title: Blood kinetics of Ebola virus in survivors and nonsurvivors.
abstract: BACKGROUND
  Infection with Ebola virus (EBOV) results in a life-threatening disease, with reported mortality rates between 50%-70%. The factors that determine patient survival are poorly understood; however, clinical observations indicate that EBOV viremia may be associated with fatal outcome. We conducted a study of the kinetics of Zaire EBOV viremia in patients with EBOV disease (EVD) who were managed at an Ebola Treatment Centre in Sierra Leone during the recent West African outbreak.
  
  
  METHODS
  Data from 84 EVD patients (38 survivors, 46 nonsurvivors) were analyzed, and EBOV viremia was quantified between 2 and 13 days after symptom onset. Time since symptom onset and clinical outcome were used as independent variables to compare EBOV viral kinetics in survivors and nonsurvivors.
  
  
  RESULTS
  In all patients, EBOV viremia kinetics was a quadratic function of time; however, EBOV viremia was 0.94 logarithm (log) copies per ml (cp/ml) (P = 0.011) higher in nonsurvivors than in survivors from day 2 after the onset of symptoms. Survivors reached peak viremia levels at an earlier time after symptom onset than nonsurvivors (day 5 versus day 7) and had lower mean peak viremia levels compared with nonsurvivors (7.46 log cp/ml; 95% CI, 7.17-7.76 vs. 8.60 log cp/ml; 95% CI, 8.27-8.93). Before reaching peak values, EBOV viremia similarly increased both in survivors and nonsurvivors; however, the decay of viremia after the peak was much stronger in survivors than in nonsurvivors.
  
  
  CONCLUSIONS
  Our results demonstrate that plasma concentrations of EBOV are markedly different between survivors and nonsurvivors at very early time points after symptom onset and may be predicative of outcome. Further studies focused on the early phase of the disease will be required to identify the causal and prognostic factors that determine patient outcome.
  
  
  BACKGROUND
  Italian Ministry of Health; Italian Ministry of Foreign Affairs; EMERGENCY's private donations; and Royal Engineers for DFID-UK.
authors.forename: Simone
authors.initials: S
authors.lastname: Lanini
authors.forename: Gina
authors.initials: G
authors.lastname: Portella
authors.forename: Francesco
authors.initials: F
authors.lastname: Vairo
authors.forename: Gary P
authors.initials: GP
authors.lastname: Kobinger
authors.forename: Antonio
authors.initials: A
authors.lastname: Pesenti
authors.forename: Martin
authors.initials: M
authors.lastname: Langer
authors.forename: Soccoh
authors.initials: S
authors.lastname: Kabia
authors.forename: Giorgio
authors.initials: G
authors.lastname: Brogiato
authors.forename: Jackson
authors.initials: J
authors.lastname: Amone
authors.forename: Concetta
authors.initials: C
authors.lastname: Castilletti
authors.forename: Rossella
authors.initials: R
authors.lastname: Miccio
authors.forename: Alimuddin
authors.initials: A
authors.lastname: Zumla
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Capobianchi
authors.forename: Antonino
authors.initials: A
authors.lastname: Di Caro
authors.forename: Gino
authors.initials: G
authors.lastname: Strada
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Ippolito
mesh_terms: D029043:Ebolavirus; D005260:Female; D005500:Follow-Up Studies; D019142:Hemorrhagic Fever, Ebola / Q000097:blood* / Q000175:diagnosis / Q000401:mortality*; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D017741:Survivors; D014766:Viremia / Q000175:diagnosis / Q000401:mortality*