Cheng Nai-Ming, Sy Cheng Len, Chen Bao-Chen, Huang Tsi-Shu, Lee Susan Shin-Jung, Chen Yao-Shen
Division of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
Division of Microbiology, Department of Pathology and Laboratory Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
PLoS Negl Trop Dis. 2017 Apr 5;11(4):e0005520. doi: 10.1371/journal.pntd.0005520. eCollection 2017 Apr.
Dengue fever is an important arboviral disease. The clinical manifestations vary from a mild non-specific febrile syndrome to severe life-threatening illness. The virus can usually be detected in the blood during the early stages of the disease. Dengue virus has also been found in isolated cases in the cerebrospinal fluid, urine, nasopharyngeal sections and saliva. In this report, we describe the isolation of dengue virus from the upper respiratory tract of four confirmed cases of dengue.
We reviewed all laboratory reports of the isolation of dengue virus from respiratory specimens at the clinical microbiology laboratory of the Kaohsiung Veterans General Hospital during 2007 to 2015. We then examined the medical records of the cases from whom the virus was isolated to determine their demographic characteristics, family contacts, clinical signs and symptoms, course of illness and laboratory findings.
Dengue virus was identified in four patients from a nasopharyngeal or throat culture. Two were classified as group A dengue (dengue without warning signs), one as group B (dengue with warning signs) and one as group C (severe dengue). All had respiratory symptoms. Half had family members with similar respiratory symptoms during the period of their illnesses. All of the patients recovered uneventfully.
The isolation of dengue virus from respiratory specimens of patients with cough, rhinorrhea and nasal congestion, although rare, raises the possibility that the virus is capable of transmission by the aerosol route among close contacts. This concept is supported by studies that show that the virus can replicate in cultures of respiratory epithelium and can be transmitted through mucocutaneous exposure to blood from infected patients. However, current evidence is insufficient to prove the hypothesis of transmission through the respiratory route. Further studies will be needed to determine the frequency of respiratory colonization, viable virus titers in respiratory secretions and molecular genetic evidence of transmission among close contacts.
登革热是一种重要的虫媒病毒病。其临床表现从轻度非特异性发热综合征到严重的危及生命的疾病不等。在疾病早期通常可在血液中检测到该病毒。在个别病例的脑脊液、尿液、鼻咽部切片和唾液中也发现了登革病毒。在本报告中，我们描述了从4例确诊登革热病例的上呼吸道中分离出登革病毒的情况。
我们查阅了高雄荣民总医院临床微生物实验室2007年至2015年期间从呼吸道标本中分离登革病毒的所有实验室报告。然后检查分离出病毒的病例的病历，以确定其人口统计学特征、家庭接触者、临床体征和症状、病程及实验室检查结果。
从鼻咽或咽喉培养物中鉴定出4例登革病毒。2例归类为A组登革热（无预警体征的登革热），1例为B组（有预警体征的登革热），1例为C组（重症登革热）。所有患者均有呼吸道症状。半数患者在患病期间有家庭成员出现类似呼吸道症状。所有患者均顺利康复。
从咳嗽、流涕和鼻塞患者的呼吸道标本中分离出登革病毒，尽管罕见，但增加了该病毒通过气溶胶途径在密切接触者之间传播的可能性。这一概念得到了一些研究的支持，这些研究表明该病毒可在呼吸道上皮细胞培养物中复制，并可通过黏膜皮肤接触感染患者的血液传播。然而，目前的证据不足以证明通过呼吸道途径传播这一假说。需要进一步研究以确定呼吸道定植的频率、呼吸道分泌物中的活病毒滴度以及密切接触者之间传播的分子遗传学证据。
