Tos ferina, un problema vigente de salud pública en México: Planteamiento de la necesidad para introducir una nueva vacuna / Shaping a new strategy against B. pertussis: a public health problem in Mexico

A pesar de la vacunación contra B. pertussis, se sigue reportando un gran número de muertes por tos ferina a nivel mundial. La pérdida de la inmunidad a través de los años y el incremento de la incidencia en adolescentes y adultos han sustentado el papel de estos grupos de edad en la transmisión de la enfermedad. Diversos países han implementado nuevas estrategias de vacunación con la finalidad de reducir su transmisión y significado clínico. En México, la tos ferina es un problema de salud pública vigente, y su control presenta algunos obstáculos, como la sospecha clínica fuera de la etapa del lactante, la confirmación del diagnóstico, los esquemas de vacunación tardíos o incompletos y la dificultad para limitar su transmisibilidad. La introducción de nuevas estrategias de vacunación en adolescentes y adultos, así como en las mujeres embarazadas, contribuirían al control de la enfermedad y limitarían sus complicaciones.

Despite vaccination against pertussis, there are still a large number of pertussis deaths worldwide. Waning vaccine-induced immunity and the gradual increase in reported incidence among adolescents and adults have supported the role of these age groups in the transmission. Several countries have implemented a booster vaccination in order to reduce transmission and clinical significance. Pertussis is a current public health problem in Mexico. The clinical suspicion in toddlers, adolescents and adults, delayed or incomplete vaccination series and diagnosis confirmation are the most important challenges for pertussis control. The introduction of new vaccination strategies in adults and adolescents as well as pregnant women should improve disease control.

[Booster vaccination against Bordella pertussis during pregnancy]. / Vacunación de refuerzo contra Bordetella pertussis en mujeres embarazadas.

During the last decades, the incidence of whopping cough, has been rising worldwide, despite the high coverage of the immunization programs. The highest mortality is found among children under 6 month of age, who are too young to have completed a primary vaccination series with three doses the pertussis vaccine, nevertheless this disease also affects adolescents and adults, who may only manifest mild symptomatology. Hence they do not get diagnosed or treated, becoming a potential community source of infection for young children. In order to prevent this transmission, the recommendation of vaccinating adolescents and adults, including of women in child bearing age, was issued. Nevertheless the immunization coverage among these populations was low. Postpartum vaccination was also recommended, but recent evidence have shown that the antibody levels in breast milk are detectable at least a week after immunization, allowing a window of opportunity for the infection in the newborn. Finally, it has been suggested that a booster dose against Bordetella pertussis, given to pregnant women is safe and immunogenic. Therefore, the antibody transferred across the placenta and through breast milk, could protect the product in the early stages of life.

[Consensus on the clinical and microbiologic diagnosis of Bordetella pertussis, and infection prevention. Expert Group on Pertussis Vaccination]. / Consenso para el diagnóstico clínico y microbiológico y la prevención de la infección por Bordetella pertussis. Grupo de expertos en vacunación contra tos ferina.

Pertussis continues to be responsible for a significant disease burden worldwide. Although immunization practices have reduced the occurrence of the disease among children, waning vaccine- and infection-induced immunity still allows the disease to affect adolescents and adults who, in turn, can transmit the disease to non-immunized or partially immunized infants. This document is the result of a meeting in Mexico City of international experts who analyzed recent medical information in order to establish the current status of the epidemiology, diagnosis and surveillance of pertussis and, especially, the value of the dTpa booster dose in adolescents and adults as a pertussis prevention strategy in Mexico.

Consenso para el diagnóstico clínico y microbiológico y la prevención de la infección por Bordetella pertussis / Consensus on the clinical and microbiologic diagnosis of Bordetella pertussis, and infection prevention

La tos ferina sigue siendo responsable de una carga de enfermedad importante en el mundo. Aunque la implementación del uso de la vacuna contra esta enfermedad ha disminuido en gran medida el número de casos en la población pediátrica, se ha observado que la inmunidad inducida por la vacuna y por la infeccion natural disminuye con el tiempo lo que hace nuevamente susceptibles a adolescentes y adultos jóvenes que pueden transmitir la enfermedad a lactantes no inmunizados o con esquema de vacunación incompleto. Este documento, resultado de la reunión de un grupo internacional de expertos en la Ciudad de México, ha analizado la información médica reciente para establecer el estado actual de la epidemiología, diagnóstico, vigilancia y, especialmente, el valor de la dosis de refuerzo con dTpa en adolescentes y adultos como estrategia de prevención de tos ferina en México.

Pertussis continues to be responsible for a significant disease burden worldwide. Although immunization practices have reduced the occurrence of the disease among children, waning vaccine- and infection-induced immunity still allows the disease to affect adolescents and adults who, in turn, can transmit the disease to non-immunized or partially immunized infants. This document is the result of a meeting in Mexico City of international experts who analyzed recent medical information in order to establish the current status of the epidemiology, diagnosis and surveillance of pertussis and, especially, the value of the dTpa booster dose in adolescents and adults as a pertussis prevention strategy in Mexico.

Effect of rotavirus vaccination on death from childhood diarrhea in Mexico.

BACKGROUND: A phased introduction of a monovalent rotavirus vaccine occurred in Mexico from February 2006 through May 2007. We assessed the effect of vaccination on deaths from diarrhea in Mexican children in 2008 and 2009. METHODS: We obtained data on deaths from diarrhea, regardless of cause, from January 2003 through May 2009 in Mexican children under 5 years of age. We compared diarrhea-related mortality in 2008 and during the 2008 and 2009 rotavirus seasons with the mortality at baseline (2003-2006), before the introduction of the rotavirus vaccine. Vaccine coverage was estimated from administrative data. RESULTS: By December 2007, an estimated 74% of children who were 11 months of age or younger had received one dose of rotavirus vaccine. In 2008, there were 1118 diarrhea-related deaths among children younger than 5 years of age, a reduction of 675 from the annual median of 1793 deaths during the 2003-2006 period. Diarrhea-related mortality fell from an annual median of 18.1 deaths per 100,000 children at baseline to 11.8 per 100,000 children in 2008 (rate reduction, 35%; 95% confidence interval [CI], 29 to 39; P<0.001). Among infants who were 11 months of age or younger, diarrhea-related mortality fell from 61.5 deaths per 100,000 children at baseline to 36.0 per 100,000 children in 2008 (rate reduction, 41%; 95% CI, 36 to 47; P<0.001). As compared with baseline, diarrhea-related mortality was 29% lower for children between the ages of 12 and 23 months, few of whom were age-eligible for vaccination. Mortality among unvaccinated children between the ages of 24 and 59 months was not significantly reduced. The reduction in the number of diarrhea-related deaths persisted through two full rotavirus seasons (2008 and 2009). CONCLUSIONS: After the introduction of a rotavirus vaccine, a significant decline in diarrhea-related deaths among Mexican children was observed, suggesting a potential benefit from rotavirus vaccination.

Agentes etiológicos causantes de infecciones nosocomiales relacionadas con catéteres intravasculares / Agents associated to intravascular catheter-related nosocomial infections

Introducción. Objetivo: establecer la frecuencia bacteriana y factores de riesgo relacionados con las infecciones nosocomiales en pacientes que se les insertó catéteres intravasculares, basados en criterios clínicos y microbiológicos. Material y métodos. Se realizó un estudio clínico, prospectivo, abierto, descriptivo y longitudinal, de junio de 1996 a octubre de 1998, en 50 pacientes de ambos sexos, cuya edad osciló de 1 día de vida a 14.5 años, a quienes se les colocaron 100 catéteres insertados por venodisección. Se tomaron 2 mL de sangre por la luz y de una vena periférica ajena, al momento de su instalación, a las 24 y a las 72 horas, y posteriormente cada 7 días hasta retirarlos y se incubaron a 37ºC, el extremo del catéter se procesó en agar sangre. En los casos en que la infección se relacionó con el sitio de entrada o con el túnel se llevó a cabo una tinción de Gram y cultivo cuantitativo de la secreción. Resultados. Se eliminaron 30 de los 100 catéteres, de los 70 restantes, la tasa de asociación días/infección/catéter fue de 2.9 infecciones con la siguiente distribución; de 1.2 del sitio de entrada, 1.2 sistémicas y 0.5 del túnel. Se identificó Staphylococcus aureus y Staphyloccoccus epidermis (57.6 por ciento) y Pseudomonas aeruginosa (11.5 por ciento). Conclusiones. La tasa de incidencia de infecciones relacionadas con el catéter venoso central en el estudio fue menor a la reportada en la literatura mundial, con características bacteriológicas y de localización semejantes