Canadian Immunization Guide
Seventh Edition - 2006

[Previous] [Table of Contents] [Next]

Part 1
General Guidelines

Timing of Vaccine Administration

For most products that require more than one dose or booster doses for full immunization, intervals longer than those recommended between doses do not lead to a reduction in final antibody concentrations. Therefore, as a general rule, interruption of a series of vaccinations for any reason does not require starting the series over again, regardless of the interval elapsed. By contrast, doses given at less than the recommended interval may result in less than optimal antibody response and should not be counted as part of a primary series.

There are obvious practical advantages to giving more than one vaccine at the same visit, especially for infant immunization schedules, for travel immunization or when there is doubt that an individual will return for further doses of vaccine. No increase in the frequency or severity of clinically significant side effects has been observed. The immune response to each antigen is generally adequate and comparable to that found in persons receiving these vaccines at separate times.

Simultaneous administration of childhood vaccines (diphtheria, tetanus, acellular pertussis [DTaP]; inactivated poliovirus [IPV]; Haemophilus influenzae type b [Hib]; measles, mumps, and rubella [MMR]; varicella; pneumococcal conjugate and hepatitis B vaccine) is encouraged for children who are the recommended age to receive these vaccines and for whom no contraindications exist. If not given during the same visit as other live virus vaccines, administration of two live vaccines should generally be separated by at least 4 weeks. A number of vaccines that deliver protection against more than one disease (i.e., combination vaccines) are available and approved for use in Canada.

Simultaneously administering pneumococcal polysaccharide vaccine and inactivated influenza vaccine elicits a satisfactory antibody response without increasing the incidence or severity of adverse reactions. Therefore, simultaneous administration is strongly recommended for all persons for whom both vaccines are indicated.

Different formulations of vaccine against the same disease (e.g., pneumococcal conjugate and pneumococcal polysaccharide vaccine or meningococcal conjugate and meningococcal polysaccharide vaccine) cannot be given simultaneously, and a minimum time interval should elapse between the administration of the two formulations.

Vaccines administered simultaneously should be given using separate syringes at separate sites unless otherwise specified by the manufacturer, with consideration being given to the precautions that apply to each individual vaccine.

MMR vaccine can decrease the immunologic response to tuberculin skin testing, resulting in false-negative results. Therefore, tuberculin skin tests should be given either on the same day as MMR immunization or at least 4-6 weeks later. The effect of other live virus vaccines such as varicella and yellow fever vaccines on tuberculin reacitivity is currently unknown, and no recommendations for postponement of tuberculin skin testing can be made at this time.

Please refer to the specific vaccine chapters in this Guide for further information.

Selected references

Centers for Disease Control and Prevention. General recommendations on immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP) and the American Academy of Family Physicians (AAFP). Morbidity and Mortality Weekly Report 2002;51(RR-2):1-35.

Centers for Disease Control and Prevention. Travelers' health: yellow book. Health information for international travel, 2005-2006. URL: <http://www.cdc.gov/travel/>.

Centers for Disease Control and Prevention. Typhoid immunization: recommendations of the Advisory Committee on Immunization Practices (ACIP). Morbidity and Mortality Weekly Report 1994;43(RR-14):1-7.

Centers for Disease Control and Prevention. Yellow fever vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2002. Morbidity and Mortality Weekly Report 2002;51(RR-17):1-10.

DeStefano F, Goodman RA, Noble GR et al. Simultaneous administration of influenza and pneumococcal vaccines. Journal of the American Medical Association 1982;247(18):2551-54.

Halperin S, McDonald J, Samson L et al. Simultaneous administration of meningococcal C conjugate vaccine and diphtheria-tetanus-acellular pertussis-inactivated poliovirus-Haemophilus influenzae type b conjugate vaccine in children: a randomized double-blind study. Clinical and Investigative Medicine 2002;25(6):243-51.

King GE, Hadler SC. Simultaneous administration of childhood vaccines: an important public health policy that is safe and efficacious. Pediatric Infectious Disease Journal 1994;13(5):394-407.

Yvonnet B, Coursaget P, Deubel V et al. Simultaneous administration of hepatitis B and yellow fever vaccines. Journal of Medical Virology 1986;19(4):307-11.

[Previous] [Table of Contents] [Next]