title: Clinical and epidemiological features of the 2014 large-scale dengue outbreak in Guangzhou city, China.
abstract: BACKGROUND
  Dengue virus is transmitted by mosquito around the tropical and sub-tropical regions. There was a large-scale dengue epidemic in Guangdong province, China during 2014 and around fifty thousands dengue fever cases, including six deaths, have been reported. In this study, we aimed to understand the clinical characteristics of hospitalized patients with laboratory-confirmed dengue virus (DENV) infection and determined the origin of the virus from the outbreak.
  
  
  METHODS
  We have summarized the data from 138 hospitalized patients who were laboratory confirmed for dengue infection in Guangzhou city. Patients were classified as either non-severe dengue fever or severe dengue fever according to the guidelines from the WHO. Viral serotypes were determined by real time RT-PCR. Genetic sequences of the envelope and non-structural genes were amplified and analyzed from the serum samples of eleven patients.
  
  
  RESULTS
  Co-circulation of dengue serotype 1 and 2 were identified from the outbreak. Patients infected by serotype 1 or 2 showed similar clinical features. Patients with severe dengue fever showed prolonged hospitalization and significant impairment of organ functions. Four samples from serotype 1 and five samples from serotype 2 were closely related respectively and clustered with Guangzhou isolates from previous years. The remaining isolates of serotype 1 were related to viruses found in Malaysia, India, Bangladesh and Singapore.
  
  
  CONCLUSIONS
  The phylogenetic grouping of Guangdong isolates suggests that dengue is no longer an imported disease in China. Analysis of the isolates obtained in this study together with the size of the outbreak are suggestive of endemic circulation in Guangdong province.
authors.affiliation: Department of Laboratory Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangdong, China. lin_y_p@hotmail.com.|Research Centre of Translational Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangdong, China. lin_y_p@hotmail.com.
authors.forename: Yong Ping
authors.initials: YP
authors.lastname: Lin
authors.affiliation: Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangdong, China. yashalo715@126.com.|Department of Laboratory Medicine, Guangdong Women and Children Hospital, Guangzhou, China. yashalo715@126.com.
authors.forename: Yasha
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Department of Laboratory Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangdong, China. 249534077@qq.com.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: HKU-Pasteur Research Pole, School of Public Health, HKU Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China. m.lamers@erasmusmc.nl.
authors.forename: Mart Matthias
authors.initials: MM
authors.lastname: Lamers
authors.affiliation: Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangdong, China. 13631412228@163.com.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangdong, China. 673422349@qq.com.
authors.forename: Xiao Han
authors.initials: XH
authors.lastname: Yang
authors.affiliation: HKU-Pasteur Research Pole, School of Public Health, HKU Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China. sanyal@hku.hk.
authors.forename: Sumana
authors.initials: S
authors.lastname: Sanyal
authors.affiliation: HKU-Pasteur Research Pole, School of Public Health, HKU Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China. ch02mkp@hku.hk.
authors.forename: Chris Ka Pun
authors.initials: CK
authors.lastname: Mok
authors.affiliation: Department of Laboratory Medicine, The First Affiliated Hospital of Guangzhou Medical University, Guangdong, China. gylzm08@126.com.
authors.forename: Zhong Min
authors.initials: ZM
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D003715:Dengue / Q000175:diagnosis* / Q000453:epidemiology* / Q000821:virology; D003716:Dengue Virus / Q000235:genetics / Q000302:isolation & purification; D004196:Disease Outbreaks; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D065288:Serogroup; D014504:Urban Health / Q000706:statistics & numerical data*