + diphtheria +pertussis) • MMR • Influenza—seasonal • Hepatitis A • Hepatitis B • Polio • Varicella
Tdap • Give Tdap –start at age 11. • Then in 10 years pt gets usual Td. • Tdap is a once/life vaccine.
Table 2-20. Countries with endemic diphtheria [2010 CDC Yellow Book] • Africa: Algeria, Angola, Egypt, Niger, Nigeria, Sudan, and sub-Saharan countries • Americas: Bolivia, Brazil, Colombia, Dominican Republic, Ecuador,Haiti, and Paraguay • Asia/South Pacific: Afghanistan, Bangladesh, Bhutan, Burma (Myanmar), Cambodia,China, India, Indonesia, Laos, Malaysia, Mongolia, Nepal, Pakistan, Papua New Guinea, • Philippines, Thailand, and Vietnam • Middle East: Iran, Iraq, Saudi Arabia, Syria, Turkey, and Yemen • Europe: Albania, Russia, and countries of the former Soviet Union Pertussis: Risk for Travelers Pertussis remains endemic worldwide, even in areas with high vaccination rates.
MMR • 2 doses, at least 4 weeks apart • Those born prior to 1957 assumed to be immune. • Of the 127 U.S. residents with measles in 2008, 7 were vaccinated, 21 had unknown vaccination histories, and 99 were not vaccinated. Of the 99 cases in unvaccinated U.S. residents: 67% were among persons unvaccinated because of their personal or religious beliefs. • The majority were import-associated. http://www.cdc.gov/mmwr/PDF/wk/mm5754.pdf
Measles deaths in Africa • Measles deaths among children under five years old in Africa: • 2000: 733,000 • 2008: 118,000 (United Nations data)
Influenza • Important: international travelers develop influenza more often than do folks who stay at home. • In temperate regions in Southern Hemisphere (e.g., Australia) flu season is April-November • Near equator, influenza is year-round.
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. • Minimum age: 12 months. • Don’t give Ig to immunocompetent travelers over the age of one year. • Lifetime protection.
Hepatitis B • 3 doses: at time 0, 1, and 6 months. • A large proportion of travelers have risks. • Twinrix: hepatitis A + hepatitis B • Schedule: 0, 1, 6 months
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 • None in the Americas
Pakistan •  PakistanDate: Tue 13 Oct 2009Source: IRIN [edited]<http://www.irinnews.org/Report.aspx?ReportId=86560>Polio outbreak in Swat----------------------Health officials say 13 cases of polio have been confirmed in Pakistan's volatile Swat District over the past 4 months, mainly because vaccinators have been unable to access children there for more than a year. Fierce fighting between government troops and Taliban militants, which began in May , has displaced hundreds of thousands of people from Swat. Before the army campaign in the area which ended in July , militants had prevented access for anti-polio teams.
CDC Update Oct. 2010 Outbreak NoticePolio Outbreak in Tajikistan, Cases in Russia, Risk of Spread to other Central Asian Countries Updated: October 22, 2010
Varicella • Two doses of varicella-containing vaccine are now recommended for all susceptible persons older than one year without contraindications. The first dose should be administered at 12–15 months of age and the second dose at 4–6 years of age. • The minimum interval for children younger than 13 years is 3 months. The ACIP now recommends that all others at least 13 years of age without evidence of immunity be vaccinated with two doses of varicella vaccine at an interval of 4–8 weeks • In temperate climates, varicella tends to be a childhood disease, with peak incidence during late winter and early spring. In tropical climates, infection tends to occur at older ages, resulting in higher susceptibility among adults than in temperate climates. http://wwwnc.cdc.gov/travel/yellowbook/2010/chapter-2/varicella.aspx
Immunizations (cont.) • 2. Required: a short list. • Yellow fever: • tropical Africa • tropical South America • [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. • Booster doses required at ten year intervals.
Meningococcal: • Required for Hajj (Muslim pilgrimage to Mecca) • Must be tetravalent • All meningococcal meningitis vaccine given in the US is tetravalent • Recommended for high risk travelers • Meningitis belt of sub-Saharan Africa • Crowded living conditions, e.g. dorm
2009-2010: 2nd and 3rd required Hajj vaccines: seasonal and pandemic influenza • Ministry of Health of Saudi Arabia states: • Seasonal influenza vaccine required • Pandemic (H1N1) flu required “if such vaccination is universally available” • http://wwwnc.cdc.gov/travel/content/in-the-news/saudi-arabia-hajj-2009.aspx
“meningitis belt”—the Sahel
Immunizations (cont.) • 3. Recommended • Typhoid fever • Consider: rabies • Consider: Japanese encephalitis • Cholera: No. Rabies avoidance: never hold hands with a gorilla.
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 • Older: JE-VAX. Three doses: d. 0, 7, 30. • New: Ixiaro. Two doses, d. 0 & 28. For 17 y.o. and older. FDA approved March 2009.
Live vaccines • TOY MMR BSVI • (oral typhoid, OPV, yellow fever, measles, mumps, rubella, BCG, smallpox, varicella, influenza [intranasal]) • Avoid in travelers with immunocompromise, pregnancy. • Safe to give in HIV-pos. travelers with CD4 counts over 400 • (or over 200, or over 500—authorities differ) • (except BCG—never give BCG to an HIV-positive person regardless of CD4 count)
Malaria • Protozoan organism, vector is Anopheles mosquito. • Illness characterized by high fevers, sweats, chills. • P. falciparum is the most prevalent species worldwide; associated with significant mortality. • There are approx. 100 countries in which malaria is endemic.
PPMs (personal protection measures) = BAM (bug avoidance measures) • Personal protection measures are at least as important as medications. Also benefit for diseases other than malaria, e.g. dengue fever.) • DEET (20-35% not 100%) or picaridin (20%, not 6-9%) to exposed skin. • Permethrin to clothes, once every two weeks. • Bed net, preferably impregnated with permethrin • Long sleeves/pants
Malaria: medications • Chloroquine still effective in only a handful of countries. • 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. 16-20 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.) • Contraindications (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. ~US $8.00/tablet • 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.
Travelers’ diarrhea • Very common. Up to 50% over 2-4 weeks. • A self-limited illness in most international travelers. • Duration can be shortened by antibiotics.
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
Study on 74K international travelers • Survey on TD [travelers’ diarrhea] among tourists to Goa (India), Mombasa (Kenya), Montego Bay (Jamaica), and Fortaleza (Brazil). • Rate of diarrhea in cautious, and adventurous eaters. • Steffen R, Tornieporth N, Costa Clemens SA, et al. Epidemiology of travelers' diarrhea: details of a global survey. J Travel Med 2004;11(4):231-238.
“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… have shown similar results.” • 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.
No evidence of benefit • More expensive hotel or restaurant • Garlic • Lemon juice
Traditional wisdom: The bad list: → 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 microorganisms that can cause diarrhea.
Traditional wisdom: Dietary strategy to reduce risk of travelers’ diarrhea • The (relatively) safe list:→ Boiled anything. → Bottled anything—water, beer, pop (if sealed). → Dry foods, e.g. bread. → Packaged foods. → Well-cooked food. → Fruits which require peeling (oranges, bananas)
Two strategies I don’t recommend: • Prophylactic antibiotics • Cipro 500 mg qd, not to exceed 3 weeks, reduces risk of TD • 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