The impact of influenza and influenza-like illness on productivity and healthcare resource utilization in a working population.

Four hundred and eleven subjects who either reported to Occupational Health at onset of influenza or influenza-like illness (I/ILI) symptoms or on return to work completed questionnaires on entry to the study and after 28 days. On average they were incapacitated or confined to bed for 2.4 days, missing 2.8 days from work per episode of illness. On return to work, they reported reduced effectiveness and inability to resume normal activity until a mean 3.5 days after the onset of symptoms. Each participant reported a mean of 6.5 I/ILI symptoms. There was a positive correlation between the number of symptoms and bed days (r = 0.24) and missed work days (r = 0.18). There was a positive correlation between the number of healthcare contact and the number of reported symptoms (r = 0.23). A relatively high level of contact with general practitioners and pharmacists was observed and there was substantial use of both prescription and over-the-counter medication. In conclusion, the impact of I/ILI on productivity in a working population and the resultant cost to employers and employees may be considerable.