Vaccine effectiveness comparison | Relevance of results | H1N1 | H3N2 | B |
---|---|---|---|---|
Vaccinated both seasons versus vaccinated prior season only ΔVEa (95% CI) ΔVE = VEboth − VEprior only | Patient and policy perspectives | 25% (14%, 35%) | 7% (− 7%, 21%) | 18% (3%, 33%) |
Vaccinated current season only versus vaccinated neither season (reference group) Pooled VEcurrent only | Patient and policy perspectives | 62% (51%, 70%) | 45% (35%, 53%) | 64% (57%, 71%) |
Vaccinated both seasons versus vaccinated current season only ΔVEa (95% CI) ΔVE = VEboth – VEcurrent only | Policy perspective | 3% (− 8%, 13%) | – 20% (− 36%, − 4%) | – 11% (− 20%, − 2%) |