Objective To investigate the epidemic trends, key populations, and high-risk area characteristics of hand-foot-mouth disease (HFMD) in Ningbo from 2018 to 2023, and to provide evidence-based references for optimizing prevention strategies and precise allocation of prevention and control resources.

Methods Data on HFMD cases with current addresses in Ningbo from 2018 to 2023 were collected from the China Information System for Disease Control and Prevention. Descriptive epidemiological methods were used to analyze the epidemiological characteristics of HFMD. Global spatial autocorrelation analyses were applied to detect spatial clustering of HFMD, and spatiotemporal scan analyses were conducted to identify spatiotemporal clusters.

Results A total of 116 967 HFMD cases, were reported of which 2 were severe and none were fatal. The average annual incidence rate was 206.33 per 100 000 population, showing an overall declining trend. Seasonal patterns were observed, with bimodal distributions in 2018, 2019, 2021, and 2022 (main peak from May to July; secondary peak from September to November), and unimodal distributions in 2020 (peak from October to December) and 2023 (peak from July to October). Children aged 5 years and under accounted for the majority of cases (104 634 cases, 89.46%), with a mean age of (3.48±3.29) years. The male-to-female ratio was 1.44∶1. Children cared for at home (56.39%) and those attending kindergarten (35.97%) were the predominant populations. The highest average incidence rate was observed in Ninghai County (261.46/100 000), and the lowest in Fenghua District (152.46/100 000), while the average incidence rates in most districts/counties ranged from 188.22 to 226.53 per 100 000 population. The highest incidence rate was observed in areas classified as urban-rural fringes (240.08 per 100 000 population). Spatial analyses revealed global clustering in 2020 (Moran’s I=0.35, P<0.05), with hotspots concentrated in Ninghai county and Xiangshan county. Spatiotemporal scan analyses identified significant clusters each year from 2018 to 2023. The strongest cluster was detected in Cixi City from May to September in 2018 (LLR=27 249.53, RR=13.06, P<0.01), followed by Yinzhou District from April to October in 2019 (LLR=25 172.16, RR=10.61, P<0.01).

Conclusion The overall incidence of HFMD in Ningbo City shows a declining trend. The disease shows bimodal (spring-summer and autumn-winter) or unimodal (autumn-winter) seasonal patterns. Cases are predominantly seen in boys aged 5 years and under, and who are cared for at home or attend kindergarten、 High-risk areas are concentrated in southern counties (Ninghai and Xiangshan). It is recommended to strengthen health education and vaccination coverage for children aged 5 years and under, and to implement dynamic surveillance and targeted interventions in key areas during high-incidence seasons, so as to reduce transmission and spread.