Clinical and Epidemiologic Characteristics of Hospitalized Patients with Laboratory-Confirmed Respiratory Syncytial Virus Infection in Eastern China between 2009 and 2013: A Retrospective Study

Abstract

Respiratory syncytial virus (RSV) is a leading cause of morbidity and mortality worldwide in children aged <5 years and older adults with acute lower respiratory infections (ALRIs). However, few studies regarding the epidemiology of hospitalizations for RSV infection have been performed previously in China. Here, we aimed to describe the clinical and epidemiologic characteristics of hospitalized patients with laboratory-confirmed RSV infection in eastern China. Active surveillance for hospitalized ALRI patients using a broad case definition based on symptoms was performed from 2009-2013 in 12 sentinel hospitals in eastern China. Clinical and epidemiologic data pertaining to hospitalized patients of all ages with laboratory-confirmed RSV infection by PCR assay were collected and analyzed in this study. From 2009 to 2013, 1046 hospitalized patients with laboratory-confirmed RSV infection were enrolled in this study, and 14.7% of patients had subtype A, 24.2% of patients had subtype B, 23.8% of patients with subtype not performed, and 37.3% of patients had RSV coinfections with other viruses. RSV and influenza coinfections (33.3%) were the most common coinfections noted in this study. Moreover, young children aged <5 years (89.1%, 932/1046), particularly young infants aged <1 year (43.3%, 453/1046), represented the highest proportion of patients with RSV infections. In contrast, older adults aged ≥60 years (1.1%, 12/1046) represented the lowest proportion of patients with RSV infections among enrolled patients. The peak RSV infection period occurred mainly during autumn and winter, and 57% and 66% of patients exhibited symptoms such as fever (body temperature ≥38°C) and cough separately. Additionally, only a small number of patients were treated with broad-spectrum antiviral drugs, and most of patients were treated with antimicrobial drugs that were not appropriate for RSV infection. RSV is a leading viral pathogen and a common cause of viral infection in young children aged <5 years with ALRIs in eastern China. Effective vaccines and antiviral agents targeting RSV are needed to mitigate its large public health impact.

Fig 1. Locations of the 12 sentinel hospitals in eastern China at which respiratory syncytial virus (RSV) patients were treated.

The red numbers indicate the locations of the surveillance sites. A total of 12 sentinel hospitals located in six provinces were enrolled in the final RSV infection analysis. 1). Children's Hospital of Shanghai, Shanghai Jiao Tong University; 2). Children’s Hospital of Fudan University; 3). Huzhou Central Hospital, Zhejiang Province; 4). The First Affiliated Hospital, School of Medicine, Zhejiang University; 5). The Children’s Hospital, School of Medicine, Zhejiang University; 6). Zhejiang Provincial Center for Disease Control and Prevention; 7). Renmin Hospital of Wuhan University; 8). Tongji Hospital, Tongji Medical College, Huazhong University of Science & Technology; 9). Wuhan Women and Children Medical Care Center, Hubei Province; 10). Jiangxi Provincial Children’s Hospital; 11). Maternal and Children's Health Hospital of Fujian Province; 12). Hunan Provincial People’s Hospital.

Fig 2. Patients with laboratory-confirmed RSV infection.

(A) Distributions of RSV subtypes and coinfections among 1046 patients. (B) Distributions of other viral infections among 390 patients with RSV coinfections. *Others indicated RSV+HBoV+RV, RSV+EV, RSV+CoV, or RSV+HMPV, as less than 13 cases of each were noted. HPIV, human parainfluenza virus; HBoV, human bocavirus; AdV, adenovirus; RV, rhinovirus; CoV, coronavirus; HMPV, human metapneumovirus; EV, enterovirus.

Fig 3. Seasonal trends of laboratory-confirmed RSV infection in hospitalized patients in eastern China between 2009 and 2013.

(A) RSV infection; (B) RSV-A; (C) RSV-B; (D) Subtyping not performed; (E) Coinfection with other viruses.