Surveillance of influenza in Northern Ireland 2012-2013

The 2012/13 influenza season started earlier than in 2011/12; however it lasted longer, with GP consultation rates being elevated for approximately four months. Clinical indices began to increase in late December and peaked in early January, with the only two instances of community syndromic indicators exceeding the baseline threshold occurring in this month. GP influenza-like illness consultation rates in 2012/13 were higher than those in the 2011/12 season for the majority of the season but remained low overall.Overall no one age-group appeared predominantly affected; however, older adults predominated during the peak period, with rates increasing in children during February. Rates for those aged 65 and over increased late in the season, and this was associated with influenza outbreaks in care homes for the elderly.