title: The correlation between the presence of viremia and clinical severity in patients with enterovirus 71 infection: a multi-center cohort study.
abstract: BACKGROUND
  Enterovirus 71 (EV71) is a great disease burden across the whole world, particularly in Southeast Asia. However, in recent decades, the pathogenesis of severe EV71 infection was not well understood. This study was aimed to investigate the correlation between the presence of viremia and the clinical severity of EV71 infection.
  
  
  METHODS
  We organized a prospective cohort study and enrolled laboratory-confirmed EV71 cases in six tertiary care hospitals in Taiwan during the EV71 epidemic from 2011 to 2012. Blood samples were collected once in the acute stage, on the first day of admission. We used real-time RT-PCR to detect EV71 viremia. Demographical and clinical data were collected and the clinical severity was categorized into four grades. Data analysis was performed to identify the risk factors of viremia and the correlation between viremia and clinical severity of EV71 infection.
  
  
  RESULTS
  Of the total 224 enrolled patients, 59 (26%) patients were confirmed to have viremia. Two-thirds (68%) of viremic cases were detected within the first three days of infection. Viremia occurred more frequently in children under the age of one year old (odds ratios [OR] 4.82, p < 0.001) but the association between the presence of viremia and complicated EV71 infection was not found (OR 1.02, p = 0.96). In the viremia group, patients had significantly more severe complications if viremia was detected after the third day of disease onset (26% vs. 5%, p = 0.03).
  
  
  CONCLUSIONS
  Viremia occurred more frequently in children under the age of one year and viremia detected beyond three days after the onset of disease correlated with more severe disease in EV71 patients.
authors: Hao-Yuan
authors: HY
authors: Cheng
authors: Yi-Chuan
authors: YC
authors: Huang
authors: Ting-Yu
authors: TY
authors: Yen
authors: Shao-Hsuan
authors: SH
authors: Hsia
authors: Yu-Chia
authors: YC
authors: Hsieh
authors: Chung-Chen
authors: CC
authors: Li
authors: Department of Pediatrics, National Taiwan University Hospital and College of Medicine, National Taiwan University, Taipei, Taiwan. lychang@ntu.edu.tw.
authors: Luan-Yin
authors: LY
authors: Chang
authors: Li-Min
authors: LM
authors: Huang
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D029821:Enterovirus A, Human / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D004769:Enterovirus Infections / Q000150:complications* / Q000453:epidemiology / Q000821:virology; D058872:Epidemics; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction; D012307:Risk Factors; D012720:Severity of Illness Index; D013624:Taiwan / Q000453:epidemiology; D014766:Viremia / Q000453:epidemiology* / Q000209:etiology / Q000821:virology