RESUMEN
The first week of September 2013, the National Epidemiological Surveillance System identified two cases of cholera in Mexico City. The cultures of both samples were confirmed as Vibrio cholerae serogroup O1, serotype Ogawa, biotype El Tor. Initial analyses by PFGE and by PCR-amplification of the virulence genes, suggested that both strains were similar, but different from those previously reported in Mexico. The following week, four more cases were identified in a community in the state of Hidalgo, located 121 km northeast of Mexico City. Thereafter a cholera outbreak started in the region of La Huasteca. Genomic analyses of the four strains obtained in this study confirmed the presence of Pathogenicity Islands VPI-1 and -2, VSP-1 and -2, and of the integrative element SXT. The genomic structure of the 4 isolates was similar to that of V. cholerae strain 2010 EL-1786, identified during the epidemic in Haiti in 2010.
Asunto(s)
Técnicas de Tipificación Bacteriana , Cólera/microbiología , ADN Bacteriano/química , Genoma Bacteriano , Análisis de Secuencia de ADN , Vibrio cholerae O1/clasificación , Vibrio cholerae O1/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Cólera/epidemiología , ADN Bacteriano/genética , Brotes de Enfermedades , Femenino , Orden Génico , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Sintenía , Vibrio cholerae O1/genética , Vibrio cholerae O1/fisiología , Adulto JovenRESUMEN
On September 2 and 6, 2013, Mexico's National System of Epidemiological Surveillance identified two cases of cholera in Mexico City. Rectal swab cultures from both patients were confirmed as toxigenic Vibrio cholerae serogroup O1, serotype Ogawa, biotype El Tor. Pulsed-field gel electrophoresis and virulence gene amplification (ctxA, ctxB, zot, and ace) demonstrated that the strains were identical to one another but different from strains circulating in Mexico previously. The strains were indistinguishable from the strain that has caused outbreaks in Haiti, the Dominican Republic, and Cuba. The strain was susceptible to doxycycline, had intermediate susceptibility to ampicillin and chloramphenicol, was less than fully susceptible to ciprofloxacin, and was resistant to furazolidone and trimethoprim-sulfamethoxazole. An investigation failed to identify a common source of infection, additional cases, or any epidemiologic link between the cases. Both patients were treated with a single, 300-mg dose of doxycycline, and their symptoms resolved.