title: A retrospective analysis of oral cholera vaccine use, disease severity and deaths during an outbreak in South Sudan.
abstract: OBJECTIVE
  To determine whether pre-emptive oral cholera vaccination reduces disease severity and mortality in people who develop cholera disease during an outbreak.
  
  
  METHODS
  The study involved a retrospective analysis of demographic and clinical data from 41 cholera treatment facilities in South Sudan on patients who developed cholera disease between 23 April and 20 July 2014 during a large outbreak, a few months after a pre-emptive oral vaccination campaign. Patients who developed severe dehydration were regarded as having a severe cholera infection. Vaccinated and unvaccinated patients were compared and multivariate logistic regression analysis was used to identify factors associated with developing severe disease or death.
  
  
  RESULTS
  In total, 4115 cholera patients were treated at the 41 facilities: 1946 (47.3%) had severe disease and 62 (1.5%) deaths occurred. Multivariate analysis showed that patients who received two doses of oral cholera vaccine were 4.5-fold less likely to develop severe disease than unvaccinated patients (adjusted odds ratio, aOR: 0.22; 95% confidence interval, CI: 0.11-0.44). Moreover, those with severe cholera were significantly more likely to die than those without (aOR: 4.76; 95% CI: 2.33-9.77).
  
  
  CONCLUSIONS
  Pre-emptive vaccination with two doses of oral cholera vaccine was associated with a significant reduction in the likelihood of developing severe cholera disease during an outbreak in South Sudan. Moreover, severe disease was the strongest predictor of death. Two doses of oral cholera vaccine should be used in emergencies to reduce the disease burden.
authors.affiliation: Ministry of Public Health, Centre Médical d'Arrondissement de Baré, Nkongsamba, Cameroon .
authors.forename: Cavin Epie
authors.initials: CE
authors.lastname: Bekolo
authors.affiliation: Centre for Research on the Epidemiology of Disasters, Institute of Health and Society, Université Catholique de Louvain, 30 Clos Chapelle-aux-Champs, Brussels, 1200, Belgium .
authors.forename: Joris Adriaan Frank
authors.initials: JA
authors.lastname: van Loenhout
authors.affiliation: Centre for Research on the Epidemiology of Disasters, Institute of Health and Society, Université Catholique de Louvain, 30 Clos Chapelle-aux-Champs, Brussels, 1200, Belgium .
authors.forename: Jose Manuel
authors.initials: JM
authors.lastname: Rodriguez-Llanes
authors.affiliation: Ministry of Health, Juba, South Sudan .
authors.forename: John
authors.initials: J
authors.lastname: Rumunu
authors.affiliation: Ministry of Health, Juba, South Sudan .
authors.forename: Otim Patrick
authors.initials: OP
authors.lastname: Ramadan
authors.affiliation: Centre for Research on the Epidemiology of Disasters, Institute of Health and Society, Université Catholique de Louvain, 30 Clos Chapelle-aux-Champs, Brussels, 1200, Belgium .
authors.forename: Debarati
authors.initials: D
authors.lastname: Guha-Sapir
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002771:Cholera / Q000401:mortality / Q000503:physiopathology* / Q000517:prevention & control*; D022121:Cholera Vaccines / Q000494:pharmacology*; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012720:Severity of Illness Index; D000068037:South Sudan / Q000453:epidemiology; D055815:Young Adult
chemical_list: D022121:Cholera Vaccines