Laboratory of Virology, Department of Molecular Medicine, Sapienza University of Rome, Viale di Porta Tiburtina 28, 00185, Rome, Italy.
Med Microbiol Immunol. 2012 Aug;201(3):311-7. doi: 10.1007/s00430-012-0233-6. Epub 2012 Mar 10.
The relationship between viral load, disease severity and antiviral immune activation in infants suffering from respiratory syncytial virus (RSV)-associated bronchiolitis has not been well identified. The main objective of this study was to determine the existence of a correlation between RSV load and disease severity and also between different clinical markers and mRNA levels of the interferon stimulated gene (ISG)56 in infants hospitalized for bronchiolitis. We also evaluated whether viral load tended to be persistent over the course of the RSV infection. The levels of RSV-RNA were quantified in nasopharyngeal washings, collected from 132 infants infected with RSV as a single (90.15%) or as a dual infection with other respiratory viruses (9.85%). Results indicated that viral load was positively related to the clinical severity of bronchiolitis, the length of hospital stay, the levels of glycemia and the relative gene expression of ISG56, whereas an inverse correlation was observed with the levels of hemoglobin. We also found that the RSV load significantly decreased between the first and second nasopharingeal washings sample in most subjects. These results suggest that infants with high RSV load on hospital admission are more likely to have both more severe bronchiolitis and a higher airway activation of antiviral immune response.
病毒载量、疾病严重程度与呼吸道合胞病毒（RSV）相关毛细支气管炎患儿抗病毒免疫激活之间的关系尚未明确。本研究的主要目的是确定 RSV 载量与疾病严重程度之间，以及不同临床标志物与 IFN 刺激基因（ISG）56mRNA 水平之间是否存在相关性，这些患儿因毛细支气管炎住院。我们还评估了病毒载量是否倾向于在 RSV 感染过程中持续存在。从 132 例 RSV 单一感染（90.15%）或与其他呼吸道病毒双重感染（9.85%）的婴儿中收集鼻咽冲洗液，定量检测 RSV-RNA。结果表明，病毒载量与毛细支气管炎的临床严重程度、住院时间、血糖水平和 ISG56 的相对基因表达呈正相关，而与血红蛋白水平呈负相关。我们还发现，在大多数研究对象中，RSV 载量在第一次和第二次鼻咽冲洗样本之间显著降低。这些结果表明，入院时 RSV 载量较高的婴儿更有可能出现严重的毛细支气管炎和更高的气道抗病毒免疫反应激活。
