Immunization Prior to Travel to Endemic Areas

Specific vaccination recommendations vary among countries or even within a given country. Local or country-specific guidelines should be consulted.

1. Routine vaccinations against hepatitis A, hepatitis B, tetanus, pertussis, diphtheria, influenza, and measles: see Vaccines: Hepatitis A, see Vaccines: Hepatitis B, see Vaccines: Diphtheria and Tetanus, see Vaccines: Pertussis, see Vaccines: Seasonal Influenza, see Vaccines: Measles, Mumps, and Rubella. Some vaccinations listed below are also part of the primary childhood vaccination schedules in Canada and the United States. In such cases, only travel-related information is listed here; for details on the primary series, see the corresponding chapters.

2. Vaccinations are determined by travel destination (endemic regions), local conditions, and the type of planned activities. Recommendations may change rapidly and require individual assessment of indications followed by appropriate vaccinations; this is performed by specialist vaccination, travel medicine, or infectious disease clinics.

1) Cholera: see Vaccines: Cholera.

2) Japanese encephalitis is endemic in many southeastern and western Pacific parts of Asia, with transmission peaking in summer or fall in many, but not all, endemic regions. The risk is highest for patients traveling in rural areas within endemic countries associated with rice agriculture or those participating in outdoor activities, such as hiking or camping. Individuals should consider vaccination if they are spending >30 days in a rural area, or if they are spending <30 days in a rural area and are participating in outdoor activities, especially in the evenings. The vaccine contains inactivated viruses and is approved for administration in those >18 years old. Primary vaccination involves 2 IM doses given at a 28-day interval. The primary series should be completed 10 to 14 days prior to potential exposure. In the case of continued exposure, give 1 IM booster dose 12 months after the primary series. The pregnancy safety data are limited. Immunocompromised patients may receive the vaccine but it should be noted that antibody titers may be suboptimal.

3) Meningococcal infections: see Vaccines: Neisseria meningitidis (Meningococcal) Infections. Which meningococcal vaccination(s) a traveler should receive depends on the circulating serotypes in the area of travel; for instance, while meningococcal group C (MenC) vaccine should be given to all travelers, meningococcal group B (MenB) vaccines should only be given when traveling to hyperendemic areas or to an area of a known outbreak with serotype B. In traveling individuals aged 12 to 24 years, quadrivalent conjugate meningococcal vaccines (Men-C-ACYW) should be used. Vaccination is recommended when traveling to areas of sub-Saharan Africa within the “meningitis belt,” stretching from Senegal to Ethiopia. Travelers to Saudi Arabia for the purposes of Umrah or Hajj or for seasonal work are required to have proof of 1 IM dose of Men-C-ACYW vaccination. Booster doses are recommended every 5 years for travelers aged >7 years at ongoing risk.

4) Poliomyelitis: see Vaccines: Poliomyelitis.

5) Rabies: see Vaccines: Rabies. Travelers to endemic areas (eg, Asia, Africa, South America, Central America) at higher risk include those whose activities will bring them into contact with wild or domestic animals and those who engage in cave exploration, hunting, or trapping. Travelers visiting remote areas where prompt medical care will be difficult to obtain should also consider vaccination for preexposure prophylaxis. All travelers should be counseled to seek medical attention to complete postexposure prophylaxis if they are bitten by a potentially rabid animal.

6) Tick-borne encephalitis: see Vaccines: Tick-Borne Encephalitis.

7) Typhoid fever: see Vaccines: Enteric (Typhoid) Fever.

8) Yellow fever is endemic—and intermittently epidemic—in sub-Saharan Africa and the central and northern regions of South America. Yellow fever vaccines contain live attenuated viruses. In Canada, these vaccines are only available at Yellow Fever Vaccination Centres designated by the Public Health Agency of Canada. Unique among many vaccine-preventable illnesses, an International Certificate of Vaccination or Prophylaxis for yellow fever vaccination is required to gain entry into many endemic countries. These certificates may only be issued by authorized clinics and, based on recent changes to the World Health Organization (WHO) regulations, are valid for the life of the individual, beginning at day 10 after vaccination. Primary vaccination in individuals 9 months of age to 59 years of age is a single dose administered subcutaneously, with booster vaccination administered every 10 years if indicated. Primary vaccination has a seroconversion rate of 95% to 99%. Booster vaccination is only recommended by the Committee to Advise on Tropical Medicine and Travel (CATMAT) in Canada for the following circumstances: pregnant patients, immunosuppressed patients, individuals who underwent a hematopoietic stem cell transplant after receipt of the primary series, patients with HIV infection, and yellow fever virus laboratory workers. The vaccine should not be given to children <6 months of age due to an increased risk of encephalitis and to children 6 to 8 months of age due to poor immunogenicity, and it should only be given with extreme caution to those ≥60 years of age due to the risk of yellow fever vaccine–associated neurotropic disease (1.6/100,000 doses) and yellow fever–vaccine associated viscerotropic disease (1/100,000 doses). A careful risk assessment should be undertaken by a physician and their patient prior to offering yellow fever immunization if the patient is pregnant, immunocompromised, or both.