Hii Shirley Yi Fen, Mohd Zaidi Maswani Nabilah, Kassim Wan Norazanin, Hashim Rohaidah, Ramli Siti Roszilawati
Bacteriology Unit, Infectious Diseases Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health Malaysia, Persiaran Setia Murni, Setia Alam, 40170 Shah Alam, Selangor, Malaysia.
Trop Med Infect Dis. 2025 Sep 2;10(9):252. doi: 10.3390/tropicalmed10090252.
Scrub typhus is caused by Gram-negative bacteria, . Humans are the dead-end host of scrub typhus. Currently, there is no vaccine available. The disease can be fatal without appropriate treatment. Here, we present the circulating OT genotypes in Malaysia and a -based single PCR to detect and determine OT genotypes, which is an approach to replace the time-consuming traditional nested PCR. The patients' blood or tissue samples ( = 1200), received from all hospitals in Malaysia from December 2022 to November 2024, were screened for rickettsial infections. Both A qPCR and nested PCR were performed to detect the presence of OT DNA. Simultaneously, a selection of DNA was evaluated for the new single PCR protocol and confirmed with Sanger sequencing. We report that Pahang state of Peninsular Malaysia presents the highest number of acute scrub typhus infections in Malaysia within the 24 months period. There are four genotypes circulating in the Malaysian population. OT genotype Gilliam ( = 31, 29.2%) and Karp ( = 31, 29.2%) are the predominant OT genotypes in Malaysia, followed by TA763 ( = 22, 20.8%) and Kato ( = 22, 20.8%). The single-run PCR presents longer sequence size and similar results with the nested PCR. Acute scrub typhus infection is not rare in Malaysia and should be considered for undifferentiated febrile illness. The single-run PCR protocol is time-saving and a promising approach for OT detection and genotype analysis in a single run to complement a clinical diagnostic setting and surveillance.
恙虫病由革兰氏阴性细菌引起。人类是恙虫病的终末宿主。目前尚无可用疫苗。若不进行适当治疗，该疾病可能致命。在此，我们展示了马来西亚的恙虫病东方体（OT）基因型以及一种基于[具体技术]的单重PCR方法，用于检测和确定OT基因型，这是一种取代耗时的传统巢式PCR的方法。对2022年12月至2024年11月期间从马来西亚所有医院收集的患者血液或组织样本（n = 1200）进行立克次体感染筛查。同时进行定量PCR（qPCR）和巢式PCR以检测OT DNA的存在。同时，对一部分DNA进行新单重PCR方案评估并用桑格测序法进行确认。我们报告，在这24个月期间，马来西亚半岛的彭亨州急性恙虫病感染病例数最多。马来西亚人群中有四种基因型流行。OT基因型吉列姆型（n = 31，29.2%）和卡尔普型（n = 31，29.2%）是马来西亚主要的OT基因型，其次是TA763型（n = 22，20.8%）和加藤型（n = 22，20.8%）。单重PCR呈现出更长的序列长度且结果与巢式PCR相似。急性恙虫病感染在马来西亚并不罕见，对于未分化的发热性疾病应予以考虑。单重PCR方案省时，是一种很有前景的单次检测OT并进行基因型分析的方法，可作为临床诊断和监测的补充。
