Southern Hemisphere Influenza and Vaccine Effectiveness Research and Surveillance

Huang, Qiu Sue; Turner, Nikki; Baker, Michael G; Williamson, Deborah A; Wong, Conroy; Webby, Richard; Widdowson, Marc-Alain

Identification and quantification of risk factors for influenza infection and poor outcomes (hospitalization, ICU treatment, death) provides evidence to inform decisions on targeted pharmaceutical (vaccinations, antivirals), healthcare (e.g. improved treatment of comorbidities) and non-pharmaceutical (e.g. exposure to infections) interventions to reduce the risk of seasonal and pandemic influenza. Elderly people have a significantly higher risk of influenza-associated death compared with non-elderly people. 48 Additionally, the 2009 pandemic in NZ revealed that the risk of hospitalization and death was markedly higher for Maori and Pacific people, and those from the most deprived socioeconomic groups. 3, 42, 49 However, it is not clear whether these sociodemographic factors are independent risk factors for influenza. Furthermore, some chronic health conditions (high body mass index, asthma and pregnancy) have been shown to increase the risk of having a poor outcome from influenza infection. [50] [51] [52] [53] In NZ, household crowding has been identified as a risk factor for transmission of meningococcal disease, 54 rheumatic fever 55 and tuberculosis 56 and may also be contributing to higher rates of influenza for some populations. The household setting (crowding, housing conditions) may influence transmission of influenza, but these effects remain poorly understood. 57-59 SHIVERS will provide a multifaceted understanding of influenza risk that considers organism, host and environmental factors and opportunities for intervention. This comprehensive and quantitative approach will include detailed consideration of the independent contributions of host ethnicity, socioeconomic position, chronic illness status, obesity, household environment exposures and infecting virus.