The potential effect of temporary immunity as a result of bias associated with healthy users and social determinants on observations of influenza vaccine effectiveness; could unmeasured confounding explain observed links between seasonal influenza vaccine and pandemic H1N1 infection?

• Autori principali: Crowcroft Natasha S (Autore), Rosella Laura C (Autore)
• Natura: Libro
• Pubblicazione: BMC, 2012-06-01T00:00:00Z.
• Soggetti: article
• Accesso online: Connect to this object online.

<p>Abstract</p> <p>Background</p> <p>Five observational studies from Canada found an association between seasonal influenza vaccine receipt and increased risk of pandemic influenza H1N1 2009 infection. This association remains unexplained. Although uncontrolled confound...