Back to search


EMIDA ERA-Net Vector-borne Infections: risk based and cost effective surveillance systems

Awarded: NOK 3.0 mill.

Project Manager:

Project Number:


Application Type:

Project Period:

2012 - 2016

Funding received from:


The overall objective of the project is to develop a functional framework for dynamic risk-based surveillance of vector-borne diseases. This has been achieved by combining (1) the risk of introduction of infection, (2) potential for transmission if the infection is introduced and (3) syndromic surveillance in a so-called Joint Risk Score. The input data are parameters that already have been collected for other purposes (weather data, environmental data, import data and data on syndromes) so that costs can be kept low. The Joint Risk Score gives a combined measure for the risk of a potential outbreak of vector-borne infections and subsequent spread in animal populations. Thereby, the surveillance can be targeted in time and in areas with elevated risk and the surveillance activities can be adapted to available resources nationally and within the EU. The Norwegian Veterinary Institute has made available Norwegian trap data of Culicoides (midges) which are vectors of bluetongue and African horse sickness. The data have been analysed together with data from several European countries by other partners in the project and maps and in the occurrence of midges in time and space in Europe have been modelled using weather data (temperature) and vegetation types (satellite data) as input. The Norwegian Veterinary Institute has primarily focused on syndromic surveillance of bluetongue and West Nile virus. In this context, syndromes are events that may occur due to disease and by syndromic surveillance one aim to identify areas and time periods with an unusually high incidence of such events. For bluetongue, we have made a system for syndromic surveillance based on data on mortality and abortions gathered from the Norwegian Dairy Herd Recording (Tine dairies). These are analysed for variation in time and space to identify areas and times where the occurrence of events indicate a higher risk for an on-going outbreak of bluetongue. To assess the system's ability to detect bluetongue outbreaks, we have made a spread model for simulating increase in mortality and abortions during a bluetongue outbreak under Norwegian conditions. Preliminary results indicate that surveillance on these syndromes has a low sensitivity for early detection of a bluetongue outbreak. The work is on-going. Similarly, the project has access to the data of trotter horses with no-start from The Norwegian Trotting Company for use in syndromic surveillance of West Nile virus. Analysis of variation in no-starts that in theory can be related to disease due to West Nile virus has begun. The Norwegian Veterinary Institute has contributed Norwegian data to an evaluation of all partner countries' bluetongue surveillance. The evaluation shows that the sensitivity of the Norwegian surveillance programme for bluetongue is sufficient to document freedom for disease and that the surveillance is cost-effective.

The proposed surveillance system will be based on computer models scanning and interpreting risk parameters already collected for other purposes (weather data, environmental data, import data, syndromes) and costs may therefore be very low. Only during ti me periods and in areas of elevated risk will costly active surveillance activities gradually be suggested based on cost-effectiveness estimates and the desired sensitivity. This framework for continuous risk based surveillance will be based on three ind ependent pillars: (1) risk of introduction, (2) potential for spread if introduced and (3) syndrome surveillance. The sensitivity of the system will be evaluated with scenario trees. The surveillance system will be built on present knowledge of disease bi ology and vector ecology. The surveillance system will be modular allowing for easy and continuous updating of the underlying models whenever new or more precise information becomes available. Using selected VBD we will demonstrate how risk and hence the need for active surveillance can be communicated as dynamic maps of risk displayed on the internet at a weekly resolution. We will also demonstrate the surveillance system on historic data for a 30-year period to determine the average risk and hence cost of surveillance. This will assist decision makers at national and EU level to estimate long-term expenses for surveillance in various regions. Furthermore we will make spatially specific 50-year prognoses based on existing climate change predictions.

Publications from Cristin

No publications found

No publications found

No publications found

No publications found

Funding scheme: