<p>Genomic and Phenotypic Diversity of <em>Listeria monocytogenes</em> Causing Pregnancy-Associated Listeriosis from Zhejiang Province, China, 2016–2018</p>

Abstract

Introduction: There are few investigations describing the pregnancy-associated listeriosis in China, and the molecular characteristics of Listeria monocytogenes causing such infections remain largely unknown. We aim to investigate the phenotypic and genomic profiles of pregnancy-associated L. monocytogenes isolates and their association with isolates recovered from human and non-human in China. Materials and Methods: In this study, we conducted a 3-year surveillance of listeriosis in a women's hospital in Zhejiang province, using whole genome sequencing and bioinformatics tools. Results: From 2016 to 2018, we identified 13 clinical L. monocytogenes isolates. Among these pregnancy-associated isolates, we found seven sequence types (STs), with the prevalent STs of ST87 and ST7. Serotyping divided the strains into four serotypes, including serotype 1/2a, 1/2b, 3a, and 4b. Antimicrobial resistance testing showed that all the isolates were susceptible to 10 antibiotics. Comparative genomics analysis clearly classified our genome collection into four distinct evolutionary lineages with most isolates grouping into lineages I and II. Interestingly, we found three pairs of isolates with high identity, although no evident epidemiological association was observed. Conclusion: This study reports for the first time the surveillance of pregnancy-associated listeriosis in Zhejiang province, China, which indicates that the infection rate is low in this region. Our findings provide insight into the evolution and genetic diversity of pregnancyassociated L. monocytogenes from Zhejiang province. Additional investigations involving more human and non-human isolates with a "one health" strategy are needed for prediction of the listeriosis risk associated with a typical prevalent clone in Zhejiang province, such as ST87.

An Update Review on Listeria Infection in Pregnancy

“… 29 However, in most LM infections reported in Europe and many other nations, including China, just four types (1/2a, 1/2b, 1/2c, and 4b) give rise to clinical LM infection. 30 Serological-type 4b has the strongest virulence, and could even cause a pandemic in humans, although type 1/2a is most commonly discovered in consumables. 10 Compared to non-pregnant women, serotype 4b has a higher likelihood to infect pregnant women.…”

Genomic Characterization of a Clinical Listeria monocytogenes ST1 Isolate Recovered from the Blood Sample of a Woman with Third Trimester Stillbirth

“…16 Mirroring to the result of previous studies in our hospital, the most common STs in 12 cases of perinatal Listeria infection were ST87 (25.0%), ST7 (25%), and ST2 (16.7%). 9 One recent retrospective multi-center study highlighted ST87 (34.0%) was most prevalent in China, but the proportion of ST1 (12.5%) was not only abnormally second highest, but was also considered as a hypervirulent lineage, ie, increased invasiveness, intracellular replication and neurotropism of L. monocytogenes in ruminants. 18 Perinatal listeriosis is a rare infection caused by L. monocytogenes, whereas it has extremely high perinatal fatality.…”

“…7 The reports of clinical perinatal listeriosis in China were mostly limited to the summary of clinical cases, and there were few related studies on whole-genome sequencing for serological prediction and phylogenetic analysis of globally disseminated L. monocytogenes isolates. [7][8][9][10][11] In order to fill this gap, the genome of a L. monocytogenes isolate recovered from the blood specimen of a 30-week pregnant woman was sequenced, with the purpose of elucidating its genomic features and antibiotic resistance mechanisms.…”