Diphtheria in the Dominican Republic: reduction of cases following a large outbreak.

OBJECTIVE: To describe the most recent outbreak of diphtheria in the Dominican Republic and the disease's occurrence and vaccination coverage in 2004-2013. METHODS: Clinical data of diphtheria cases that occurred in 2004 and that met the study's case definition were reviewed along with socioeconomic and epidemiological information from the cases' families. Univariate and multivariate analyses were performed to assess risk factors for fatal diphtheria. Routine surveillance and vaccination coverage data are presented. RESULTS: From January 2004-April 2005, a total of 145 diphtheria cases were reported; 80 (66%) of the 122 cases reported in 2004 met the case definition; 26 were fatal (case-fatality rate: 32.5%). Incidence was highest in the group 1-4 years of age at 5.3 per 100 000; 62.5% were male. Of the 80 cases, 61 (76%) where hospitalized in Hospital A, 17 in Hospital B, and 2 in two other hospitals. Earlier onset (first half of 2004), birth order, and tracheotomy were associated with fatal diphtheria (P < 0.05); cases in Hospital A were also more likely to be fatal (P = 0.066). The average annual diphtheria incidence was 4.91 cases/1 million people in 2000-2003, climbed to 8.8 cases per million in 2004-2005, and dropped to 0.38 in 2006-2014; no diphtheria cases have been reported since 2011. DTP3 vaccination coverage ranged from 72%-81% in 2000-2004 and from 81%-89% in 2005-2013. CONCLUSIONS: The 2004-2005 diphtheria outbreak in the Dominican Republic resulted in important and avoidable morbidity and mortality. Annual cases declined and no cases have been reported in recent years. Maintaining high vaccination coverage and diligent surveillance are crucial to preventing diphtheria outbreaks and controlling the disease.

Diphtheria in the Dominican Republic: reduction of cases following a large outbreak / Difteria en la República Dominicana: reducción de casos tras un extenso brote epidémico

OBJECTIVE: To describe the most recent outbreak of diphtheria in the Dominican Republic and the disease's occurrence and vaccination coverage in 2004-2013. METHODS: Clinical data of diphtheria cases that occurred in 2004 and that met the study's case definition were reviewed along with socioeconomic and epidemiological information from the cases' families. Univariate and multivariate analyses were performed to assess risk factors for fatal diphtheria. Routine surveillance and vaccination coverage data are presented. RESULTS: From January 2004-April 2005, a total of 145 diphtheria cases were reported; 80 (66%) of the 122 cases reported in 2004 met the case definition; 26 were fatal (case-fatality rate: 32.5%). Incidence was highest in the group 1-4 years of age at 5.3 per 100 000; 62.5% were male. Of the 80 cases, 61 (76%) where hospitalized in Hospital A, 17 in Hospital B, and 2 in two other hospitals. Earlier onset (first half of 2004), birth order, and tracheotomy were associated with fatal diphtheria (P < 0.05); cases in Hospital A were also more likely to be fatal (P = 0.066). The average annual diphtheria incidence was 4.91 cases/1 million people in 2000-2003, climbed to 8.8 cases per million in 2004-2005, and dropped to 0.38 in 2006-2014; no diphtheria cases have been reported since 2011. DTP3 vaccination coverage ranged from 72%-81% in 2000-2004 and from 81%-89% in 2005-2013. CONCLUSIONS: The 2004-2005 diphtheria outbreak in the Dominican Republic resulted in important and avoidable morbidity and mortality. Annual cases declined and no cases have been reported in recent years. Maintaining high vaccination coverage and diligent surveillance are crucial to preventing diphtheria outbreaks and controlling the disease.

OBJETIVO: Describir el brote epidémico más reciente de difteria en la República Dominicana, la incidencia de la enfermedad y la cobertura de la vacunación del 2004 al 2013. MÉTODOS: Se analizaron los datos clínicos de los casos de difteria acaecidos en el 2004 y que cumplieron con la definición de caso del estudio, junto con la información socioeconómica y epidemiológica de las familias en las que aparecieron los casos. Se llevaron a cabo análisis de una sola variable y de múltiples variables para evaluar los factores de riesgo de difteria mortal. Se presentan los datos de vigilancia ordinaria y cobertura vacunal. RESULTADOS: De enero del 2004 a abril del 2005, se notificaron un total de 145 casos de difteria; 80 (66%) de los 122 casos notificados en el 2004 cumplieron con la definición de caso; 26 fueron mortales (tasa de letalidad por caso: 32,5%). La incidencia más alta (5,3 por 100 000) se produjo en el grupo de 1 a 4 años de edad; 62,5% fueron varones. De los 80 casos, 61 (76%) se hospitalizaron en el Hospital A, 17 en el Hospital B, y 2 en otros dos hospitales. La aparición más temprana (primera mitad del 2004), el orden de nacimiento y la traqueotomía se asociaron con difteria mortal (P < 0 ,05); la probabilidad de evolución mortal fue mayor en los casos ingresados en el Hospital A (P = 0,066). La incidencia promedio anual de difteria fue de 4,91 casos por millón de personas del 2000 al 2003, ascendió a 8,8 casos por millón durante los años 2004 y 2005, y descendió a 0,38 del 2006 al 2014; no se han notificado casos de difteria desde el 2011. La cobertura de la vacunación con DTP3 varió de 72 a 81% del 2000 al 2004 y de 81 a 89% del 2005 al 2013. CONCLUSIONES: El brote epidémico de difteria de los años 2004 y 2005 en la República Dominicana ocasionó una importante morbimortalidad prevenible. Se produjo un descenso en la incidencia de casos y no se han notificado nuevos casos en los últimos años. El mantenimiento de una alta cobertura vacunal y de una vigilancia eficiente es crucial para la prevención de los brotes epidémicos de difteria y el control de la enfermedad.