Table 2 Inactivated inﬂuenza vaccine compared with live attenuated inﬂuenza vaccine Inactivated vaccine (TIV) Type of vaccine Killed virus Route of administration Intramuscular injection Vaccine strains updated Annually Number of strains included 2 inﬂuenza A 1 inﬂuenza B Inﬂuenza A strains in 2005 vaccine California/7/2004 (H3N2) New Caledonia/20/99 (H1N1) Inﬂuenza B strain in 2005 vaccine Shanghai/361/2002 Approved age ≥6 months Approved for persons with chronic obstructive pulmonary disease Yes Approved for other high-risk persons Yes Can be administered to family members or close contacts of high-risk persons not severely immunosuppressed Yes Can be administered to family members or close contacts of immunosuppressed persons not requiring a protected environment Yes Can be administered to family members or close contacts of immunosuppressed persons requiring a protected environment Yes Can be administered simultaneously with other vaccines Yes Can be administered within 4 weeks of another inactivated vaccines Yes Can be administered within 4 weeks of another live vaccines Yes Preventing inﬂuenza in COPD Live attenuated vaccine(LAIV) Live virus Intranasal spray Annually 2 inﬂuenza A 1 inﬂuenza B California/7/2004 (H3N2) New Caledonia/20/99 (H1N1) Shanghai/361/2002 5–49 years No No Yes Yes Yes Yes Inactivated vaccinepreferred Yes, but prudent to space 4 weeks apart with inﬂuenza vaccines administered after 1976 (Kaplan et al 1982). Efﬁcacy and effectiveness of the inﬂuenza vaccine Efﬁcacy and effectiveness of inﬂuenza vaccination have been demonstrated in children, adults, elderly, and patients with high-risk conditions. In health persons the vaccine is 70%–80% effective (Harper et al 2005; Fukuda et al 2004; CDC 2006). The US Preventive Services Task Force (1996) has strongly recommended that clinicians provide inﬂuenza vaccina- tion to patients with COPD, based on the good evidence that improved health outcomes and beneﬁts substantially outweigh harms. The vaccine is effective in preventing secondary com- plications and reducing the risk for inﬂuenza-related hospi- talization and death among adults aged 65 years with and without high-risk medical conditions. One study assessing vaccine effectiveness in different high-risk subpopulations showed that in patients aged more than 64 years with cardio- pulmonary disease (Nichol et al 1998), inﬂuenza vaccination International Journal of COPD 2007:2(1) reduced inﬂuenza-related hospitalizations by 29% and deaths from all-cause by 49%. In patients with other chronic condi- tions such as diabetes, renal disease, rheumatologic disease, and stroke, inﬂuenza vaccination reduced hospitalizations by 32% and deaths from all-cause by 64%. In the healthy persons, inﬂuenza vaccination reduced hospitalizations by 49% and deaths from all-cause by 55%. Nonrandomized studies in individuals aged >64 years with or without chronic medical conditions have reported that vaccine reduces pneumonia and inﬂuenza hospitalizations by 18% to 52% and deaths from all causes by 27% to 70% (Gross et al 1995; Nichol et al 1998, 1999; Fedson et al 1992; Nordin et al 2001).One meta-analysis estimated that inﬂuenza vaccine reduced inﬂuenza-like illness by 33% (95% conﬁdence interval [CI]: 27%–38%), hospitalizations from pneumonia and inﬂuen- za by 33% (95% CI: 27%–38%), and mortality from all causes by 50% (95% CI: 46%–56%) in community-dwelling elderly (Vu et al 2002). A second meta-analysis including cohort studies in both nursing homes and noninstitutionalized elderly population estimated that inﬂuenza vaccine reduced respiratory illness by 56% (95% CI: 39%–68%), hospitalizations by 47