Tramuto Fabio, Maida Carmelo Massimo, Di Naro Daniela, Randazzo Giulia, Vitale Francesco, Restivo Vincenzo, Costantino Claudio, Amodio Emanuele, Casuccio Alessandra, Graziano Giorgio, Immordino Palmira, Mazzucco Walter
Department of Health Promotion Sciences Maternal and Infant Care, Internal Medicine and Medical Specialties "G. D'Alessandro"-Hygiene Section, University of Palermo, 90127 Palermo, Italy.
Regional Reference Laboratory for Molecular Surveillance of Influenza, Clinical Epidemiology Unit, University Hospital "Paolo Giaccone", 90127 Palermo, Italy.
Vaccines (Basel). 2021 Nov 16;9(11):1334. doi: 10.3390/vaccines9111334.
Several respiratory pathogens are responsible for influenza-like illness (ILI) and severe respiratory infections (SARI), among which human respiratory syncytial virus (hRSV) represents one of the most common aetiologies. We analysed the hRSV prevalence among subjects with ILI or SARI during the five influenza seasons before the emergence of SARS-CoV-2 epidemic in Sicily (Italy). Respiratory specimens from ILI outpatients and SARI inpatients were collected in the framework of the Italian Network for the Influenza Surveillance and molecularly tested for hRSV-A and hRSV-B. Overall, 8.1% of patients resulted positive for hRSV. Prevalence peaked in the age-groups <5 years old (range: 17.6-19.1%) and ≥50 years old (range: 4.8-5.1%). While the two subgroups co-circulated throughout the study period, hRSV-B was slightly predominant over hRSV-A, except for the season 2019-2020 when hRSV-A strongly prevailed (82.9%). In the community setting, the distribution of hRSV subgroups was balanced (47.8% vs. 49.7% for hRSV-A and hRSV-B, respectively), while most infections identified in the hospital setting were caused by hRSV-B (69.5%); also, this latter one was more represented among hRSV cases with underlying diseases, as well as among those who developed a respiratory complication. The molecular surveillance of hRSV infections may provide a valuable insight into the epidemiological features of ILI/SARI. Our findings add new evidence to the existing knowledge on viral aetiology of ILI and SARI in support of public health strategies and may help to define high-risk categories that could benefit from currently available and future vaccines.
几种呼吸道病原体可导致流感样疾病（ILI）和严重呼吸道感染（SARI），其中人类呼吸道合胞病毒（hRSV）是最常见的病因之一。我们分析了在意大利西西里岛出现SARS-CoV-2疫情之前的五个流感季节中，ILI或SARI患者中的hRSV流行情况。在意大利流感监测网络的框架内，收集了ILI门诊患者和SARI住院患者的呼吸道标本，并对hRSV-A和hRSV-B进行了分子检测。总体而言，8.1%的患者hRSV检测呈阳性。患病率在<5岁年龄组（范围：17.6-19.1%）和≥50岁年龄组（范围：4.8-5.1%）达到峰值。在整个研究期间，这两个亚组共同流行，hRSV-B略多于hRSV-A，但在2019-2020季节hRSV-A占主导（82.�%）。在社区环境中，hRSV亚组的分布是平衡的（hRSV-A和hRSV-B分别为47.8%和49.7%），而在医院环境中发现的大多数感染是由hRSV-B引起的（69.5%）；此外，后者在有基础疾病的hRSV病例以及发生呼吸道并发症的病例中更为常见。hRSV感染的分子监测可为ILI/SARI的流行病学特征提供有价值的见解。我们的研究结果为ILI和SARI病毒病因的现有知识增添了新证据，以支持公共卫生策略，并可能有助于确定可从现有和未来疫苗中受益的高危类别。
