Abstract:

Objective To understand the epidemic characteristics of scrub typhus in Nanshan District of Shenzhen City for evidence to formulate and improve prevention and control measures for this infectious disease. Methods The reported cases of scrub typhus in Nanshan District from 2011 to 2021 were collected through the China Information System for Disease Control and Prevention, and described regarding the three-dimensional distribution of the disease, mode of medical treatment, clinical symptoms of the infection and exposure patterns. The spatiotemporal scanning analysis method was used to analyze the spatiotemporal aggregation. Results In total, 181 cases of scrub typhus were reported in Nanshan District from 2011 to 2021. Annual reported incidence rate was 1.08/100 000, ranging from 0.58/100 000 to 2.28/100 000. The infection primarily occurred from May to November (91.16%, 165/181). Of the reported cases, 100 were males, and 81 females, with sex ratio being 1.23∶1. The population aged 40-49 (26.52%, 48/181) were most affected (27.83%, 47/181). By occupations, workers were most involved (28.73%, 52/181). 60.77% (110/181) of patients preferred to seek medical attention from a general hospital during onset of the disease, and 51.38% (93/181) were diagnosed with scrub typhus at the first visit. The main symptoms of the infection were fever (100.00%, 181/181), specific eschar or ulcer (97.79%, 177/181), and headache (65.19%, 118/181). The top three exposure modes were outdoor walking (43.65%, 79/181), outdoor work (29.28%, 53/181), and sitting and lying on grass (22.65%, 41/181). The epidemic focus was mainly involved in the block of Zhaoshang, Xili and Nantou (78.45%, 142/181). Spatiotemporal scanning indicated that Wenzhuyuan community in Zhaoshang block was Ⅰ-level clustering area from 2017 to 2019. Conclusion Scrub typhus appears sporadic in Nanshan District, for which the measures, including active vector monitoring and prevention, strengthening health education for the population and improving the diagnosis and treatment level of scrub typhus among clinical medical personnel, are recommended.

Key words: Scrub typhus, Epidemiological characteristics, Spatiotemporal clustering, Nanshan District