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.

This study assessed the occurrence of human rhinovirus (HRV) species in outpatient children attending day-care in Sao Paulo, Brazil. HRV reverse transcriptase polymerase chain reaction and amplicon sequencing were done in 120 samples collected in 2008. HRV was detected in 27.5% of samples. HRV C was detected in 60.7% of wheezers, a frequency not different from that observed in nonwheezers (69.6%).

Although antibiotics are ineffective against viral respiratory infections, studies have shown high rates of prescriptions worldwide. We conducted a study in Brazil to determine the viral aetiologies of common colds in children and to describe the use of antibiotics for these patients. Children up to 12 years with common colds were enrolled from March 2008-February 2009 at a primary care level facility and followed by regular telephone calls and medical consultations. A nasopharyngeal wash was obtained at enrollment and studied by direct fluorescence assay and polymerase chain reaction for nine different types of virus. A sample of 134 patients was obtained, median age 2.9 years (0.1-11.2 y). Respiratory viruses were detected in 73.9% (99/134) with a coinfection rate of 30.3% (30/99). Rhinovirus was the most frequent virus (53/134; 39.6%), followed by influenza (33/134; 24.6%) and respiratory syncytial virus (8/134; 13.4%). Antibiotic prescription rate was 39.6% (53/134) and 69.8% (37/53) were considered inappropriate. Patients with influenza infection received antibiotics inappropriately in a greater proportion of cases when compared to respiratory syncytial virus and rhinovirus infections (p = 0.016). The rate of inappropriate use of antibiotics was very high and patients with influenza virus infection were prescribed antibiotics inappropriately in a greater proportion of cases.

Introduction: Influenza A H1N1 2009 is associated with a high morbidity rate among children around the world, including Brazil. This survey was conducted on samples of symptomatic children (≤ 12 years) to investigate the influenza virus as the etiological agent of respiratory infections in a day care school in a health facility during the first and second pandemic wave of H1N1 (2009)(2010) in São Paulo, Brazil. Methods: Influenza infections were determined by real-time PCR in 34% (47/137) of children with a median age of 5 years (8 months -12 years), from June to October 2009 and in 16% (14/85) of those with median age of 6 years (1-12 years), from March to November 2010. Results: In general, most positive cases (64%) occurred in children aged 5-12 years, this age group was significantly the most affected (39.8%, p = 0.001, OR = 8.3, CI 95% 1.9-36.9). Wheezing was reported by 31% (19/61) and dyspnea by 23% (14/61) of the studied patients. An outbreak of influenza H1N1 with an attack rate of 35.7% among children (median age 6 years) was documented in April 2010, before the vaccination campaign against the pandemic virus was extended for children up to 5 years in Brazil. Conclusions: Therefore, the study reinforces the recommendation to immunize school children to reduce the incidence of the disease.

To assess the occurrence and clinical aspects of respiratory viral infections in children with congenital heart disease in a cardiology pediatric ward a prospective study was done in children with acute respiratory infection during 2005, 2007 and 2008. Nasopharyngeal washes were collected and tested through direct immunofluorescence for human respiratory syncytial virus (HRSV), influenza virus A and B (Flu A/B), parainfluenzavirus 1, 2 and 3 (PIV 1,2,3) and human adenovirus (hAdV). Samples collected from hospitalized children were also evaluated for human metapneumovirus (hMPV), human rhinovirus (HRV) and human bocavirus (HBoV) through molecular methods. Out of 102 analyzed children, 11% were positive for the following viruses: 5 HRSV, 3 PIV-3, 1 Flu A, 1 Flu B, and 1 hAdV. Five (8,3%) of 60 patients needed hospitalization, and one of these patients died. These five patients had complex congenital heart disease, were not submitted to surgical correction and were under one year old. Three patients were positive for the following viruses: 1 HRSV, 1 HRV and 1 HRV+hAdV. The present study highlights the importance of respiratory viral infection in children with complex congenital heart disease morbidity. Other viral etiologies as HRV and hAdV, besides the common HRSV, should be considered in respiratory viral diagnosis.