The immunization requirements for travel will vary according to the traveller's age, physical health, existing medical conditions, and the nature of travel (whether the traveller is staying in urban hotels, or visiting remote rural areas), and its duration.

There is no single schedule for the administration of immunization agents to travellers. Each schedule must be personalized according to the individual traveller's immunization history, the countries to be visited, the type and duration of travel, and the amount of time before departure. Routine immunizations recommended for Canada (diphtheria, pertussis, tetanus, measles, mumps, rubella, poliomyelitis and Hib) should be updated as needed. The personalized schedule will be dependent upon which immunizing agents are to be administered.

With some notable exceptions, most immunizing agents can be given simultaneously at different sites. Cholera and yellow fever vaccine should be given at least 3 weeks apart. The efficacy of MMR may be impaired by the administration of immune serum globulin less than 2 weeks after the vaccine. If immune serum globulin is given first, an interval of 3 to 10 months may be required before giving MMR. Mefloquine or other antibiotics active against Salmonella typhi may interfere with the response of the oral typhoid vaccine.

Specific recommendations on immunization for travel are available in the Canadian Immunization Guide, Fifth Edition, 1998. This guide also contains important recommendations and modifications to the routine immunization schedule for infants and young children intending to travel internationally.

Depending on the aforementioned considerations, travel health clinics and family physicians should consider the following immunizations for travellers:

Yellow Fever

Yellow fever is the only vaccination required as a condition of entry under the World Health Organization's International Health Regulations. A valid International Certificate of Vaccination, issued within the past 10 years, is mandatory for entry to 21 countries in Central Africa and South America. Some 102 other countries not in yellow fever endemic zones have requirements for proof of vaccination from travellers who have passed through a yellow fever zone. The decision to vaccinate against yellow fever will depend on the itinerary of the individual traveller and the specific requirements of the countries to be visited (including stopovers). An up-to-date list of countries requiring yellow fever vaccination. is available.

Only designated yellow fever vaccination clinics can provide International Certificate of Vaccination in Canada. For more information, contact Travel Medicine Program at (613) 957-8739.

Poliomyelitis

All travellers should be adequately immunized against polio. If the traveller has been previously immunized, one dose of OPV or IPV should be given, if more than 10 years have elapsed since the last dose. For partially immunized or unimmunized persons, refer to the poliomyelitis vaccine section of the Canadian Immunization Guide, Sixth Edition, 2002. Note: Oral polio vaccine should not be given to immunocompromised individuals, nor to individuals who share accommodation with an immunocompromised person.

Measles

Two doses of measles vaccine are recommended for all unimmunized travellers aged > 1 year who were born after 1970 and who are en route to a measles endemic area, unless there is serologic proof of immunity or physician documentation of prior measles.

Rubella

A single dose, alone or in combination with measles and mumps vaccine, is recommended for all unimmunized children and for susceptible women of child-bearing age.

Tetanus and Diphtheria Toxoids

Boosters are recommended every 10 years. This is particularly important because of the resurgence of diphtheria in countries of Eastern Europe.

Typhoid

Typhoid vaccine is recommended for travellers who will have prolonged exposure to potentially contaminated food and water, in smaller cities and villages or rural areas off the usual tourist itineraries. Vaccination can be by parenteral inactivated Vityphium vaccine or by live-oral (liquid or enteric-coated capsules) attenuated vaccine Ty21A.

Hepatitis B

The vaccine should be given to travellers residing more than 6 months in areas with high levels of endemic Hepatitis B, those doing medical work, and those who are likely to have contact with blood or sexual contact with residents of such areas.

Hepatitis A

Protection against Hepatitis A with Hepatitis A vaccine is recommended for travellers to developing countries, especially rural areas or where the hygienic quality of the food and water supply is likely to be poor and hepatitis A is endemic. Two inactivated hepatitis A vaccines are licensed in Canada along with a combined hepatitis A and hepatitis B vaccine. The duration of protection and the need for boosters is unknown. However, it is expected that protective levels of antibody may lasts for at least 20 years.

For infants < 1 year and in individuals for whom the vaccine is contraindicated, Immune Serum Globulin (ISG) may be used. ISG provides protection for only 4-6 months and persons living for prolonged periods in developing countries may require repeat dosing. The need for repeated doses may be determined by testing for total anti-HAV antibodies to determine susceptibility. ISG produced in developing countries may not meet the standards for purity used in most developed countries. Persons needing repeated doses overseas should use products that meet Canadian licence requirements.

Rabies

Pre-exposure immunization should be considered for persons intending to live or work in highly endemic areas, especially where rabies control programs for domestic animals are inadequate. Travellers should be warned that in the event of exposure to a rabid animal, two booster doses should be given as soon as possible, regardless of any previous immunization against rabies.

Japanese encephalitis

Japanese encephalitis is a mosquito-borne viral encephalitis that occurs throughout most of East Asia from India east to Korea and Japan, in epidemics in late summer and early fall in temperate areas including Korea, and sporadically throughout the year in tropical areas of Southeast Asia including Thailand. The vaccine is recommended for travel of more than 4 weeks in rural areas of endemic countries. Specifically: temperate regions, during summer and autumn of all of Bangladesh, Burma, China, India, Japan, Kampuchea, Korea, Laos, Nepal; northern Thailand, northern Vietnam, eastern areas of the former Soviet Union; tropical regions during the rainy season; southern India, Indonesia, Malaysia, the Philippines, Singapore, Sri Lanka, Taiwan, southern Thailand and southern Vietnam.

European tick-borne encephalitis

European tick-borne encephalitis is similar to other mosquito-borne viral encephalides, but is transmitted by tick bite. A vaccine is recommended for long term travellers to endemic areas of Russia, other countries that comprised the former Soviet Union and parts of Europe, from April through August. The vaccine is not licensed in Canada, but is available in Austria and from travel clinics in London, England. In Canada, it may be possible to obtain the vaccine through the Emergency Drug Release Program. Physicians may make a request for such a release to the Special Access Programme, Health Protection Branch, (613) 941-2108.

Additional Information

Additional information is available through this system, please consult the following documents:

• Document # 235 General Advice for Travellers
• Document # 207 Yellow Fever Requirements
• Document # 205 Canadian Yellow Fever Clinics
• Document # 211 European Tick borne Encephalitis

References

Canadian Immunization Guide, Fourth Edition, 1993. Health Canada.
Guide d'Intervention Santé-Voyage, 1994. Ministère de la Santé et des Services Sociaux, Québec.

[Information for Travellers] [Information for Travel Medicine Professionals]