Abstract：Objective To analyze the characteristics of outbreaks of influenza-like illness (ILI) cases in Guangzhou City from 2019 to 2020, and to provide a scientific basis for influenza prevention and control. Methods We collected the data regarding ILI outbreaks and information about public health emergency events reported in 11 districts of Guangzhou City during 2019-2020 through National Influenza Surveillance Information System in China and Public Health Emergency Management Information System. Descriptive epidemiological method was used to analyze the epidemiological characteristics of ILI outbreaks in Guangzhou City from 2019 to 2020. Results A total of 197 ILI outbreaks were accumulatively reported in Guangzhou from 2019 to 2020, mainlyconcentrating in April, May and December. 183 outbreaks were reported in 2019 and 14 were reported only from January toFebruary, 2020. ILI outbreaks were reported in all 11 districts of the city, of which more than 30 outbreaks were reported in Huadu District (n=48), Huangpu District (n=47) and Nansha District (n=32). ILI outbreaks mainly occurred in primary schools (n=135, 68.53%), secondary schools (n=39, 19.80%) and childcare institutions (n=11, 5.58%). Laboratory test results showed that there were 124 (62.94%) cases of influenza A (H3N2), 38 (19.29%) cases of influenza B (Victoria), 15 (7.61%) cases of influenza A (H1N1) pdm09, 11 (5.58%) cases of mixed type, and 9 (4.57%) cases of unclassified type. Influenza A (H3N2) was the absolute dominant strain in 2019-2020. Conclusion The outbreaks of ILI cases in Guangzhou City from 2019 to 2020 were mainly concentrated in April-May, 2019 and December, 2019 to January, 2020. Influenza A (H3N2) was the absolute predominant strain druing 2019-2020. COVID-19 prevention and control measures taken in 2020 greatly reduced the intensity of the influenza epidemic in Guangzhou City.
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