Institute of Clinical Infectious Diseases, Catholic University of Sacred Heart, Rome, Italy.
J Med Virol. 2011 Dec;83(12):2057-65. doi: 10.1002/jmv.22231.
Since several characteristics of pandemic influenza A (H1N1) virus infection remain to be determined, this study aimed to describe clinical features and complications of patients infected with H1N1. Subjects affected by influenza-like illnesses and a control group of asymptomatic patients were enrolled prospectively at an Emergency Department from October 2009 to April 2010. At enrollment, clinical data and nasopharyngeal swabs for virological analyses were obtained. Ill subjects were followed until recovery and swabs were collected weekly in patients infected with H1N1. Of 318 patients enrolled, 92 (28.9%) were positive to H1N1. Patients infected with H1N1 were mainly young adults and complained classic influenza-like symptoms. Fever was observed for a median time of 5 (IQR 3-7) days. Hospitalization occurred in 27.7% with 2% requiring intensive care unit admission: median length of hospitalization was 6 days (IQR 5-9). Pneumonia was diagnosed in 19.6% of patients. A similar proportion of lower airways involvement and of clinical complications was observed in subjects testing positive or negative for H1N1. However, patients infected with H1N1 were younger and hospitalized for a shorter period as compared to the control group (P = 0.002 and P = 0.045, respectively). Older age, asthma/chronic obstructive pulmonary disease and hypertension were associated with an increased risk of pneumonia. Viral shedding was observed for at least 1 week in 21.3% of patients. Asymptomatic infection was uncommon (1.1%). Respiratory syndromes caused by H1N1 and factors associated with disease severity were investigated and compared to influenza-like illnesses of other origin. Such findings might contribute to improve clinical and epidemiological management of the disease.
由于大流行性流感 A（H1N1）病毒感染的一些特征仍有待确定，本研究旨在描述感染 H1N1 的患者的临床特征和并发症。2009 年 10 月至 2010 年 4 月，在一家急诊科前瞻性地招募了患有流感样疾病的受试者和无症状患者对照组。入组时，获取临床数据和鼻咽拭子进行病毒学分析。对有症状的患者进行随访，直至康复，对感染 H1N1 的患者每周采集一次拭子。在纳入的 318 例患者中，92 例（28.9%）对 H1N1 呈阳性。感染 H1N1 的患者主要是年轻成年人，表现出典型的流感样症状。发热中位数持续时间为 5 天（IQR 3-7）。住院率为 27.7%，2%需要入住重症监护病房：中位住院时间为 6 天（IQR 5-9）。肺炎在 19.6%的患者中被诊断。在 H1N1 检测阳性或阴性的患者中，下呼吸道受累和临床并发症的比例相似。然而，与对照组相比，感染 H1N1 的患者更年轻，住院时间更短（P = 0.002 和 P = 0.045）。年龄较大、哮喘/慢性阻塞性肺疾病和高血压与肺炎风险增加相关。21.3%的患者至少观察到 1 周的病毒脱落。无症状感染罕见（1.1%）。研究了由 H1N1 引起的呼吸道综合征和与疾病严重程度相关的因素，并与其他来源的流感样疾病进行了比较。这些发现可能有助于改善疾病的临床和流行病学管理。
