ABSTRACT
Objective: Coronavirus disease 2019 (COVID-19), leading to mild infection (MI), acute respiratory distress syndrome or death in different persons. Although the basis of these variabilities has not been fully elucidated, some possible findings have been encountered. In the present study, we aimed to reveal genes with different expression profiles by next-generation sequencing of RNA isolated from blood taken from infected patients to reveal molecular causes of different response. Methods: Two healthy, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-negative control individuals (NCI), two SARS-CoV-2-positive patients who have MI, and two patients who have critical infection (CI) were included in the study. Total RNA was extracted from blood samples and sequenced. Raw RNA-Seq data were analyzed on Galaxy platform for the identification of differentially expressed genes and their pathway involvements. Results: We found that 199 and 521 genes were downregulated in whole blood of COVID-19-positive CI patients compared to NCI and MI patients, respectively. We identified 21 gene ontology pathways commonly downregulated in CI patients compared to both NCI and MI, mostly associated with innate and adaptive immune responses. Three hundred and fifty-four and 600 genes were found to be upregulated compared to NCI and MI, respectively. Upregulated six pathways included genes that function in inflammatory response and inflammatory cytokine release. Conclusion: The transcriptional profile of CI patients deviates more significantly from that of MI in terms of the number of differentially expressed genes, implying that genotypic differences may account for the severity of SARS-CoV-2 infection and inflammatory responses through differential regulation of gene expression. Therefore, further studies that involve whole genome analysis coupled with differential expression analysis are required in order to determine the dynamics of genotype - gene expression profile associations.
ABSTRACT
OBJECTIVES/HYPOTHESIS: The emergence of a new coronavirus strain (SARS-CoV-2) in December 2019 from China led to a global pandemic. The lack of herd immunity against this virus and the possibility of viral spread from asymptomatic individuals is still a major challenge for the prevention of viral transmission. The aim of this study was to evaluate the presence of the virus in different bodily secretions as a potential source of viral spread among patients infected with SARS-CoV-2. STUDY DESIGN: Cross Sectional Study. METHODS: The study included 38 COVID-19 patients with a positive real-time polymerase chain reaction (RT-PCR) test result for SARS-CoV-2, obtained from the combined nasopharyngeal-oropharyngeal swab samples. Saliva, tear, and cerumen samples were taken from the patients within 72 hours of the first RT-PCR test. SARS-CoV-2 N1 and N2 gene regions were studied with single-step RT-PCR in all samples. RESULTS: Among the studied samples, the highest positivity rate was in saliva (76.3%) followed by tears (55.3%) and cerumen (39.5%). Viral load in saliva was also significantly higher compared to tears and cerumen (P < .001), while there was no significant difference between tears and cerumen. Higher viral load in combined nasopharyngeal-oropharyngeal swab samples was associated with higher viral load in tears, but not in saliva or cerumen. Half of the saliva, tear, and cerumen samples obtained from asymptomatic patients contained SARS-CoV-2 genome. CONCLUSIONS: The virus was detected in the saliva, tears, and cerumen samples of both symptomatic and asymptomatic patients. The potential role of these bodily fluids on viral spread needs to be studied. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E1677-E1682, 2021.