Respiratory viral infection can cause severe disease and hospitalization, especially among children, the elderly, and patients with comorbidities. In Brazil, official surveillance system of severe acute respiratory infection (SARI) investigates influenza A (IAV) and B (IBV) viruses, respiratory syncytial virus (RSV), adenovirus (HAdV), parainfluenza viruses (hPIV). In Rio Grande do Sul (RS), Brazil, many fatalities associated with SARI between 2013-2017 were patients without underlying diseases and for whom the causative agent had not been identified using official protocols.
This cross-sectional study analyzed the presence of coronaviruses (HCoV), bocavirus (HBoV), metapneumovirus (hMPV), rhinovirus in patients who died of SARI despite not having comorbidities, and that were negative for IAV, IBV, RSV, HAdV, hPIV. Nasopharyngeal aspirates/swabs from patients were used for nucleic acid extraction. The presence of HCoV OC43, HKU1, NL63, and 229E; HBoV; hMPV; and rhinovirus was assessed by RT-qPCR. Clinical data was also analyzed.
Between 2013 and 2017, 16,225 cases of SARI were reported in RS; 9.8% of the patients died; 20% of all fatal cases were patients without comorbidities and for whom no pathogen was detected using standard protocols. Analysis of 271 of these cases identified HCoV in nine cases; HBoV, hMPV, and rhinovirus were detected in three, three, and ten cases, respectively. Of note, patients infected with HCoV were adults.
Results reinforce the importance of including coronaviruses in diagnostic panels used by official surveillance systems because, besides their pandemic potential, endemic HCoVs are associated to severe disease in healthy adults. This article is protected by copyright. All rights reserved.

This article is protected by copyright. All rights reserved.