People newly arrived in Canada may be susceptible to vaccine preventable diseases. For example, a Canadian study showed that more than one-third of new immigrants and refugees, particularly women, were susceptible to measles, mumps, or rubella.
Immunization of persons new to Canada is often challenging because:
People new to Canada often return to their country of origin to visit friends and relatives. During such visits, people new to Canada, and particularly their Canadian born family members, may be exposed to risks for vaccine preventable diseases which need to be considered when evaluating immunization status and recommending vaccines.
New immigrants, refugees and internationally adopted children may lack immunizations and/or immunization records. Vaccination should only be considered valid if there is written documentation of administration of vaccine at ages and intervals comparable with the Canadian schedule. Although the potency of vaccines administered in other countries can generally be assumed to be adequate, immunization schedules vary. The age at immunization (e.g., 9 months of age for immunization against measles in some countries), the number of doses, and the intervals between doses should be carefully reviewed and compared with Canadian and provincial/territorial recommendations to determine the need for additional doses of vaccines.
In many countries outside of Canada, mumps and rubella vaccines are in limited use, and measles vaccine alone is given. Haemophilus influenzae type b (Hib), hepatitis B (HB), hepatitis A (HA), varicella, pneumococcal conjugate, and meningococcal conjugate vaccines are also in limited use. An adult booster of pertussis vaccine is a relatively new recommendation in developed countries. Refer to World Health Organization (WHO) information on vaccination schedules in other countries. Refer to Immunization of Persons with Inadequate Immunization Records in Part 3 for additional information.
Studies of internationally adopted children have shown that, despite written documentation of adequate immunizations, serologic evidence of protection against diphtheria and tetanus may be lacking. Recommendations regarding an approach to vaccinating these children vary and include:
Judgment is required to determine the best option in any particular situation.
Family members travelling outside of Canada to adopt a child should receive all appropriate routine and travel immunizations before departure from Canada to pick up adopted children (refer to Immunization of Travellers in Part 3 for additional information). Other close contacts, including extended family members, should have up-to-date routine immunizations with some additional considerations. For example, many countries continue to use oral polio vaccine (OPV). Following receipt of OPV, poliovirus can be present in the throat for 1 to 2 weeks and can remain in feces for several weeks. Although rare, close contacts of children who have received OPV may become infected with vaccine-derived polio virus if they are not adequately immunized. Therefore, ensuring up-to-date polio vaccination of close contacts is important. In addition, HA vaccine is recommended for pre-exposure prevention in household or close contacts of children adopted from HA endemic countries and HB vaccine is recommended for pre-exposure prevention in close contacts of children adopted from HB endemic countries if the adopted child is HB surface antigen (HBsAg) positive.
Citizenship and Immigration Canada typically conduct Immigration medical examinations (IME) before foreign nationals (non-Canadian citizens) arrive in Canada. They are required for:
If the IME is not conducted prior to arrival (such as refugee claimants in Canada) it is done as soon as possible after arrival.
Health care providers in Canada who see persons newly arrived in the country should prioritize assessing and updating immunizations for persons new to Canada because the IME does not include a review of immunization status. In addition, health care providers should perform a complete health assessment, including comprehensive testing for a variety of chronic and non-vaccine preventable diseases.
As part of the health assessment, the following tests should be completed (if not already available from a completed IME) to determine the need for vaccines or contraindications to vaccination:
Persons newly arrived in Canada lacking adequate documentation of immunization should be considered unimmunized and started on an immunization schedule appropriate for their age and risk factors unless known to be immune by serologic testing. In addition to the routine immunization schedule, certain vaccines may be recommended for people newly arrived in Canada as follows:
Vaccination against HA should be considered for people from countries that are endemic for HA. Individuals born in developing countries are more likely to be immune to HA; therefore, testing for immunity before administering HA vaccine to persons from HA endemic countries should be considered. Household or close contacts of children adopted from HA endemic countries should be immunized with HA-containing vaccine. Persons new to Canada should be tested for HB and HC infection and persons chronically infected with HB (HB carriers) or HC should be vaccinated against HA, based on susceptibility testing if indicated. Refer to Hepatitis A Vaccine in Part 4 for additional information.
All persons from a country that is endemic for HB should be assessed and vaccinated against HB if not immune and not infected. Individuals born in developing countries are more likely to be carriers of HB, necessitating vaccination of their sexual and household contacts based on review of their serologic test results. HB vaccine is recommended for all household contacts whose families have immigrated to Canada from areas where there is a high prevalence of HB and who may be exposed to HB carriers through their extended families or when visiting their country of origin. Children adopted from countries in which there is a high prevalence of HB infection should be screened for HBsAg and, if positive, household or close contacts in the adopting family should be immunized before adoption or as soon as possible thereafter. Refer to Hepatitis B Vaccine in Part 4 for additional information.
Persons new to Canada from high hepatitis C endemic countries should be tested for HC antibody and persons chronically infected with HC should be vaccinated against HB if susceptible. Countries with high rates of chronic infection are Egypt (15%), Pakistan (4.8%) and China (3.2%).
Unless known to be immune to rubella because of prior serology or documentation of a dose of rubella-containing vaccine, rubella-containing vaccine should be given to persons new to Canada; pre-immunization serology is not needed. Unless there is a contraindication to use, rubella susceptible people should be immunized with one dose of a measles-mumps-rubella-containing (MMR) vaccine as soon as possible after entry to Canada. Foreign-born women of childbearing age from countries where rubella-containing vaccine is not in use should be a priority. Susceptible women who are pregnant should receive MMR vaccine after delivery. Refer to Rubella Vaccine in Part 4 for additional information.
In tropical countries, varicella occurs at an older age and most tropical countries do not have varicella immunization programs. People from tropical regions are more likely to be susceptible to varicella and should be a priority for varicella testing and immunization if non-immune. Susceptible women who are pregnant should be vaccinated after delivery. Refer to Varicella (Chickenpox) Vaccine in Part 4 for additional information.
Children who have received one or more doses of polio vaccine before arriving in Canada should have their vaccine series completed with IPV-containing vaccine as appropriate for age. Similar to vaccination of children, vaccination of adults is recommended to prevent the introduction and circulation of polio. A complete series of IPV-containing vaccine is recommended for previously unimmunized adults who are also receiving a primary series of tetanus toxoid-containing vaccine. For other adults who are unvaccinated against polio, vaccination efforts should be focused on those who are at increased risk of exposure to polioviruses including: family or close contacts of internationally adopted infants who may have been or will be vaccinated with OPV vaccine, and travellers to, or persons receiving travellers from, areas where poliovirus is known or suspected to be circulating. Refer to the WHO Polio Global Eradication Initiative for the current status of polio around the world. Adults previously immunized with polio vaccine and at increased risk of exposure to polio should receive a single lifetime booster dose of IPV-containing vaccine.
When persons new to Canada return to visit their country of origin, vaccines may be indicated. For example, HA and HB vaccine are often indicated if not previously received. Additional vaccines, such as typhoid, may also be indicated before a person new to Canada visits his/her country of origin. Refer to the Committee to Advise on Tropical Medicine and Travel (CATMAT) Statement on Visiting Friends and Relatives in development.