Economic burden of pertussis, its influencing factors, and hospitalization determinants among older adults (≥ 60 years) in Zhejiang, China: A cross-sectional study (2024–2025)

Backgroud Pertussis resurgence is a growing global public health concern. In Zhejiang Province, China, reported pertussis cases surged 38-fold in 2024 compared to 2023, with 632 cases in adults ≥ 60 years—ranking highest nationwide. However, the economic burden of pertussis in this demographic remains unquantified in China, a gap that impedes optimizing prevention strategies for aging populations. We thus conducted a cross-sectional study in Zhejiang Province to assess this burden, identify its influencing factors, and explore hospitalization determinants, providing evidence for targeted pertussis control. Methods The research object from three prefecture-level cities (Hangzhou, Jiaxing, Jinhua) in Zhejiang Province, selected via stratified sampling based on gross domestic product (GDP). Data on sociodemographics, clinical features, and expenditures were collected via the China Infectious Disease Surveillance System, hospital information systems (HIS), and structured questionnaires. Economic burden was categorized as direct (medical/non-medical) and indirect (productivity loss). Statistical analyses included gamma distribution fitting (for right-skewed burden data), generalized linear models (GLM) for burden factors, and logistic regression for hospitalization determinants (SPSS 27.0). Results 195 respondents were enrolled (response rate: 81.3%), the total economic burden was 1,366,260 Renminbi (RMB), with a per-case mean of 7,007 RMB (median: 1,819 RMB, IQR: 653–9,234 RMB). Direct costs accounted for 75.9%, dominated by medical expenses (69.3%), while indirect costs contributed 24.1%. Inpatients had a 13.6-fold higher burden than outpatients (median: 11,026 vs. 811 RMB, P  < 0.001) .Multivariate GLM identified case type (Inpatients vs. outpatients, OR = 11.97, P  < 0.001) was the strongest independent predictor of total economic burden, and the hospitalization rate reached 40.5%. Logistic regression revealed high-risk groups for hospitalization: rural residents ( OR = 3.08, P  = 0.012), elderly males (advanced age: OR = 1.15, P  < 0.001; male: OR = 2.80, P  = 0.015), and patients with complications ( OR = 2.94, P  = 0.045).Additionally, fever was both increases total economic burden and hospitalization rate ( OR = 1.32/4.11, P  < 0.05), the same with onset-to-diagnosis interval ( OR = 1.02/1.04, P  < 0.05). Conclusion Older adults with pertussis in Zhejiang Province face substantial economic burden, characterized by a prominent hospitalization-driven pattern and high hospitalization rate. Targeted interventions—shortening the onset-to-diagnosis interval, optimizing outpatient care for high-risk groups (elderly males, rural residents, febrile cases), reducing complications and unnecessary hospitalizations, and advancing immunization strategy research—may effectively alleviate this burden.