HFMD outbreak clusters in Beijing decreased by 74.4% during 2020-2022, rebounded in 2023, and are forecasted by a SARIMA model to reach 716 clusters with a bimodal seasonal pattern in 2025.
Observational (n=12,396)
HFMD outbreak clusters in Beijing show a biennial pattern that rebounded significantly post-COVID-19, highlighting the need for targeted interventions in schools and near-suburban areas.
Hand, foot, and mouth disease (HFMD) is a common enteric infectious disease that poses a threat to children’s health. The disease exhibits high epidemic intensity and frequent outbreak clusters in Beijing, the capital of China. However, the spatiotemporal characteristics of these outbreak clusters and their future epidemic trends remain poorly understood. This study aims to fill this gap by analyzing the spatiotemporal epidemiology of HFMD outbreak clusters and developing a forecasting model to inform targeted prevention strategies. The present study analyzed data on HFMD outbreak clusters in Beijing from 2019 to 2024. Epidemiological characteristics were described, including demographic features, clinical manifestations, transmission settings, and spatial distribution. Group comparisons were performed using Kruskal-Wallis and chi-squared tests. The spatial distribution of outbreak clusters was visualized and analyzed by geographic region. A Seasonal Autoregressive Integrated Moving Average (SARIMA) model was developed to forecast incidence trends. Beijing reported 4,265 HFMD outbreak clusters (12,396 cases) during 2019–2024, exhibiting a biennial high-incidence pattern. Compared to 2019 (1,206 clusters), the mean annual clusters during 2020–2022 decreased by 74.4% (305/year), rebounding to 1,719 clusters in 2023—42.5% higher than 2019. Most clusters (77.2%) involved 50% in multiple years). CV-A6 was dominant (60.2%), peaking at 90.7% in 2023; EV-A71 was rare (0.12%). Cluster size varied by pathogen (p < 0.001). The SARIMA model forecast a bimodal pattern for 2025, with primary autumn peak (299 clusters) and secondary summer peak (165 clusters). HFMD outbreak clusters in Beijing exhibited a biennial pattern, with suppression during 2020–2022 due to COVID-19 NPIs followed by a rebound in 2023 exceeding pre-pandemic levels. Clusters concentrated in near-suburban areas with consistent bimodal seasonality, and the SARIMA model projects a similar pattern for 2025. These findings underscore the need for setting-specific strategies prioritizing schools alongside kindergartens, targeted interventions in high-risk suburbs, and continued pathogen monitoring.
Zhao et al. (Thu,) conducted a observational in Hand, foot, and mouth disease (HFMD) (n=12,396). HFMD outbreak clusters in Beijing decreased by 74.4% during 2020-2022, rebounded in 2023, and are forecasted by a SARIMA model to reach 716 clusters with a bimodal seasonal pattern in 2025.