Objective To investigate the epidemiology of viral infection in elderly patients to contract acute exacerbations of chronic obstructive pulmonary disease (AECOPD)in Minhang district of Shanghai from 2010 to 2012,and to study the relationships between viral infection and clinical features.Methods The elderly patients (age >70 year old)with AECOPD admitted from September 2010 to November 2012 were enrolled for study.The patients who couldn't complete lung function test were excluded.The pharyngeal swabs (PS)were taken from each patient within the first 24 h after admission.Nine respiratory viruses and their subtypes from pharyngeal swabs were detected by the nested multiplex polymerase chain reaction (PCR)method,including influenza virus A (FluA),2009 influenza A (H1N1 )virus (09FluH1 ), influenza virus B (FluB),respiratory syncytial virus A (RSVA)and B (RSVB),human coronavirus-229E (hCOV-229E),human coronavirus-NL63 (hCOV-NL63 ),human coronavirus-OC43 (hCOV-OC43 ), human coronavirus-HKU1 (hCOV-HKU1),human parainfluenza virus 1-4 (hPIV1-4),human adenovirus (hAdV),human boca virus (hBoV),human metapneumo-virus (hMPV)and human rhinovirus (hRV). According to the PCR results,all patients were divided into positive viral infection group and negative viral infection group.The relationships between viral infection and clinical features were analyzed.Results Sixty patients were eligible for study.Of them,14 patients were found to be positive for virus infection including a triple infected patient (FluB,hRV and hROV)and 46 patients were negative for virus infection.The viral pathogens detected in the positive viral group were:9 cases of hRV (15.00%),2 cases of hPIV (3.33%),2 cases of hCOV (3.33%),2 cases of FluB (3.33%)and 1 cases of RSV (1.67%).The mortality in the positive viral group was higher than that in the negative viral group.However,the other clinical characteristics between the two groups had no significant differences. Conclusions Human rhinovirus was the most common viral pathogen in elderly patients with AECOPD.Viral infection might be associated with the prognosis.However,the patients with viral infection are lack of specific clinical characteristics,therefore,the prompt diagnosis before careful study would be difficult.