AUTHOR=Lu Huixiu , Li Jianying , Fan Rong , Hao Gaoyuan , Sun Meilan , Liang Yunchuan 

TITLE=First laboratory-confirmed case of scrub typhus in Shijiazhuang City, Hebei Province

JOURNAL=Frontiers in Microbiology

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2024.1409949

DOI=10.3389/fmicb.2024.1409949

ISSN=1664-302X

ABSTRACT=<sec><title>Objective</title><p>Defining whether a suspected case was due to scrub typhus through laboratory testing, to understand the prevalence of scrub typhus in Shijiazhuang City, Hebei Province.</p></sec><sec><title>Methods</title><p>An epidemiological investigation was conducted on the suspected case, utilizing Weil-Felix test and indirect immunofluorescence assay (IFA) to detect specific antibodies against <italic>O. tsutsugamushi</italic> in serum specimens. Additionally, PCR amplification of the 56-kDa and <italic>groEL</italic> genes was performed, followed by constructing a phylogenetic tree to identify the genotype.</p></sec><sec><title>Results</title><p>The acute phase titer of the Weil-Felix test for the case was 1:160, which increased to 1:320 in the recovery phase. IFA assay revealed IgG titers against <italic>O. tsutsugamushi</italic> of 1:64 in the acute phase and 1:256 in the recovery phase. Sequence alignment of the PCR amplified fragment showed the highest similarity with the <italic>O. tsutsugamushi</italic> genotype. Kawasaki sequence, ranging from 99.71 to 100.00%. The strain exhibited the closest genetic relationship with the known <italic>O. tsutsugamushi</italic> Kawasaki genotype.</p></sec><sec><title>Conclusion</title><p>This study confirms the presence of <italic>O. tsutsugamushi</italic> in Shijiazhuang City, Hebei Province, with the identified strain belonging to the Kawasaki genotype, marking the first diagnosis of this strain in the region.</p></sec>