Molecular epidemiology of rhinovirus strains circulating in Belém, Pará State, Brazil

Abstract

Human rhinovirus (HRV) is the most common viral agent associated with infections of the upper respiratory tract and is the main causative agent of the common cold. This study aimed to detect and characterize HRV strains associated with severe acute respiratory syndrome (SARS) in Belém, Pará State, Brazil, by analyzing samples from 224 SARS patients admitted to hospitals between January 2013 and January 2014. Sample analysis was performed in three stages: (a) viral RNA isolation (vRNA); (b) amplification of vRNA using conventional and real-time reverse transcription polymerase chain reaction; and (c) viral genome sequencing. Among the 224 analyzed samples, 59 (26.3%) were HRV-positive, of which 22 HRV species could be characterized through sequencing. Thirteen (59%) were classified as HRV-A and eight (36.3%) as HRV-C; one sample was classified as human enterovirus D68 (EV-D68). Distribution by age revealed that adults were the most affected by HRV, accounting for 45.7% (n = 27) of total positive cases. There was an increased number of HRV-positive cases in the 0-4-year-old group (n = 23, 39%) during the study period. Relating to monthly HRV distribution in Belém, circulation was predominant during the first semester, which is typically associated with increased rainfall. The results indicate a high HRV infection rate; thus indicating that the pathogen is an important agent of respiratory infections in Belém.