长沙市妇幼保健院352例孕产妇新型冠状病毒感染临床及分子流行病学特征研究

Clinical and molecular epidemiological characteristics of SARS-CoV-2 infection in 352 pregnant and postpartum women at Changsha Maternal and Child Health Hospital

目的 了解湖南省长沙市妇幼保健院孕产妇群体中新型冠状病毒(简称新冠病毒)感染后临床特征和新生儿结局,并分析新型冠状病毒的分子流行病学特征。方法 收集2022年12月8日至2023年1月7日长沙市妇幼保健院的孕产妇和新生儿临床资料和鼻咽拭子样本。对新型冠状病毒核酸阳性样本采用Nanopore三代测序进行新冠病毒全基因组测序。使用Nextclade网站进行新冠病毒序列分型和比对分析。使用MEGA X软件进行进化树构建,方法为邻接法。结果 共收治孕产妇993例,其中新冠病毒核酸检测阳性352例,占35.45%。感染高发期为2022年12月20日,阳性率为93.75%(30/32)。孕产妇年龄为(30.6±4.05)岁。实际住院天数为(3.88±2.41) d。共获得341份病例临床症状资料,其中81.52%(278/341)出现发热,67.74%(231/341)出现咳嗽,49.85%(170/341)出现咽痛,其余症状为乏力、肌痛和头痛等。有3.23%(11/341)出现腹泻症状。2例孕产妇出现重症肺炎,但经转院治疗后治愈出院。326例新冠病毒阳性产妇所生新生儿无重症肺炎症状,但新生儿核酸检测阳性率为3.37%(11/326),早产率为10.43%(34/326)。孕产妇和新生儿均未出现死亡病例,且预后良好。经全基因组测序分析,获得的8份毒株序列主要为BA. 5.2分支,进化树分析显示序列分布于多个亚分支,存在多条传播链。核苷酸位点分析结果显示,毒株与武汉参考株相比存在75~77个核苷酸突变位点,序列同源性为99.6%。氨基酸序列分析结果显示突变位点发生在ORF1a、ORF1b、ORF7a和S基因中,其中S基因新突变位点为S371Y、T883I和D1146Y,未发现重组毒株。结论 长沙市妇幼保健院孕产妇和新生儿人群未出现严重新冠病毒感染临床病例。新冠病毒流行亚型为常见病毒亚型。

Objective To understand the clinical characteristics and neonatal outcomes of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection among pregnant and postpartum women at Changsha Mater-nal and Child Health Hospital,Hunan province,and to analyze the molecular epidemiological characteristics of SARS-CoV-2.Methods The clinical data of pregnant women and newborns with a positive nucleic acid test of SARS-CoV-2 in Changsha Maternal and Child Health Hospital from December 8,2022 to January 7,2023 were collected.Whole-genome sequencing of SARS-CoV-2 was performed on positive samples using Nanopore third-generation sequencing.Sequence typing and comparative analysis were performed using the Nextclade website,and the phylogenetic tree was constructed using the neighbor-joining method by MEGA X software.Results A total of 993 pregnant women were treated in this study,of which 352 were positive for SARS-CoV-2,accounting for 35.45%.The peak incidence period was December 20,2022,with a positive rate of 93.75%(30/32).The average age of the infected women was(30.6±4.05)years old,and the average hospital stay was(3.88±2.41)days.A total of 341 cases of clinical symptoms were obtained,of which 81.52%(278/341)had a fever,67.74%(231/341)had a cough,and 49.85%(170/341)reported sore throat.Other symptoms included fatigue,myalgia,and headache,with 3.23%(11/341)exhibiting diarrhea.Two cases of severe pneumonia were treated successfully after transfer to specialized hospital.Among 326 SARS-CoV-2-positive pregnant women cases,there was no severe pneumonia,but the positive rate of the neonatal nucleic acid test was 3.37%(11/326),with a preterm birth rate of 10.43%(34/326).No maternal and neonatal deaths occurred,and the prognosis was good.The whole genome sequencing analysis showed that the eight strains were mainly in the BA.5.2 lineage,with phylogenetic analysis indicating distribution across multiple sub-branches and several transmission chains.Nucleotide site analysis showed 75-77 nucleotide mutation sites compared with the Wuhan reference strain,with a sequence homology of 99.6%.Amino acid sequence analysis showed that the mutation sites occurred in ORFla,ORF1b,ORF7a,and the S genes,including new mutation S371Y,T883I and D1146Y,and no recombinant strains were detected.Conclusion Clinical severe cases are not found among the pregnant and postpartum population at Changsha Maternal and Child Health Hospital,and the popular subtypes are common.