This document provides an overview of information gained from influenza surveillance in New Zealand in 2016. The New Zealand influenza surveillance system compiles information from a variety of sources on disease burden, epidemiology, viral aetiology, risk factors, clinical presentation and outcomes, and vaccine effectiveness. The influenza surveillance system is in place to detect influenza epidemics/pandemics, inform vaccination policy and vaccine strain selection, and guide public health control measures. NZ influenza surveillance also contributes to these activities at a global level.
2016 Influenza Activity
New Zealand conducts both hospital- and general practice (GP) based surveillance, because these systems capture disease presentations at different levels of severity. Due to differences in care seeking and disease severity, the combination of these systems also allows for a better representation of the burden of influenza in NZ. The very young (under 5 years old), older adults (65 years or older), and those of Pacific peoples ethnicity are more likely to be admitted in hospital whereas school-aged children (5–19 years old), adults (20–49 years old), and Asians are more likely to visit GPs. Visits to the GP (Figure 1) and hospital for acute respiratory illnesses were at a low level during 2016. Influenza-like illness consultation rates varied across District Health Boards (DHBs), with the highest rates reported from Tairawhiti and South Canterbury DHBs.