title: Use of a cholera rapid diagnostic test during a mass vaccination campaign in response to an epidemic in Guinea, 2012.
abstract: BACKGROUND
  During the 2012 cholera outbreak in the Republic of Guinea, the Ministry of Health, supported by Médecins Sans Frontières - Operational Center Geneva, used the oral cholera vaccine Shanchol as a part of the emergency response. The rapid diagnostic test (RDT) Crystal VC, widely used during outbreaks, detects lipopolysaccharide antigens of Vibrio cholerae O1 and O139, both included in Shanchol. In the context of reactive use of a whole-cell cholera vaccine in a region where cholera cases have been reported, it is essential to know what proportion of vaccinated individuals would be reactive to the RDT and for how long after vaccination.
  
  
  RESULTS
  A total of 108 vaccinated individuals, selected systematically among all persons older than one year, were included at vaccination sites and 106 were included in the analysis. Stools samples of this cohort of vaccinated participants were collected and tested with the RDT every day until the test was negative for two consecutive visits or for a maximum of 7 days. A total of 94.3% of cholera vaccine recipients had a positive test after vaccination; all except one of these positive results were reactive only with the O139 antigen. The mean time to become negative in those with an initial positive result after vaccination was 3.8 days, standard deviation 1.1 days.
  
  
  CONCLUSIONS
  The RDT Crystal VC becomes positive in persons recently vaccinated against cholera, although almost exclusively to the O139 antigen. This reactivity largely disappeared within five days after vaccination. These results suggest that the test can be used normally as soon as 24 hours after vaccination in a context of O1 epidemics, which represent the vast majority of cases, and after a period of five days in areas where V. cholerae O139 is present. The reason why only O139 test line became positive remains to be investigated.
authors: European Programme for Intervention Epidemiology Training, European Centre for Disease Prevention and Control, Stockholm, Sweden. imartinezpino@gmail.com
authors: Isabel
authors: I
authors: Martinez-Pino
authors: Francisco J
authors: FJ
authors: Luquero
authors: Kéïta
authors: K
authors: Sakoba
authors: Souleymane
authors: S
authors: Sylla
authors: Melatwork
authors: M
authors: Haile
authors: Rebecca F
authors: RF
authors: Grais
authors: Iza
authors: I
authors: Ciglenecki
authors: Marie-Laure
authors: ML
authors: Quilici
authors: Anne-Laure
authors: AL
authors: Page
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002771:Cholera / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D022121:Cholera Vaccines / Q000008:administration & dosage*; D003955:Diagnostic Tests, Routine / Q000379:methods*; D058872:Epidemics; D005243:Feces / Q000382:microbiology; D005260:Female; D016701:Guinea / Q000453:epidemiology; D006801:Humans; D008297:Male; D032541:Mass Vaccination; D008875:Middle Aged; D013997:Time Factors; D041241:Vibrio cholerae O1 / Q000302:isolation & purification*; D041242:Vibrio cholerae O139 / Q000302:isolation & purification*; D055815:Young Adult
chemical_list: D022121:Cholera Vaccines
references: Microbiology (Reading). 1999 Sep;145 ( Pt 9):2477-2484
references: 10517600
references: Clin Diagn Lab Immunol. 2003 May;10(3):476-8
references: 12738652
references: Indian J Med Res. 2012 Apr;135(4):523-8
references: 22664501
references: Trop Med Int Health. 2009 Sep;14(9):1117-21
references: 19624473
references: PLoS One. 2012;7(5):e36930
references: 22662131
references: Infect Immun. 2001 May;69(5):3488-93
references: 11292781
references: BMC Infect Dis. 2006 Feb 01;6:17
references: 16451731
references: PLoS Negl Trop Dis. 2013 Oct 17;7(10):e2465
references: 24147164
references: Lancet Infect Dis. 2007 Aug;7(8):521-30
references: 17584531
references: PLoS Negl Trop Dis. 2012;6(10):e1845
references: 23071851
references: Lancet. 2009 Nov 14;374(9702):1694-702
references: 19819004
references: PLoS One. 2012;7(5):e37360
references: 22666350
references: Jpn J Infect Dis. 2010 Jul;63(4):234-8
references: 20657061
references: Proteins. 2008 Jan 1;70(1):284-8
references: 17876834
references: Wkly Epidemiol Rec. 2009 Dec 11;84(50):517-32
references: 19999831
references: Trop Med Int Health. 2006 Jan;11(1):49-55
references: 16398755