PubMedChina CDC weekly2026-10-17
Epidemiological Characteristics and Spatial Clustering of Single-Dog-Induced Multiple Human Exposure Events - Chongqing, China, 2016-2025.
Wu Weidong W, Lyu Shouming S, Ju Hao H, Li Tingting T et al.
Single-dog-induced multiple human exposure events can result in multiple potential rabies exposures within a short period, with substantial public health and economic costs. In China, these events are managed under nationally standardized procedures and require a coordinated public health and animal health response. This study analyzed the epidemiological characteristics, post-exposure prophylaxis (PEP), and response gaps associated with these events in Chongqing from 2016 to 2025.
Data on events, offending dogs, and exposed persons were collected from investigation reports submitted by district and county CDCs. Human rabies surveillance data for Chongqing were obtained from the China CDC Information System. Spearman correlation analysis was used to assess the association between annual event counts and the number of human rabies cases reported, and cross-correlation function (CCF) analysis was used to assess the temporally lagged association. Joinpoint regression was used to evaluate temporal trends, and global and local Moran's I statistics were used to assess spatial clustering. Statistical significance was defined as P<0.05.
A total of 124 events involving 649 exposed persons were reported, including 3 human rabies deaths. Annual event counts were positively correlated with the number of human rabies cases reported during the same period (r=0.782, P<0.01), and CCF analysis showed positive correlations across all lag months, with the correlation being strongest with a 2-month lag (r=0.426, 95% CI: 0.355, 0.629, P<0.001). The annual number of events declined during the study period (average annual percent change=-19.0%, P<0.01), with a rapid decline between 2016 and 2022 and a nonsignificant increase between 2022 and 2025. Most events (74.2%) occurred in rural areas. Spatial clustering was detected in 2016-2017, 2018-2019, and 2024-2025. Category III exposures accounted for 82.7% of exposed persons. Rabies vaccine coverage was 98.9%, and rabies immunoglobulin was administered to 87.5% of persons with Category III exposure. No deaths occurred among those who received standard PEP, whereas mortality was 2.6% among those who did not (P<0.01). Stray dogs accounted for 66.9% of offending dogs. Only 7 canine specimens were tested from the 124 offending dogs (5.6%), and all were positive for rabies virus antigen by direct fluorescent antibody test using brain tissue.
From 2016 to 2025, single-dog-induced multiple human rabies exposure events in Chongqing declined overall and showed localized clustering. Most events occurred in rural areas, with Category III exposures predominating. In this group, no deaths occurred among standardized PEP recipients, whereas 3 deaths occurred among individuals who did not receive standardized PEP. To reduce human rabies, event monitoring and standardized PEP should be strengthened.