Overview of Travel Medicine

Transcription

1 Content Overview of Travel Medicine Concept and Scope of Travel Medicine Pre-travel evaluation & Immunization for traveler Malaria prevention and prophylaxis Case studies returned travelers Watcharapong Piyaphanee MD, Board Int Med, CTH, Dip Trav Med, MFTM RCPS (Glasgow) Travel Medicine Research Unit Department of Clinical Tropical Medicine Faculty of Tropical Medicine, Mahidol University It s a small world! Travel in Human history We have always traveled throughout our history In the early era, people traveled because Seeking a new resource, new land Curiosity Escape from famine, outbreak, war Religion belief Trade Travel in Human history Number of International Travelers Today we travel because Relax and Leisure (Tourism) Business Academic purpose Visiting friends and relatives Escape from famine, poverty, political conflict Humanitarians/volunteer help etc Source: UNWTO,

2 Thai Travelers People travel as well as diseases In 2011, approx 5.4 millions Thais travel internationally Common destination for Thais ASEAN 3.3 millions (Malaysia, Laos, Singapore, etc) Asia 1 millions (China, Japan, Korea) Europe 500,000 Middle East 200,000 South Asia 112,000 Australia, USA, Africa Data from Ministry of Tourism and Sport Risk of Travel Risk of Infectious diseases Spreading of infectious diseases from one country to another Risk of exacerbation of existing diseases e.g. DM, asthma, epilepsy, etc Risk of travel-related problems e.g. Economy class syndrome, Motion sickness, jet lag Bites and stings High altitude sickness, decompression sickness Risk of accident / injury / homicide Psychological problem in travelers eg culture shock Magnitude of health problem among travelers 100,000 travelers to developing world for 1 mo 50,000 travelers will develop some sort of health problem during their trip 8,000 (8%) travelers will see a physician 5,000 (5%) travelers will be confined to bed 1,100 (1.1%) travelers will be incapacitated in their work International Society of Travel Medicine, 2007 Magnitude of health problem among travelers 100,000 travelers to developing world for 1 mo 300 travelers (0.3%) will have to be hospitalized either during their trip or upon their return 50 travelers will have to be air evacuated out of the country they are visiting 1 traveler will die What is Travel Medicine? เวชศาสตร การเด นทางและท องเท ยว ค ออะไร International Society of Travel Medicine,

3 Travel Medicine Travel Medicine is the field of medicine concerned with prevention, management and research of health problem associated with travel. Travel Medicine Medical Tourism Body of knowledge in Travel Medicine Practices in Travel Medicine Tropical medicine and infectious diseases Epidemiology of infectious diseases (globally) Preventive measure: chemoprophylaxis, vaccination, etc Risk assessment / Risk management Special need traveler eg pregnancy, immunocompromised Special itineraries eg high altitude, underwater, polar Approach to returned travelers International Health control Psychological adaptation in travelers Pre Travel assessment and counseling Risk management include vaccination/chemoprophylaxis Malaria Prevention and Prophylaxis Post Travel visit Screening of returned travelers Diagnosis and Treatment of common problem in returnedtravelers eg fever, diarrhea, rash, eosinophilia Surveillance of emerging, re-emerging or important imported diseases TMID 531 Travel Medicine Introduction to travel medicine, travel immunization (2) Immunocompromised travelers (1) Underwater medicine (3) Aviation medicine (3) Skin disorders in travelers (1) Jet lag and motion sickness (1) Pre-travel assessment in High risk travelers (1) Evaluation of ill-returned travelers (2) Visit Travel Clinic (1) Seminar (3) Practices in Travel Medicine (30 hrs) Practical vaccine usage in traveler 3 Travelers malaria 2 Malaria prevention and prophylaxis 2 Travelers diarrhea 2 Water purification for travelers 1 Returned travelers 2 Economic class syndrome 1 International health control* 3 Underwater hazards* 3 Impact to host country* 2 Psychological aspect in travelers* 2 High Altitude medicine* 3 How to run a travel clinic 1 Seminar 3 3

4 Service Part in Travel Clinic Travel Clinic at Hospital for Tropical Diseases Established in 2004 Special clinic for Thai and also foreigners Hospital For Tropical Diseases Patients served in ,000 OPD visits 2,500 admissions Services - Pre and Post travel visit Academic Research and Training center Nationality of Travelers Thai Southeast Asia Japan, Korea, Taiwan US, Canada Australia, New Zealand India, Bangladesh Africa Somalia Nigeria Mali Zambia Cameroon Others Middle Asia and Middle-east Uzbekistan Tajikistan Jordan Israel Saudi Arabia Kuwait Central and South America Argentina Chile Peru Mexico Nationality of travelers visit (n=1061) Travel Clinic of Hospital For Tropical Diseases US,Europe, AUS,NZ 35% Thai 35% Others 3% Asia 17% Africa 5% Middle east 5% 4

5 Travel Clinic Hospital For Tropical Diseases Common Problems in Travel Clinic Pre Travel Visit Risk Assessment and counseling Malaria Prevention and Prophylaxis Vaccination and immunization Post Travel Visit Screening of returned travelers Diagnosis and treatment of travel-related diseases Teaching and Training Center Research and international collaboration Ask for malaria prophylaxis Request for vaccination ill-returned Travelers Special need travelers Special itinerary Pre-Travel Visit Common Scenario Individualized risk assessment Assess risk of specific diseases e.g. Malaria Vaccine preventable diseases Accident, bite and stings Psychological issue Special group of travelers Special itinerary Recommend preventive measure A group of Thai tourists would like to take a safari in Kenya and go to Kilimanjaro Foreign travelers will travel throughout SE Asia as backpackers for 3 months University students would like to take a volunteer job in Africa for 3 months Thai workers will be deployed in PNG for 6 months Available vaccines Hepatitis vaccine (A, B, A+B) Typhoid vaccine Meningococcal vaccine JE vaccine (conventional, SA ) Cholera vaccine Rabies vaccine Influenza vaccine Pneumococcal vaccine Chicken pox vaccine MMR, TT, OPV Yellow fever vaccine 5

6 Travel Immunization Vaccine for travelers Travel Immunization Mandatory vaccine Yellow fever, Meningococcal vaccine (for Hajj pilgrims) Routine vaccine Diphtheria, Tetanus, Pertussis, MMR, Polio, BCG Recommended vaccines for travelers Hepatitis A,B Rabies vaccine JE vaccine Typhoid vaccine Meningococcal vaccine Cholera vaccine General concept of vaccine Vaccine is the most effective mean to prevent specific infectious diseases Serious adverse event including anaphylaxis is rare Live vaccine is contraindicated in pregnancy, immunocompromised host After being shot, the body takes time to develop immunity (usually 2-4 wks) Most vaccines can be administered simultaneously on the same visit General concept of vaccine Vaccination process Vaccines that require series of shots Every shot count. There is no need to re-start again Lengthen the interval between dose is acceptable, but it is not recommend to shorten the interval Accelerated schedule can be used in last minutes traveler Vaccine from different manufacture can be used interchangeably eg HBVax II and Engerix B Risk assessment for each individual Review indication and contraindication for each vaccine Counseling with the traveler about the risk and benefit Vaccine fact sheets are very useful Obtain informed consent Give the shot and observe any immediate reaction 6

7 Yellow fever endemic area Yellow fever Is a mosquito borne disease, endemic in Africa and Latin America Yellow fever vaccine certificate is required before travel into the country of risk Yellow fever vaccine Live vaccine Need to boost every 10 years Serious side effect is rare except in elderly, thymectomy patient CDC Meningitis Belt in Africa Meningococcal infection Droplet transmission especially in dry season Risk group Traveler to Saudi Arabia during the Hajj Student in dormitory (Some universities in USA, UK) Traveler to country in meningitis belt Vaccine Quadrivalent (A,C,Y,W-135) vaccine is highly effective 2 type: polysaccharide, conjugated vaccine (more immunogenic in children) Rabies vaccine Rabies vaccine Post-exposure vaccine 5 Doses of rabies vaccines Plus Immunoglobulin in WHO category III Pre-exposure vaccine 3 doses of rabies vaccine (D0, D7, D21/28) 2 boosters are required once exposed No immunoglobulin is needed 7

8 Risk of animal exposure in SE Asia Risk of being bitten = 1.11% in per month (Higher when compared to backpacker study) Risk of being licked = 3.2% in per month N = 7,681 from all around the world Median age 32 years, average length of stay 23 days 60% sought some travel health information before trip Only 11% completed rabies pre-exposure vaccination Purpose of Travel was not associated with risk Travelers from East Asian had 2.83 higher risk than travelers from Western/Central Europe Piyaphanee W, et al, PLOS NTD. 2012;6(9):e1852. doi: /journal.pntd Incidence of exposure by country Country of exposure no. exposed Average stay (month) Incident exposure per month 95% CI Thailand (n=7681) Cambodia (n=633) Vietnam (n=520) Lao PDR (n=476) Malaysia (n=325) Singapore (n=276) Indonesia (n=183) Myanmar (n=110) Philippines (n=65) Rabies outbreak in Bali Population 4 million with 2.7 million tourists per yr Before 2008, Bali thought to be rabies free island More than 300,000 dogs Outbreak occur in human cases human cases human cases human cases Piyaphanee W, et al, PLOS NTD. 2012;6(9):e1852. doi: /journal.pntd Travel to developing country Availability of medical care is limited, especially in non-tourist areas Rabies immunoglobulin is not widely available in most area outside capital city Rabies pre-exposure vaccination should be considered in high risk travelers especially in remote area where rabies immunoglobulin is not available 8

9 Risk area of JE Marfin A, et al, 2005 Japanese Encephalitis Mosquito borne disease Associated with pig farm and paddy field When develop encephalitis: High morbidity and mortality rate No specific treatment Vaccine Conventional vaccine Mouse brain vaccine New vaccine Hepatitis A prevalence Hepatitis A Food-water borne diseases Benign disease in children but more severe in the elderly Risk 3-30 /10,000 travelers (most common vaccine preventable diseases) Vaccine 2 shots at 0,6-12 month Screening for immunity may be useful in some traveler Tick Borne Encephalitis Tick Borne Encephalitis Virus 9

10 Tick borne encephalitis Transmission via Ixodes sp Tick or unpasteurized dairy product Risk in rural area of Central Europe, East Europe, Russia, and some part of Asia High risk season March to November Consider vaccination in high risk traveler eg fieldwork, biking, camping Recommended vaccine for Outbound Thai Travelers Africa Yellow fever vaccine Meningococcal vaccine Hep A/B, Polio, Tdap Consider rabies vaccine Malaria prophylaxis High altitude area e.g. Kilimanjaro Latin America Yellow fever vaccine Hep A/B, Polio, Tdap Malaria prevention Consider rabies vaccine High altitude area e.g. Bolivia, Peru China, India, Nepal ASEAN Hep A/B, Polio, Tdap JE vaccine Rabies vaccine Prevent diarrhea Malaria prevention High altitude area e.g. Nepal, Tibet JE vaccine Rabies vaccine Hep A/B, Polio, Tdap Prevent diarrhea Malaria prevention 10

11 Exotic Asia Rural Myanmar Papua New Guinea Rural Borneo Routine vaccine Tdap Rabies vaccine JE vaccine Malaria prophylaxis Personal medical kits Open mind and respect culture Do not forget risk of accident and personal security Post-travel visit Fever Diarrhea, GI problem Dermatological problem Respiratory problem Eosinophilia Asymptomatic screening Information source of Travel Medicine WHO website ( CDC website ( International society of travel medicine ( CDC Yellow book for international travelers WHO Green book Thai Travel Clinic ( Thai Society of Travel Medicine ( 11