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Las infecciones neumocócicas son una causa importante de morbilidad, hospitalización y mortalidad, con dos grupos de edad de mayor incidencia y gravedad, uno pediátrico, los niños menores de 5 años (sobre todo los dos primeros años de edad), y otro de adulto (personas mayores de 65 años). La vacuna neumocócica conjugada heptavalente, comercializada en España en junio de 2001, es eficaz en niños menores de 2 años de edad e induce memoria inmunitaria, a diferencia de la vacuna no conjugada 23-va-lente. La cobertura de los serotipos de la vacuna heptava-lente en España es el 80 % de los que causan enfermedad neumocócica invasora y otitis media aguda en los niños de 2 a 59 meses de edad. La vacuna heptavalente es inmunó-gena, eficaz y segura. Su eficacia está demostrada en la prevención de la enfermedad invasora causada por los siete serotipos vacunales; también produce una disminución significativa de neumonía y una reducción de otitis media aguda; la vacuna tiene una indicación preferente: los niños menores de 2 años; los niños entre 2 y 5 años también se pueden beneficiar de la vacuna, pero con prioridad para los pertenecientes a grupos de riesgo. Un mejor co-nocimiento en nuestro medio de la epidemiología de la infección neumocócica y de la eficiencia de esta inmuniza-ción permitirá determinar la necesidad o no de incluir esta vacuna en el calendario de inmunizaciones sistemáticas.
Palabras clave:
Neumococo Infección neumocócica
Enfermedad neumocócica
Enfermedad invasora
Vacunación
Vacunas antineumocócicas
Vacuna conjugada neumocócica heptavalente
Pneumococcal disease is a major cause of morbidity, hospitalization and mortality. Two age groups show a greater incidence and severity of the disease: children under the age of 5 years (mainly during the first 2 years of life) and adults aged more than 65 years. The heptavalent pneumococcal conjugate vaccine, which was commercialized in Spain in June 2001, is efficacious in children aged less than 2 years and, unlike the non-conjugate 23-valent vaccine, it induces immunological memory. In Spain the heptavalent vaccine covers 80 % of serotypes causing pneumococcal invasive disease and acute otitis media in children aged 2-59 months. The heptavalent vaccine has been shown to be immunogenic, efficacious and safe. It has proven efficacy in the prevention of invasive disease caused by the seven vaccine serotypes. In addition, it significantly decreases pneumonia and also prevent acute otitis media. The vaccine is preferably indicated in children aged less than 2 years; children aged 2-5 years may also benefit from the vaccine but those in risk groups should be prioritized. Greater knowledge of the epidemiology of pneumococcal disease and the efficiency of this vaccine in Spain will determine whether it should be included in the immunization schedule.
Key words:
Pneumococcus
Pneumococcal infection
Pneumococcal disease
Invasive disease
Vaccination Pneumococcal vaccines
Pneumococcal 7-valent conjugate vaccine
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