The intrinsic vulnerability of networks to epidemics

Contact networks are convenient models to investigate epidemics, with nodes and links representing potential hosts and infection pathways, respectively. The outcomes of outbreak simulations on networks are driven both by the underlying epidemic model, and by the networks’ structural properties, so that the same pathogen can generate different epidemic dynamics on different networks. Here we ask whether there are general properties that make a contact network intrinsically vulnerable to epidemics (that is, regardless of specific epidemiological parameters). By conducting simulations on a large set of modelled networks, we show that, when a broad range of network topologies is taken into account, the effect of specific network properties on outbreak magnitude is stronger than that of fundamental pathogen features such as transmission rate, infection duration, and immunization ability. Then, by focusing on a large set of real world networks of the same type (potential contacts between field voles, Microtus agrestis), we showed how network structure can be used to accurately assess the relative, intrinsic vulnerability of networks towards a specific pathogen, even when those have limited topological variability. These results have profound implications for how we prevent disease outbreaks; in many real world situations, the topology of host contact networks can be described and used to infer intrinsic vulnerability. Such an approach can increase preparedness and inform preventive measures against emerging diseases for which limited epidemiological information is available, enabling the identification of priority targets before an epidemic event

Avances en teledetección para la prevención y detección temprana de Xylella fastidiosa en el marco de los proyectos H2020 POnTE y XF-ACTORS.

Informational article of the tasks carried out in WP6 of POnTE and WP3 of XF-ACTORS in a professional Spanish magazin

Effect of an early bitter taste experience on subsequent feather-pecking behaviour in laying hens

Recent studies showed that laying hens learn not to peck at bitter-tasting feathers from conspecifics. In the present experiment, feathers of newly hatched chicks were made distasteful by spraying them with a bitter-tasting substance (quinine). It was hypothesized that chicks could detect quinine and learn to avoid the downy feathers and the feathers of conspecifics later in life. Six groups of 10 high feather-pecking birds and six groups of 10 low feather-pecking birds were kept on litter. Half of each of these groups was quinine treated. Each bird in the quinine-treated groups was individually sprayed on a weekly basis for 25 weeks with a quinine solution. It was investigated whether the presence of quinine on the birds’ feather cover affected gentle and severe feather pecking. The result indicated that feathers made distasteful with quinine reduced severe feather pecking in young and adult birds as long as it was detected on birds feather cover

Displaying remotely sensed vegetation dynamics along natural gradients for ecological studies

Normalized difference vegetation index (NDVI) datasets are growing in popularity to represent vegetation dynamics in ecological studies. Because of its multidimensional nature, it is difficult to visualise the spatial and temporal components of NDVI datasets simultaneously. This letter presents a method to display vegetation dynamics as captured by the NDVI along natural gradients and to visualise and test correlations between vegetation phenology and animal movement