Molecular and antigen detection, phylogenetics, and immunoinformatics study of the zoonotic coronavirus in Iranian diarrheic calves

Abstract

Background: Bovine coronaviruses (BCoVs) are zoonotic diseases that result in substantial economic losses due to mortality, impaired growth, and increased medication expenses in large animals. These viruses pose a risk to children who live beside infected animal, as they can cause diarrhea. This study was dedicated to molecular and antigen detections and phylogenetic and immunoinformatics analysis of zoonotic coronavirus (CoV) in Iran.Materials and Methods: A total of 77 diarrheic samples were collected from Holstein dairy herds in selected provinces of Iran. Samples were tested by capture antibody enzyme-linked immunosorbent assay (ELISA) to detect CoV and reverse transcriptase–polymerase chain reaction (RT–PCR) for verification of detection and also genotyping of spike glycoprotein in CoV-positive samples. After statistical analysis, nucleotide sequence alignment, and nucleotide and protein phylogenetic tree construction, the centralized sequence for vaccine strains was obtained using computationally optimized broadly reactive antigen (COBRA)'s center-of-the-tree (COT) method.Results: Twenty-two (28.5%) and eight (10.3%) of 77 samples were positive according to RT–PCR and ELISA, respectively. (Basic Local Alignment Search Tool) BLAST and phylogenetic analysis revealed that most similar sequences to the Iranian CoV sequence were for European countries. Furthermore, there were strong correlations to other CoVs in humans and wild and domesticated animals. As CoV has variable COT, the most recent strains and COBRA vaccine strains were obtained.Conclusion: Based on the high prevalence of this viral disease in calves and its economic impact on the breeding industry, as well as the potential transmission to humans and correlation with World Health Organization (WHO) One Health approach guidelines, the study emphasizes the importance of implementing preventive strategies such as animal vaccination.