Molecular detection of NSP-5 and its relation with mi-RNA from patient infected with Rotavirus in Baghdad City

Background: Vaccination is still the only effective way to prevent acute diarrhea in children under five, which is primarily caused by rotavirus. It is essential to look into virus-host interactions and find new biomarkers for early diagnosis in the absence of targeted treatments. The relationship between rotavirus infection and microRNA-7 (miR-7) expression is investigated in this work. Methods: 130 stool samples from children with acute gastroenteritis under the age of five were gathered. A commercial rapid antigen test was first used to screen for rotavirus infection, yielding 27 positive and 103 negative samples. All samples had their total RNA extracted, and RT-qPCR was used to measure the expression levels of miR-7, using miR-16 as an endogenous control. Receiver Operating Characteristic (ROC) curve analysis was used to evaluate miR-7's diagnostic performance. Additionally, the rotavirus NSP5 and NSP3 genes were found in a subset of samples using traditional RT-PCR. Findings: In stools from the rapid-test-positive group (n = 27) compared to the negative disease-control group (n = 103), MiR-7 expression was significantly upregulated (p < 0.0001). MiR-7 has a high diagnostic accuracy for differentiating these groups, according to ROC curve analysis, with an area under the curve (AUC) of 0.965, 85% sensitivity, and 99% specificity at an ideal cut-off of 5.83-fold change. Our particular RT-PCR assays detected the NSP5 gene in only 4 samples (3.1%) and the NSP3 gene in 1 sample (0.76%), despite the rapid test showing a positivity rate of 20.8%. This suggests a significant discrepancy that is probably caused by high primer specificity for specific rotavirus strains that are not prevalent in our cohort. Conclusion: Children with gastroenteritis who test positive for rotavirus using a rapid antigen test have significantly higher levels of fecal miR-7. In this situation, it exhibits high diagnostic accuracy. It is a promising non-invasive biomarker due to its stability in stool. Future research employing more comprehensive molecular confirmation techniques (such as RT-qPCR targeting conserved genes) is necessary to conclusively establish miR-7's specificity for rotavirus infection, as the low confirmation rate by our particular RT-PCR assays indicates the association is with the rapid test status.