在苏格兰,每年平均有1976名儿童以毛细支气管炎为主要诊断而住院。[3]ISD Scotland. Number of hospital discharges with bronchiolitis in children 0-24 months in Scotland for the years ending December 2001-2003 [statistical data]. Edinburgh: ISD Scotland 2006. 毛细支气管炎是婴幼儿最常罹患的疾病,也是该年龄阶段患儿住院的主要原因。[4]Deshpande SA, Northern V. The clinical and health economic burden of respiratory syncytial virus disease among children under 2 years of age in a defined geographical area. Arch Dis Child. 2003 Dec;88(12):1065-9.http://www.ncbi.nlm.nih.gov/pubmed/14670770?tool=bestpractice.com 大约每30名婴幼儿中会有1名婴幼儿在1周岁内罹患毛细支气管炎。[5]Shay DK, Holman RC, Newman RD, et al. Bronchiolitis-associated hospitalizations among US children, 1980-1996. JAMA. 1999 Oct 20;282(15):1440-6.https://jamanetwork.com/journals/jama/fullarticle/192009http://www.ncbi.nlm.nih.gov/pubmed/10535434?tool=bestpractice.com
2015 年,全球 5 岁以下儿童呼吸道合胞体病毒 (respiratory syncytial virus, RSV) 导致的急性下呼吸道感染 (acute lower respiratory infection, ALRI) 估计为 3310 万例(不确定性范围 [UR] 21.6-50.3),导致约 320 万名 (UR 2.7-3.8) 患者入院,住院死亡人数为 59,600 (UR 48,000-74,500)。在 6 月龄以下的儿童中,由于 RSV-ALRI,140 万名 (UR 1.2-1.7) 患者入院和 27,300 (UR 20,700-36,200) 例院内死亡。[6]Shi T, McAllister DA, O'Brien KL, et al. Global, regional, and national disease burden estimates of acute lower respiratory infections due to respiratory syncytial virus in young children in 2015: a systematic review and modelling study. Lancet. 2017 Sep 2;390(10098):946-58.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5592248/http://www.ncbi.nlm.nih.gov/pubmed/28689664?tool=bestpractice.com 毛细支气管炎的发病率呈现明显的季节性,在美国大多数病例发生在11月至5月。[7]Ralston SL, Lieberthal AS, Meissner HC, et al; American Academy of Pediatrics. Clinical practice guideline: the diagnosis, management, and prevention of bronchiolitis. Pediatrics. 2014 Nov;134(5):e1474-502.http://pediatrics.aappublications.org/content/134/5/e1474.longhttp://www.ncbi.nlm.nih.gov/pubmed/25349312?tool=bestpractice.com 疾病的发病高峰通常发生在1月或2月。 在东南部,疾病的发病和高峰略早。 其他温带地区一般表现出类似的年度隆冬流行模式。 相反,副流感病毒1感染(引起哮吼)表现为两年一度的发病模式。
毛细支气管炎几乎完全是一种婴幼儿疾病,基本上所有3岁以下的孩子都有被RSV感染的血清学证据。 然而,婴儿中RSV的主要感染并没有获得保护性免疫,所以重复感染是很常见的。 尽管对于大多数婴儿,疾病是轻度和自限性的,但该病可能发展严重,尤其是6个月以下的婴儿。[8]Hall CB, Weinberg GA, Iwane MK, et al. The burden of respiratory syncytial virus infection in young children. N Engl J Med. 2009 Feb 5;360(6):588-98.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4829966/http://www.ncbi.nlm.nih.gov/pubmed/19196675?tool=bestpractice.com 有潜在严重感染危险因素(如早产、先天性心脏病或慢性肺部疾病)的婴幼儿住院风险更大,但大多数住院婴儿没有潜在的危险因素。
除了毛细支气管炎的急性反应,研究还表明,大部分罹患 RSV 毛细支气管炎的婴幼儿可进展为复发性喘息;[9]Mansbach JM, Camargo CA Jr. Respiratory viruses in bronchiolitis and their link to recurrent wheezing and asthma. Clin Lab Med. 2009 Dec;29(4):741-55.http://www.ncbi.nlm.nih.gov/pubmed/19892232?tool=bestpractice.com 鼻病毒已经得到越来越多的研究,并且研究结果发现鼻病毒与复发性喘息和哮喘的诊断有关。[10]Jackson DJ, Gangnon RE, Evans MD, et al. Wheezing rhinovirus illnesses in early life predict asthma development in high-risk children. Am J Respir Crit Care Med. 2008;178:667-72.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2556448/http://www.ncbi.nlm.nih.gov/pubmed/18565953?tool=bestpractice.com[11]Lukkarinen M, Koistinen A, Turunen R, et al. Rhinovirus-induced first wheezing episode predicts atopic but not nonatopic asthma at school age. J Allergy Clin Immunol. 2017 Oct;140(4):988-95.http://www.ncbi.nlm.nih.gov/pubmed/28347734?tool=bestpractice.com[12]Törmänen S, Lauhkonen E, Riikonen R, et al. Risk factors for asthma after infant bronchiolitis. Allergy. 2018 Apr;73(4):916-22.http://www.ncbi.nlm.nih.gov/pubmed/29105099?tool=bestpractice.com[13]Midulla F, Nicolai A, Ferrara M, et al. Recurrent wheezing 36 months after bronchiolitis is associated with rhinovirus infections and blood eosinophilia. Acta Paediatr. 2014 Oct;103(10):1094-9.http://www.ncbi.nlm.nih.gov/pubmed/24948158?tool=bestpractice.com 哮喘家族史等危险因素会增加未来哮喘诊断的风险。[10]Jackson DJ, Gangnon RE, Evans MD, et al. Wheezing rhinovirus illnesses in early life predict asthma development in high-risk children. Am J Respir Crit Care Med. 2008;178:667-72.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2556448/http://www.ncbi.nlm.nih.gov/pubmed/18565953?tool=bestpractice.com[14]Brandão HV, Vieira GO, Vieira TO, et al. Acute viral bronchiolitis and risk of asthma in schoolchildren: analysis of a Brazilian newborn cohort. J Pediatr (Rio J). 2017 May - Jun;93(3):223-9.https://www.sciencedirect.com/science/article/pii/S002175571630119X?via%3Dihubhttp://www.ncbi.nlm.nih.gov/pubmed/27665269?tool=bestpractice.com