Viruses as Sole Causative Agents of Severe Acute Respiratory Tract Infections in Children

Abstract

BackgroundRespiratory syncytial virus (RSV) and influenza A viruses are known to cause severe acute respiratory tract infections (SARIs) in children. For other viruses like human rhinoviruses (HRVs) this is less well established. Viral or bacterial co-infections are often considered essential for severe manifestations of these virus infections.ObjectiveThe study aims at identifying viruses that may cause SARI in children in the absence of viral and bacterial co-infections, at identifying disease characteristics associated with these single virus infections, and at identifying a possible correlation between viral loads and disease severities.Study DesignBetween April 2007 and March 2012, we identified children (<18 year) with or without a medical history, admitted to our paediatric intensive care unit (PICU) with SARI or to the medium care (MC) with an acute respiratory tract infection (ARTI) (controls). Data were extracted from the clinical and laboratory databases of our tertiary care paediatric hospital. Patient specimens were tested for fifteen respiratory viruses with real-time reverse transcriptase PCR assays and we selected patients with a single virus infection only. Typical bacterial co-infections were considered unlikely to have contributed to the PICU or MC admission based on C-reactive protein-levels or bacteriological test results if performed.ResultsWe identified 44 patients admitted to PICU with SARI and 40 patients admitted to MC with ARTI. Twelve viruses were associated with SARI, ten of which were also associated with ARTI in the absence of typical bacterial and viral co-infections, with RSV and HRV being the most frequent causes. Viral loads were not different between PICU-SARI patients and MC-ARTI patients.ConclusionBoth SARI and ARTI may be caused by single viral pathogens in previously healthy children as well as in children with a medical history. No relationship between viral load and disease severity was identified.

Comparison of viral and epidemiological profiles of hospitalized children with severe acute respiratory infection in Beijing and Shanghai, China

“…In addition, several factors may account for this disparity, including true differences in the overall burden or differences in study populations or methodologies [18,[23][24][25]. Moreover, infection rates vary with geographical location and season [22,26,27]. Finally, the specific viruses included in our screening decisions may account for the higher positive rates in our study.…”

Clinical characteristics and outcomes of patients with severe acute respiratory infections (SARI): results from the Egyptian surveillance study 2010–2014

“…Previous studies showed conflicting results on the impacts of viral infections on clinical outcomes in patients with SARI [9,13,14,19,22,23]. Differences in patients' numbers, enrollment criteria, and methodologies could explain these results.…”

Epidemiology of human respiratory viruses in children with acute respiratory tract infection in a 3-year hospital-based survey in Northern Italy

“…In this scenario, superinfection exclusion mechanisms preventing a secondary infection with the same or a closely related virus should be envisaged (Folimonova, 2012). Although mixed infections have been widely assessed in ARTIs (Moesker et al, 2016;Seo et al, 2014;Turner et al, 2013), there is still no clear relationship with prolonged virus shedding, asymptomatic virus persistence, and disease severity. However, there is evidence that genome quantification could clarify the role of each virus in mixed infections (Franz et al, 2010;Martin et al, 2012).…”