High genetic diversity of human rhinovirus among pilgrims with acute respiratory tract infections during the 2019 Hajj pilgrimage season

Objectives: Acute respiratory tract infections (ARIs) due to human rhinoviruses (HRVs) are common in pilgrims during the annual Hajj pilgrimage. The objective of this study was to investigate the genetic diversity of HRV among pilgrims with respiratory symptoms during Hajj 2019. Methods: HRV infection was detected using multiplex real-time reverse transcription polymerase chain reaction. Cycle sequencing was performed on positive samples and the sequences were subjected to phylogenetic analysis. Results: A total of 19 HRV-positive respiratory samples were sequenced. All three serotypes of HRV were identified: HRV-A (13; 68.42%) was more common than HRV-B (2; 10.53%) and HRV-C (4; 21.05%). HRV-A species were found to be of genotypes A101, A21, A30, A57, A23, A60, and A11. HRV-B species belonged to genotypes B4 and B84, and HRV-C species were of genotypes C15, C3, and C56. Conclusion: Sequencing studies of respiratory tract viruses in pilgrims are important. We provide preliminary evidence of high diversity of HRV genotypes circulating in pilgrims in a restricted area during Hajj. This requires further clinical and sequencing studies of viral pathogens in larger cohorts of overseas and local pilgrims.