Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan.
Department of Viral and Rickettsial Diseases, Infectious Diseases Directorate, Naval Medical Research Center, Silver Spring, Maryland.
Vector Borne Zoonotic Dis. 2019 Nov;19(11):821-827. doi: 10.1089/vbz.2018.2426. Epub 2019 Aug 13.
is an obligate intracellular bacterium that causes scrub typhus in humans. Formerly thought to be confined to the "tsutsugamushi triangle" within the Asia-Pacific region, scrub typhus was recently identified in the Western Hemisphere. Moreover, a new species of bacterial genus was isolated from a patient in Dubai. This study investigated exposure in an African country, the Democratic Republic of Sao Tome and Principe. Two sets of samples were analyzed in the study: 240 dried blood spots (DBSs) collected in 2016 and 863 serum samples from 570 pregnant women in 2003. Antibodies against were examined by immunofluorescence assay (IFA) and enzyme-linked immunosorbent assay (ELISA). The positive samples were further confirmed by Western blot. The results of IFA showed that 5.8% (14/240) of DBSs and 20.4% (116/570) of the serum samples contained reactive antibodies, whereas IgG ELISA yielded a positive rate of 15.4% (88/570) for the serum samples. These findings provided serologic evidence of potential exposure even though case of scrub typhus has never been diagnosed in the nation. Further studies are needed to determine the epidemiology and the burden of this neglected tropical disease in Africa.
是一种专性细胞内细菌，可引起人类丛林斑疹伤寒。以前认为这种疾病只局限于亚太地区的“恙虫病三角区”，但最近在西半球也发现了丛林斑疹伤寒。此外，从迪拜的一名患者身上分离出了一种新的细菌属。本研究调查了非洲国家圣多美和普林西比民主共和国的暴露情况。本研究分析了两组样本：2016 年采集的 240 份干血斑（DBS）和 2003 年 570 名孕妇的 863 份血清样本。通过免疫荧光分析（IFA）和酶联免疫吸附试验（ELISA）检测针对 的抗体。IFA 阳性的样本进一步通过 Western blot 进行确认。IFA 的结果显示，240 份 DBS 中有 5.8%（14/240）和 570 份血清样本中有 20.4%（116/570）含有反应性抗体，而 IgG ELISA 对血清样本的阳性率为 15.4%（88/570）。这些发现提供了针对 的潜在暴露的血清学证据，尽管该国有从未诊断过丛林斑疹伤寒的病例。需要进一步研究以确定这种被忽视的热带病在非洲的流行病学和负担。
