1
|
He J, Ma Q, Teng Z, Zhou J, Zhao N, Liang W, Lu M, Li S, Qin T. Epidemiological and clinical characteristics of scrub typhus in Guizhou Province, China: An outbreak study of scrub typhus. PLoS Negl Trop Dis 2024; 18:e0011963. [PMID: 38442086 PMCID: PMC10914282 DOI: 10.1371/journal.pntd.0011963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Accepted: 02/02/2024] [Indexed: 03/07/2024] Open
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.
Collapse
Affiliation(s)
- Jia He
- National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People’s Republic of China
| | - Qing Ma
- Guizhou Center for Disease Control and Prevention, Guizhou, People’s Republic of China
| | - Zhongqiu Teng
- National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People’s Republic of China
| | - Jingzhu Zhou
- Guizhou Center for Disease Control and Prevention, Guizhou, People’s Republic of China
| | - Na Zhao
- National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People’s Republic of China
| | - Wenqin Liang
- Guizhou Center for Disease Control and Prevention, Guizhou, People’s Republic of China
| | - Miao Lu
- National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People’s Republic of China
| | - Shijun Li
- Guizhou Center for Disease Control and Prevention, Guizhou, People’s Republic of China
| | - Tian Qin
- National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People’s Republic of China
| |
Collapse
|
2
|
Thiriot JD, Liang Y, Gonzales C, Sun J, Yu X, Soong L. Differential cellular immune responses against Orientia tsutsugamushi Karp and Gilliam strains following acute infection in mice. PLoS Negl Trop Dis 2023; 17:e0011445. [PMID: 38091346 PMCID: PMC10752558 DOI: 10.1371/journal.pntd.0011445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 12/27/2023] [Accepted: 12/06/2023] [Indexed: 12/28/2023] Open
Abstract
Scrub typhus is a leading cause of febrile illness in endemic countries due to infection with Orientia tsutsugamushi (Ot), a seriously understudied intracellular bacterium. Pulmonary involvement associated with vascular parasitism in patients is common and can develop into life threatening interstitial pneumonia. The diverse antigenicity of Ot genotypes and inter-strain differences in genome content are connected to varied virulence and clinical outcomes; however, detailed studies of strain-related pulmonary immune responses in human patients or small animal models of infection are lacking. In this study, we have used two clinically prevalent bacterial strains (Karp and Gilliam) to reveal cellular immune responses in inflamed lungs and potential biomarkers of disease severity. The results demonstrate that outbred CD-1 mice are highly susceptible to both Karp and Gilliam strains; however, C57BL/6 (B6) mice were susceptible to Karp, but resistant to Gilliam (with self-limiting infection), corresponding to their tissue bacterial burdens and lung pathological changes. Multicolor flow cytometric analyses of perfused B6 mouse lungs revealed robust and sustained influx and activation of innate immune cells (macrophages, neutrophils, and NK cells), followed by CD4+ and CD8+ T cells, during Karp infection, but such responses were greatly attenuated during Gilliam infection. The robust cellular responses in Karp-infected B6 mice positively correlated with significantly early and high levels of serum cytokine/chemokine protein levels (CXCL1, CCL2/3/5, and G-CSF), as well as pulmonary gene expression (Cxcl1/2, Ccl2/3/4, and Ifng). In vitro infection of B6 mouse-derived primary macrophages also revealed bacterial strain-dependent immune gene expression profiles. This study provided the lines of evidence that highlighted differential tissue cellular responses against Karp vs. Gilliam infection, offering a framework for future investigation of Ot strain-related mechanisms of disease pathogenesis vs. infection control.
Collapse
Affiliation(s)
- Joseph D. Thiriot
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Yuejin Liang
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Casey Gonzales
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Jiaren Sun
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, Texas, United States of America
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Xiaoying Yu
- Department of Biostatistics & Data Science, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Lynn Soong
- Department of Microbiology & Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Institute for Human Infection and Immunity, University of Texas Medical Branch, Galveston, Texas, United States of America
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| |
Collapse
|