Retrospective analysis of pregnancy-associated listeriosis in a city in southeastern China (Xiamen) from 2015 to 2023

Abstract

Background Pregnancy-associated listeriosis caused by foodborne infections poses a significant threat to maternal and neonatal health, with a high mortality rate. There is limited epidemiological data, and this study investigates the epidemiology and clinical features in Xiamen. Methods Retrospective analysis of confirmed cases of pregnancy-associated listeriosis in Xiamen from 2015 to 2023 was performed (southeastern China). Perform data analysis and epidemiological investigation on demographic information, clinical manifestations, laboratory tests, complications, and outcomes of pregnant women and their offspring, and antibacterial susceptibility test were conducted on all isolated Listeria monocytogenes (LM) using commercial reagent kits. Results In Xiamen, the incidence of pregnancy-associated listeriosis over nine years was 7.15/100,000 (9/125,816) deliveries, with a seasonal peak in spring and summer. Predominant clinical symptoms among pregnant women included fever (88.9%), abdominal pain (66.7%), decreased fetal movement (66.7%), fetal tachycardia (66.7%), and flu-like symptoms (55.6%). All affected pregnant women exhibited elevated neutrophil percentages (NE%), C-reactive protein (CRP), and procalcitonin (PCT). Placental pathology consistently showed acute chorioamnionitis and micro-abscesses. Although all pregnant women recovered, out of 10 offspring, only 5 survived birth, and merely 3 were eventually cured, resulting in a feto-neonatal mortality rate of 70.0% (7/10). All LM strains showed susceptibility to ampicillin, penicillin, meropenem, erythromycin, and trimethoprim-sulfamethoxazole (SXT). Conclusions Although rare in Xiamen, pregnancy-associated listeriosis underscores the critical need for enhanced food safety education for pregnant women. The disease's atypical clinical features necessitate prompt specimen testing upon suspicion of infection, highlighting the importance of awareness and timely medical intervention.