title: Post-infectious fatigue syndrome in dengue infection.
abstract: BACKGROUND
  Although the acute manifestations of dengue are well known, few studies have assessed the long-term consequences of dengue infection. We prospectively studied the incidence and factors associated with fatigue in a cohort of patients following dengue infection.
  
  
  METHODS
  We included patients with serologically confirmed dengue infection admitted to the National University Hospital, Singapore, during a dengue outbreak from October-November 2005. The severity of dengue was graded as dengue fever, dengue haemorrhagic fever and dengue shock syndrome. A follow-up telephone interview was performed two months following hospital discharge, where a Fatigue Questionnaire was administered. The presence of significant fatigue was considered as the main outcome measure. Significance was assessed at P<0.05.
  
  
  RESULTS
  One hundred twenty-seven patients, 71 (55.9%) males and 56 (44.1%) females, of mean age 36.06 years (range, 16-70; S.D., 13.722), participated in this study. Twenty-five (19.7%) patients had dengue haemorrhagic fever and the remaining 102 (80.3%) had dengue fever. In multivariate analysis, increased age, female sex, the presence of chills, and the absence of rashes were significantly associated with the development of fatigue post-dengue infection. There was no significant association between fatigue and dengue severity.
  
  
  CONCLUSIONS
  This observation represents the first systematic evidence that dengue can result in clinical disease beyond the acute phases of infection. Host factors, such as age and sex may be important in the pathogenesis of this clinical entity.
authors.affiliation: Department of Medicine, Yong Loo Lin School of Medicine, National University Singapore, Singapore. raymond_seet@nus.edu.sg
authors.forename: Raymond C S
authors.initials: RC
authors.lastname: Seet
authors.forename: Amy M L
authors.initials: AM
authors.lastname: Quek
authors.forename: Erle C H
authors.initials: EC
authors.lastname: Lim
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D003715:Dengue / Q000150:complications*; D015673:Fatigue Syndrome, Chronic / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D006801:Humans; D015994:Incidence; D007407:Interviews as Topic; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012307:Risk Factors; D012737:Sex Factors; D012846:Singapore / Q000453:epidemiology