Vacunar a los niños podría resultar efectivo para tratar de controlar la propagación de la influenza
De acuerdo a una investigación de la Universidad de Warwick, en el Reino Unido, dirigir las disponibilidades limitadas de la vacuna contra la influencia a su uso en niños, podría resultar efectivo. El estudio sugiere que, con vistas a apoyar otras medidas de control, esta estrategia podría ayudar a impedir la diseminación de las pandemias tales como la actual de influenza porcina.
A partir de la declaración de la Organización Mundial de la Salud de una pandemia global de influenza porcina H1N1, los países se afanan por hallar medidas para impedir su diseminación. Ellas incluyen el uso de tratamiento antiviral, distanciamiento social (por ejemplo, el cierre de escuelas y el paro del transporte público), y la cuarentena de individuos infectados.
Las compañías farmacéuticas también han intensificado la producción de vacunas efectivas contra esta cepa particular del virus. Sin embargo, si la propagación de la enfermedad se incrementa significativamente en el otoño como predicen algunos científicos, es poco probable que la disponibilidad de las vacunas sea suficiente para vacunar poblaciones enteras. http://www2.warwick.ac.uk/newsandevents/pressreleases/vaccinating_children_may
In research published in the journal Epidemiology and Infection, Dr Thomas House and Professor Matt Keeling from the University of Warwick’s Department of Biological Sciences have used computer modeling to predict the spread of pandemic influenza and to look at ways of controlling it effectively, particularly where supplies of vaccine are not sufficient for universal coverage.
The researchers showed that, as might be expected, the disease is likely to spread fastest in densely-populated conurbations, suggesting that these should be priority areas for tackling the spread. However, they showed that vaccinating entire households at random was an inefficient use of resources; instead, vaccinating key individuals offered sufficient protection to others in their household.
Although a simplification of the complex reality of pandemic flu transmission, the researchers believe their model provides a robust argument for vaccinating children.
“Our models suggest that the larger the household – which in most cases means the more children living at home – the more likely the infection is to spread,” says Professor Keeling. “This doesn’t mean that everyone in the household needs to be vaccinated, but suggests that vaccination programmes for children might help control a potential pandemic.”
The researchers argue that targeting children for vaccination would not only help protect those at greatest risk of exposure to the virus, but would also offer protection to unvaccinated adults. This so-called “herd immunity” effect would mean that significantly less vaccine would be necessary to help control the spread of the virus than if it were offered to everyone.
“Given that children are generally at particular risk from the disease, we believe that vaccination programmes for the young can be justified,” says Dr House. “Although not sufficient to prevent a pandemic in themselves, such steps may support other control measures such as social distancing, antiviral drugs or quarantine.”
The current study focuses on household transmissions. In the event of a disease outbreak, other modes of transmission are also likely, such as at work or on public transport. However, data for these modes is harder to come by. Professor Keeling and Dr House, together with colleagues at the University of Liverpool, are currently running www.contactsurvey.org, a survey on contact patterns which they hope will help to quantify the relative importance of each context.
“We think it is unlikely that including these other contexts in our model will change the conclusion regarding vaccinating children,” says Dr House. “In every city studied, households are seen to play a key role in the transmission of close-contact diseases like influenza.”
Publicado: jun 18th, 2009.