W. David Colby, MSc, MD, FRCPC Director, Travel Medicine Chatham-Kent & Middlesex-London Health Units Associate Professor Medicine & Microbiology/

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1 Malaria to Montezuma: Navigating the Waters of Travel Health UWO Senior Alumni January 30, 2007 W. David Colby, MSc, MD, FRCPC Director, Travel Medicine Chatham-Kent & Middlesex-London Health Units Associate Professor Medicine & Microbiology/ Immunology,

2 What is Travel Medicine? It s more than Don t drink the water An interdisciplinary specialty concerned with the prevention and management of health problems associated with travel. Not yet a medical specialty in Canada International Society of Travel

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4 Health Problems Associated with Travel 100,000 travelers to developing world for one month: 50,000 will have some sort of health problem 8,000 will consult a physician 5,000 will be confined to bed

5 Health Problems Associated with Travel (cont.) 1,100 will be unable to work (abroad or after returning home) 300 will have to be hospitalized (abroad or on returning home) 50 will require air evacuation to another country One traveler will die

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7 Vaccine Preventable Diseases Smallpox Tetanus Diphtheria Polio Measles Mumps Rubella Pertussis Chickenpox Haemophilus influenzae b Neisseria meningitidis A, C, Y, W-135 Hepatitis B Hepatitis A Typhoid Fever Japanese Encephalitis Rabies Tick-borne Encephalitis Yellow fever Cholera Traveler s Diarrhoea

8 Cholera

9 Site of Broad Street Pump, Broadwick & Poland, Soho

10 Cholera Vibrio cholerae Gram-negative curved rod with single polar flagellum mainly water borne non-invasive infection of the intestine major virulence factor is a secreted toxin

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15 Hepatitis A The incidence rate of symptomatic Hepatitis A for a one month journey from an industrialized country to a developing country is 1 in 300 for the normal non-immune traveler. This applies also to tourists staying in renowned hotels. Dr Robert Steffen University of

16 Hepatitis A Transmitted by contaminated food and water, also person to person Usually self-limited Prevention via food and water precautions and vaccination

17 Jaundice

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20 Fulminant Hepatitis A Incidence is age-dependent: <14 years 0.1% years 0.4% 40 + years 1.1% Rx: liver transplantation

21 Hepatitis A Vaccines Four brands of vaccine available in Canada, including Hepatitis A/B combination All highly efficacious and well tolerated, some differences in rapidity of onset of protection Long term protection with two doses Residence years in a

22 TwinRix in Travel Medicine Hepatitis A and B have completely different epidemiologies Hepatitis B is not a travel disease Need 2 doses of TwinRix for Hepatitis A protection

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24 Typhoid Fever Salmonella typhi Transmitted by food and water Adventure travel, off the beaten track, visiting friends and relatives increases risk Highest incidence in Indian subcontinent, Peru, Africa (except South Africa)

25 Salmonella typhi

26 Typhoid Fever Vaccines Injectable: highly purified Vi antigen, well tolerated. Protection 3 years. Live oral: protection 7 years, but reliable formulation unavailable. And

27 ViVAXIM Hepatitis A and Typhoid Fever combination vaccine These diseases have the same epidemiology Contains full hepatitis A dose (unlike TwinRix) Great for needle phobics

28 Meningococcal Meningitis Neisseria meningitidis Respiratory transmission, particularly under crowded conditions Seasonal in sub-saharan Africa (Dec-June highest) Saudi Arabia during the Hajj

29 Meningococcal Vaccines The conjugate vaccines currently used in routine childhood vaccine programs (NeissVac C TM, Menjugate TM ) cover serogroup C only Menomune is a polysaccharide vaccine covering A, C, Y and W-135 Poor efficacy in children < two, not used for routine childhood immunization in Canada Menactra TM is a conjugate vaccine that covers A, C, Y, and W-135 -Suitable for travel and high-risk populations Sanofi pasteur, Product Monograph MENACTRA TM. Toronto ON: sanofi pasteur Limited, 2006:1-43. Diaz R. Invasive meningococcal disease in Ontario: January 1, 2002 to December 31, Public Health and Epidemiology Report Ontario (PHERO). 2004;15(1):1-7. Granoff DM, et al. Meningococcal Vaccines. In: Plotkin SA and Orenstein W, ed. Vaccines. 4th ed. Philadelphia, PA: WB Saunders Co; 2004: In: Plotkin SA and Orenstein W, editors. Vaccines. 4th ed. Philadelphia, PA: WB Saunders Co; 2004:

30 Meningitis Belt of Africa

31 Traveler s Diarrhoea

32 Travelers Diarrhoea Canada: Beaver fever Mexico: Aztec two step, Montezuma s revenge, Turista South America: Santiago shuffle Middle East: Turkey trots India: Delhi belli Africa: Seeping slickness Russia: The Trotskys

33 Diarrhoeal disease A leading global health problem o Poor data o Estimated 3 5 billion episodes of diarrhoea annually in developing countries o Approximately 5 million deaths annually o About half caused by enterotoxic enteropathies: Vibrio cholerae - most severe

34 Travelers Diarrhoea The problem Most common medical problem affecting travelers to the developing world Up to 70% of travelers will have at least one episode per two week stay Risk depends on destination (high in Latin America, diarrhoea central ) and diet 40% forced to alter activities/change itinerary 25% confined for at least 1 day 3% get persistent gastrointestinal problems

35 Etiology of Travelers Diarrhoea 1. Bacterial 85% 2. Parasitic* 5-15% 3. Viral < 5% *protozoal or helminthic

36 Transmission of ETEC Fecal oral route Food, and to a lesser degree, water are the main sources Major cause of disease in children in developing countries

37 Prevention of Travelers Diarrhoea 1. Food and water precautions: Boil it, cook it, peel it or forget it Easy to remember, impossible to do! 2. Vaccinate: Dukoral is the first new TM vaccine for travelers in many years and is now the #1 selling vaccine at the MLHU Travel Clinic

38 Rx of Travelers Diarrhoea Oral rehydration: always a good idea Bismuth subsalicate: effective, cheap, also settles stomach Antimotility agents (loperamide): use with caution! Sepsis, toxic megacolon Antibiotics (fluoroquinolone X 3 d): useless in Thailand due to resistance, contraindicated in VTEC (EHEC) Probiotics (L. acidophilus)??

39 Malaria If we take as our standard of importance the greatest harm to the greatest number, then there is no question that malaria is the most important of all infectious diseases. Burnett Sir MacFarlane

40 Malaria Risk in > 100 countries 300 million cases annually Marked increase in drug resistance Deaths from malaria each year = deaths from AIDS over 10 years!

41 Anopheles spp.

42 No consent for blood taking!

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44 Merozoite Release

45 Prevention of Malaria Personal Protective measures: repellent, bed net, screened or air conditioned quarters dusk to dawn Antimalarial drugs

46 Local Environmental Risks Motor Vehicle accidents Urban violence Barefoot walking Biting insects Rabid animals Freshwater swimming Food and water Sexual contacts Hazardous landscape Laundry

47 No vaccine (personal protection Dengue Primarily transmitted in urban areas Indoor, day-biting mosquitoes Usually self-limited, flu-like illness Rare: dengue haemorrhagic fever, dengue shock syndrome

48 F.E.D.

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50 Schistosomoasis?

51 Cutaneous Larva Migrans: Ancylostoma brasiliense

52 The Top Ten Obnoxious Creatures in the Universe 1. Candirú (Vandellia spp.) 2. Giant desert centipede 3. Somalian camel spider 4. African blood sucking moth 5. Eye moth 6. Dracunculus mediensis (Guinea worm) 7. Loa loa (Eye worm) 8. Black mamba 9. Naeglaria fowleri (brain amoeba) 10. Belinda Stronach (Politicus betraicus)

53 Centipedes Giant desert centipede of SW US Very aggressive

54 Candirú (Vandellia spp.)

55 Challenges in Travel Medicine OHIP delisting July 1, 1998 Competition by OHIP fraud Partial service providers Failure of private health plans to cover Travel Medicine, including UWO Faculty and Student plans Lack of support from the travel industry