Human coronavirus ocurrence in different populations of Sao Paulo: A comprehensive nine-year study using a pancoronavirus RT-PCR assay

Human coronaviruses (HCoVs) are considered one of the most common respiratory viruses associated with respiratory tract illnesses. An emergent human coronavirus was identified as the causal agent of an epidemic of severe acute respiratory syndrome (SARS) during 2002–2003. The severity of the disease combined with its rapid spread requires the continuous surveillance of coronaviruses in worldwide populations. Epidemiological and clinical data of HCoVs infectious in the Brazilian population are scarce and restricted to one or two groups of patients. Our study aimed to investigate retrospectively the presence of HCoVs in different populations of São Paulo presenting acute respiratory tract infections (ARIs) during the years of 2001–2010. A pancoronavirus RT-PCR was performed in this study. Coronaviruses were detected in 126 (11.5%) of 1,087 specimens. Peaks detection frequency was observed during 2002–2004 and 2008–2009, with the highest detection in 2008. The prevalence of HCoVs was higher among children with heart diseases (24.6%), patients under stem cell transplantation program (24.3%) and renal transplanted patients (20.2%). Coryza, cough and fever were the most common symptoms at presentation of positive cases and wheezing, a lower respiratory tract infection symptom was reported by 12% of the total, and 27% of high at-risk patients. HCoVs may have an important role among patients with underlying conditions and transplanted ones.