RESUMO
Objective To estimate the outpatient rate of influenza-related influenza-like illness (ILI) for children younger than 5 years in Suzhou municipal districts. Methods From October 2011 to March 2017, we conducted a prospective surveillance program on ILI for children under 5 years in outpatient settings of Soochow University Affiliated Children’s Hospital (SCH). The throat swabs were collected and tested for influenza viruses by RT-PCR. Based on the healthcare utilization surveys and population data, the number of visits and the outpatient rate of influenza-related ILI for children younger than 5 years in Suzhou municipal districts were estimated. Results During 2011-2017, in total, there were 45 930 estimated influenza-related ILI cases younger than 5 years in Suzhou municipal districts, which consisted of 7 490 influenza A/H1N1 cases, 17 843 influenza A/H3N2 cases and 20 597 influenza B cases. The estimated outpatient rate of influenza-related ILI was 6.4% in 2011-2017, which was highest in 2011-2012, 20.5%, and the lowest in 2012-2013, 2.4%. Conclusion The number of visits and the outpatient rate of influenza-related ILI in children younger than 5 years was high in Suzhou municipal districts.