To evaluate the variation of human mobility patterns in Kunming during holiday and non-holiday periods, and to assess their impact on the transmission of influenza.

We collected influenza surveillance data in Kunming from July 31, 2023, to August 4, 2024, and mobile phone signaling data from September 1, 2023, to February 29, 2024. We analyzed variations in the influenza composite index, and compared mobility indicators between holiday and non-holiday periods. We also developed an infectious disease transmission model that integrated human mobility using mobile phone signaling data. The differences in the total number of cumulative influenza cases under holiday and non-holiday scenarios to quantify the impact of holidays on influenza transmission.

During the holiday period, the influenza composite index showed a downward trend, followed by an upward trend after the public holidays. The average daily number of travelers and average travel frequency per person during the National Day and Mid-Autumn Festival (48.36/10 000, 0.62 per person), Spring Festival (33.24/10 000, 0.48 per person), and winter vacation(51.87/10 000, 0.69 per person) were lower than those on regular days (all P < 0.05), whereas there was no significant difference on New Year's Day (Z=-0.71, P=0.531). Model simulations indicated that different holidays had varying impacts on the transmission of influenza: the Spring Festival reduces the cumulative number of flu cases by 1 556, while the National Day, Mid-Autumn Festival, New Year's Day, and winter vacation increase the cases by 867, 11, and 1 548, respectively. Additionally, substantial spatial heterogeneity was observed across different administrative districts.

Holidays altered the human mobility patterns and affect the transmission of influenza in Kunming. The impact varied across different types of holidays. In the future, attention should be paid to the interaction between holidays, human mobility, and influenza transmission.