Beck-Friis Thomas, Kärmander Ambjörn, Nyström Kristina, Wang Hao, Gisslén Magnus, Andersson Lars-Magnus, Norder Heléne
Department of Infectious Diseases, Region Västra Götaland, Sahlgrenska University Hospital, Gothenburg, Sweden.
Department of Infectious Diseases, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Gut Pathog. 2022 Aug 20;14(1):35. doi: 10.1186/s13099-022-00509-w.
Little is known of possible selection and replication of SARS-CoV-2 in the intestines and if viral load in feces is associated with severity of disease. Therefore, sequence variations of the spike region in strains collected from feces and nasopharynx (NPH) from the same patients were compared. It was also investigated whether viral load in feces related to severity of COVID-19 in hospitalized patients.
SARS-CoV-2 RNA was found in 88 (79%) fecal samples from 112 patients. The complete spike region could be sequenced in 15 fecal and 14 NPH samples. Fourteen Alpha-variants and one Beta-variant of SARS-CoV-2 were identified. The majority of the viral genetic variants (viral populations) in two fecal samples, but none in NPH, had a reversion of the H69/V70 amino acid deletion normally seen in the Alpha variants. Nine fecal samples contained up to nine minority variants, each which may constitute a separate viral population. Five NPH samples had one genetic variant each, and one NPH sample contained nine minority populations of SARS-CoV-2 spike genes.
The higher genomic diversity of SARS-CoV-2 in feces compared to NPH, and the reversion of the H69/V70 deletion in Alpha variants from feces indicate a selection of viral strains and replication of SARS-CoV-2 in the gastrointestinal tract.
关于严重急性呼吸综合征冠状病毒2（SARS-CoV-2）在肠道中可能的选择和复制情况，以及粪便中的病毒载量是否与疾病严重程度相关，目前所知甚少。因此，对从同一患者粪便和鼻咽（NPH）采集的毒株中刺突区域的序列变异进行了比较。还研究了住院患者粪便中的病毒载量是否与新型冠状病毒肺炎（COVID-19）的严重程度相关。
在112例患者的88份（79%）粪便样本中发现了SARS-CoV-2 RNA。15份粪便样本和14份鼻咽样本中可对完整的刺突区域进行测序。鉴定出14个SARS-CoV-2的α变异株和1个β变异株。两份粪便样本中的大多数病毒基因变异体（病毒群体），但鼻咽样本中均未出现通常在α变异株中可见的H69/V70氨基酸缺失的回复突变。9份粪便样本中含有多达9个少数变异体，每个变异体可能构成一个单独的病毒群体。5份鼻咽样本各有一个基因变异体，1份鼻咽样本包含SARS-CoV-2刺突基因的9个少数群体。
与鼻咽样本相比，SARS-CoV-2在粪便中的基因组多样性更高，且粪便中α变异株的H69/V70缺失回复突变表明在胃肠道中存在病毒株的选择和SARS-CoV-2的复制。
