Epidemiological and clinical characteristics of scrub typhus in Guizhou Province, China: An outbreak study of scrub typhus

PLoS Negl Trop Dis. 2024 Mar 5;18(3):e0011963. doi: 10.1371/journal.pntd.0011963. eCollection 2024 Mar.

Abstract

The reported cases of scrub typhus (ST) have continued to escalate, with outbreaks occurring regionally in China. These pose an increasing public health threat at a time when public health has been overwhelmed. During the period from July to August 2022, in Rongjiang County, Guizhou Province, China, 13 out of 21 fever patients were diagnosed with scrub typhus, based on epidemiological investigation and blood test analysis. The major clinical symptoms of these patients showed fever, chills, headache, eschar, fatigue and pneumonia, which were accompanied by a rise in C-reactive protein, neutrophils, alanine transaminase (ALT) and aspartate aminotransferase (AST). Furthermore, nearly half of them exhibited abnormal electrocardiogram activity. Through semi-nested PCR, Sanger sequencing and phylogenetic tree construction, the Karp strain of Orientia tsutsugamushi (O. tsutsugamushi) was confirmed as the pathogen causing ST in Rongjiang County, which shared the same evolutionary branch with O. tsutsugamushi isolated from wild mouse liver or spleen, indicating that the wild mouse plays an important role in transmitting the disease. In contrast to the sporadic cases in the past, our study is the first to disclose an epidemic and the corresponding clinical characteristics of ST in Guizhou province, which is of great significance for the prevention and treatment of regional illnesses.

MeSH terms

  • Animals
  • China / epidemiology
  • Disease Outbreaks
  • Fever
  • Humans
  • Mice
  • Phylogeny
  • Public Health
  • Scrub Typhus* / epidemiology

Grants and funding

This work was supported by the Science Foundation for the State Key Laboratory for Infectious Disease Prevention and Control from China under Grant number 2022SKLID209 (awarded to TQ) and 2019SKLID403 (awarded to TQ), the Public Health Service Capability Improvement Project of the National Health Commission of the People’s Republic of China under Grant number 2100409002 (awarded to TQ) and the National Key Research and Development Program of China under Grant number 2021YFC2301202 (awarded to TQ). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.