Seasonal influenza

Abstract

Influenza is defined by NICE (2015) as ‘an acute respiratory illness caused by RNA viruses of the orthomyxoviridae family’ and there are three types: Influenza A; Influenza B and Influenza C. Influenza is identified by the World Health Organisation (WHO) (2012) as having an annual infection rate of between 5% and 10% in adults and between 20% and 30% in children. In the UK, it usually occurs between October and May and patients who become infected will generally present with symptoms which include fatigue; dry cough; headache; sore throat and aching muscles, within 2-3 days after being exposed to the virus (NICE, 2015). For some, infection with influenza can lead to complications which include pneumonia; otitis media; acute bronchitis and severe fever. The risk from these complications is greater in those deemed at most risk and this includes people aged over 65 years; pregnant women; those with underlying long term conditions and the immunosuppressed (NHS Choices, 2015).