Rhinovirus species and their clinical presentation among different risk groups of non-hospitalized patients.

Infections caused by Human Rhinoviruses (HRVs) account for 25-50% of respiratory illnesses among individuals presenting influenza-like illness (ILI). HRVs could be classified in at least three species: HRV-A, HRV-B, and HRV-C. The HRV-C species has frequently been described among children and has led to severe illness resulting in hospitalization; however, the occurrence among adults is unknown. The aim of this study was to assess the clinical presentation and species distribution of HRV infections in different populations during 2001-2008. A total of 770 samples were collected. Subjects consisted of 136 adults from the general community and 207 health-care workers (2001-2003), 232 renal-transplanted outpatients (2002-2004), 70 children with congenital heart disease (2005) and 125 children from a day-care center (2008). Amplification of HRV genes was performed by reverse transcriptase-polymerase chain reaction (RT-PCR) and followed by sequencing and phylogenetic analysis. HRV was detected in 27.4% of samples (211/770), with 72 children (36.9%) and 139 adults infected (24.2%). A total of 89.61% (138/154) unknown HRV strains were sequenced, and 79.22% (122/138) were analyzed. We identified 74 isolates (60.7%) of the HRV A species, 21 (17.2%) of the HRV B species and 27 isolates (22.1%) of the HRV C species. HRV species A and B caused ILI among adult patients, whereas HRV-C did not. The dynamics of infection among different species deserve further analysis.