Burden of influenza-like illness and those associated with respiratory viruses
During 2013-2015, among individuals of any age the estimated mean annual number of ILI episodes was 27,773,390 (rate: 51,383 per 100,000 population) (Table S2) of which 7,232,910 (26.0%; rate: 13,381 per 100,000 population) were medically attended (Table S3). The ILI rates were highest in infants and declined with increasing age (Figure 3 and Table S2). Overall, among patients with ILI, rhinovirus had the highest rate (7,221 per 100,000 population) followed by influenza (6,443 per 100,000 population) and adenovirus (1,364 per 100,000 population) (Figure 2 and Table S2). A similar ranking was observed among individuals aged ≥5 years (Figure 2 and Table S2). Among children aged <5 years, rhinovirus had the highest rate (9,424 per 100,000 population) followed by influenza (7,440 per 100,000 population) and RSV (4,774 per 100,000 population). The respiratory viruses-associated ILI rates were highest in infants and declined with increasing age with the exception of influenza and adenovirus where the highest rates were among individuals aged 5-24 years (Figure 3 and Table S2) and PIV type 2 where the highest rate was among individuals aged ≥65 years (Figure 5 and Table S8). The rates of medically and non-medically attended respiratory viruses-associated ILI are provided in Tables S3, S4 and S8.