Clinical meaning
The clinician prescribes and administers adult immunizations according to the National Advisory Committee on Immunization (NACI) guidelines in Canada. Key vaccines: influenza (annually for all adults, particularly high-risk groups -- immunocompromised, chronic disease, healthcare workers, pregnant women; quadrivalent inactivated or recombinant preferred, high-dose or adjuvanted formulations for adults 65 and older); pneumococcal (PCV20 or PCV15 followed by PPSV23 for adults 65 and older and high-risk adults -- immunocompromised, chronic lung/heart/liver/kidney disease, diabetes, asplenia, cochlear implants); herpes zoster (Shingrix -- recombinant adjuvanted, two-dose series for adults 50 and older, immunocompromised adults 18 and older; superior to the live Zostavax with 97% efficacy versus 51%); Td/Tdap (Tdap once in adulthood if not previously received, Td booster every 10 years; Tdap in every pregnancy at 27-32 weeks to provide passive antibody transfer to the neonate); HPV (Gardasil 9 for adults up to age 26, shared decision-making for ages 27-45). The clinician assesses immunization history, identifies contraindications (anaphylaxis to vaccine component, live vaccines in immunocompromised patients except specific exceptions, pregnancy for live vaccines), manages vaccine hesitancy with evidence-based motivational interviewing, recognizes and manages adverse reactions (anaphylaxis: epinephrine 0.3-0.5 mg IM, observation period), and maintains proper cold chain storage and documentation.