Video Experimental Relacionado
Updated: Jul 16, 2026
05:51
Intracerebroventricular and Intravascular Injection of Viral Particles and Fluorescent Microbeads into the Neonatal Brain
Published on: July 24, 2016
Efecto de la vacuna de vesículas de membrana externa contra la enfermedad meningocócica del grupo B en Noruega
G Bjune1, E A Høiby, J K Grønnesby
1National Institute of Public Health, Oslo, Norway.
Lancet (London, England)
|November 2, 1991
Resumen
Una vacuna meningocócica B de membrana externa mostró una eficacia del 57,2% en un gran ensayo noruego. Si bien es protectora, la vacuna también lo es.
Área de la Ciencia:
- Enfermedades infecciosas Enfermedades infecciosas.
- Vacunología Vacunología.
- Epidemiología La epidemiología.
Sus antecedentes:
- Noruega tiene la mayor incidencia de enfermedad meningocócica en el norte de Europa.
- Los meningococos del serogrupo B causan el 80% de los casos, con una alta tasa de mortalidad de aproximadamente el 10%.
Objetivo del estudio:
- Evaluar la eficacia de una vacuna de vesícula de membrana externa (VMO) contra la enfermedad meningocócica del serogrupo B.
- Para determinar si el nivel de protección de la vacuna justifica un programa público de vacunación.
Principales métodos:
- Un ensayo de eficacia a gran escala, aleatorizado, doble ciego y controlado con placebo en el que participaron 171.800 estudiantes de secundaria en Noruega.
- La escuela era la unidad de aleatorización.
- Informe urgente de sospecha de meningitis y/o casos de septicemia en estudiantes de entre 13 y 21 años.
Principales resultados:
- Se confirmaron 89 casos de enfermedad sistémica grave debido a meningococos del grupo B.
- Se produjeron 36 casos dentro del ensayo (11 escuelas vacunadas, 24 escuelas de placebo).
- La eficacia calculada de la vacuna fue del 57,2% (p = 0,012).
Conclusiones:
- La vacuna meningocócica B OMV confirió protección contra la enfermedad meningocócica del grupo B.
- La eficacia observada fue insuficiente para justificar un programa público de vacunación.
- Puede ser necesaria más investigación para mejorar la efectividad de la vacuna o explorar estrategias alternativas.
Más Videos Relacionados
Videos de Conceptos Relacionados
01:24Bacterial Meningitis
Bacterial meningitis is a severe infectious disease involving inflammation of the meninges, the protective membranes surrounding the brain and spinal cord. It occurs when pathogenic bacteria cross the blood–brain barrier and enter the cerebrospinal fluid. Common causative organisms include Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b, Listeria monocytogenes, and Escherichia coli K1. The exact route of entry varies by pathogen and host condition.Routes of Entry...
01:18Viral Meningitis
Viral meningitis is the most common form of meningitis and is often referred to as aseptic meningitis to indicate the absence of bacterial involvement. It is generally milder than bacterial meningitis, with symptoms including fever, headache, stiff neck, drowsiness, nausea, photophobia, and vomiting. Rarely, more severe manifestations or death may occur. Common causative agents include enteroviruses, particularly coxsackie A and B viruses and echoviruses, all members of the Enterovirus genus...
01:17Poliomyelitis
Poliomyelitis is caused by poliovirus, a small, non-enveloped, positive-sense RNA virus of the Picornaviridae family and Enterovirus genus. Transmission occurs primarily via the fecal-oral route, often through ingestion of contaminated water or food. The virus initially replicates in the oropharynx and intestinal mucosa, particularly in lymphoid tissues such as the tonsils, Peyer’s patches, and regional lymph nodes. Primary viremia follows, allowing dissemination throughout the body.In most...
01:27Cryptococcal Meningitis
Cryptococcal meningitis is a life-threatening opportunistic infection predominantly associated with HIV/AIDS, accounting for over 100,000 deaths annually worldwide. However, it also affects individuals with other forms of immunosuppression, including those undergoing immunosuppressive therapy, organ transplant recipients, patients with innate immunodeficiencies, and individuals with hematological disorders. The infection is caused mainly by Cryptococcus neoformans and Cryptococcus gattii,...
01:22Bacterial Meningitis I: Introduction
Bacterial meningitis is a severe, life-threatening inflammation of the meninges, particularly the pia mater and arachnoid mater, affecting the subarachnoid space, ventricles, and cerebrospinal fluid (CSF). If untreated, it can lead to significant neurological complications or death.Causative AgentsCommon pathogens vary with age and immune status. In adults, major organisms include Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae. Streptococcus agalactiae (group B...
01:26Bacterial Meningitis II: Pathophysiology
Bacterial meningitis typically begins when pathogens such as Neisseria meningitidis and Streptococcus pneumoniae colonize the nasopharynx and invade the bloodstream. This process is facilitated by bacterial virulence factors, such as polysaccharide capsules, which resist phagocytosis and complement-mediated killing. Less commonly, bacteria reach the central nervous system via contiguous spread from infections like otitis media or sinusitis, through congenital or acquired dural defects, or...