Viral load of respiratory syncytial virus among children from primary care and hospital settings admitted to a university hospital in Brazil (2009‐2013)

Abstract

Respiratory syncytial virus (RSV) is a relevant cause of acute respiratory infection among children. Viral replication and immune conditions may account for severity. RSV viral load (VL) was assessed in 486 children (290 hospitalized and 196 from primary care) attended at São Paulo Hospital from 2009 to 2013. VL was calculated by real‐time reverse transcription‐polymerase chain reaction and expressed in Log10 RNA copies/mL. Coinfection with rhinovirus (RV) and influenza A virus was also tested. Young children (<1 year of age) had a higher mean VL than older children at primary care (6.35 and 4.34 Log10 RNA copies/mL, respectively; P = .0006). Conversely, hospitalized children ≥2 years of age, presented higher mean VL compared with the same age children of primary care (6.10 and 4.26, respectively; P = .0024). RV was the most codetected virus in RSV positive patients (20% from primary care and 14% in hospitalized), and influenza A virus was found in 11% of primary care and 0.4% in hospitalized children with RSV, without RSV VL association (P = .2903). These findings may guide future therapies and immunization policies considering the role of viral load on clinical presentation among older hospitalized children and also the change of infection transmissions.

Association of viral load with TRAIL, IP‐10, CRP biomarker signature and disease severity in children with respiratory tract infection or fever without source: A prospective, multicentre cohort study

“…However, differences between viruses may be plausible in light of the discrepant baseline demographics such as age and diagnosis, with FLU patients being substantially older and presenting with FWS more frequently than RSV patients. Similarly, we did not investigate viral codetections, for which conflicting results had been reported, [29][30][31][32] partly explained by competitive interplays between different viruses such as RSV and HRV. 33 In addition, our cohort consists of non-ICU patients, which limits the inference regarding very severe cases.…”

Role of Viral Load and Host Cytokines in Determining the Disease Severity of Respiratory Syncytial Virus-Associated Acute Lower Respiratory Tract Infections in Children

“…The quantum of direct cytopathic effects exerted by RSV on respiratory epithelium might depend on the viral load (4), however, it is still under speculation because of contradictory findings (5)(6)(7). The Th1 cytokines are needed for viral clearance but an overwhelming secretion of pro-inflammatory cytokines like IL-6 and TNFα cause recruitment of neutrophils that damage the respiratory epithelium (8).…”

“…Positive correlation of TNFα & IL-10 (r = 0.464, p <0.001), TNFα & IL-6 (r= 0.360, p <0.001), TNFα & MMP-9 (r =0.208, p <0.05) and IL-10 & IL-6 (r = 0.468 p <0.001) cytokines and inverse correlation of MMP-9 & IFN-Ƴ (r = -0.352, p <0.01) was observed with severe ALRTI patients.DiscussionAn early recognition of disease progression, based on specific biomarkers rather than subjective scoring systems, is imperative to decrease the morbidity and mortality associated with RSV. The association of viral load with disease severity remained controversial (25-27).Haddadin et al 2020(5) and Cruz et al 2020(6) have reported a positive correlation with disease severity whereas Vianna et al 2021(7) documented that viral load had no relation with severity of disease. Our data suggested that viral load does not have any significant variation with the age or requirement for intensive care management, however, it was a marker for transition from non-severe to severe ALRTI.…”

Sinais e sintomas de manifestações orais e cutâneas em crianças com COVID-19: revisão narrativa

“…Nos países em desenvolvimento as doenças agudas do trato respiratório inferior constituem importante causa de internação hospitalar de crianças com idade inferior a cinco anos (Gralinski & Baric, 2015). Na maioria das vezes, tem como etiologia viral como por exemplo o vírus respiratório sincicial, seguido do parainfluenza, influenza e adenovírus (Cruz, de Souza Luna, Alves, Conte, & Bellei, 2021;Zhu et al, 2021).…”