First evidence of a pro-inflammatory response to severe infection with influenza virus H1N1
Centro Nacional de Microbiología, Instituto de Salud Carlos III (Campus Majadahonda); Carretera Majadahonda-Pozuelo, Km 2.2; 28220 Majadahonda (Madrid), Spain
Critical Care 2010, 14:115 doi:10.1186/cc8846
See related research by Bermejo-Martin et al., http://ccforum.com/content/13/6/R201, related letter by Krstíc, http://ccforum.com/content/14/2/410 and related letter by Kawashima et al., http://ccforum.com/content/14/2/411Published: 11 February 2010
The great majority of infections caused by the pandemic variant of the influenza virus (nvH1N1) are self-limited, but a small percentage of patients develop severe symptoms requiring hospitalization. Bermejo-Martin and colleagues have presented a pilot study describing the differences in the early immune response for patients both mildly and severely infected with nvH1N1. Patients who develop severe symptoms after nvH1N1 infection showed Th1 and Th17 'hypercytokinemia', compared to mildly infected patients and healthy controls. The mediators involved with the Th1 and Th17 profiles are known to be involved in antiviral, pro-inflammatory and autoimmune responses. This is the first work reporting the association of a pro-inflamatory immune response with a severe pandemic infection, although it is likely that more studies are needed to understand the detrimental or beneficial roles these cytokines play in the evolution of mild and severe nvH1N1 infection.