Evaluating and controlling
EUR 2 984 712 Duration
2. Technical and policy support
of the EUBTNet system and obtain from EUBTNet the surveillance data required by the WP1 with the following justifications:
•
data in the EUBTNet system belong to the national competent authorities (i.e.the involved ministries of the Member States);
•
it would not have been difficult for the institutions involved in the project to be granted the permission to use aggre- gated data for the aims and scopes of the project;•
data in the EUBTNet system is the offi- cial information available from the Member States, therefore the use of EUBTNet data guarantees the con- sistency with the official situation of member countries;•
since the Medreonet project requires only aggregate data on the basis of administrative units, the proper man- agement of sensible data can be easily assured.WP2: Regional surveillance of vectors
The general objectives of this WP2 consisted in the strengthening of Culicoides entomo- logical surveillance in Europe and neighbour- ing countries. The specific objectives are the evaluation and the harmonisation of:
(i) surveillance protocols; and
(ii) available tools for trapping, identifica- tion of vectors and modelling of vector habitat.
The various deliverables that have been achieved could all be considered as potential applications, particularly:
•
the recommendation of the optimal trap design for sampling Culicoides;•
the development of a guide for the identification of Culicoides vectors and potential vectors;•
the recommendation of optimal surveillance protocols for Culicoides;•
the development of standardised proto- cols for detection and estimation of abundance of Culicoides;•
the development of a reference collec- tion of C. imicola specimens for DNA analysis.WP3: Molecular epidemiology
The general objectives of this WP3 con- sisted in the distribution, origins and move- ment of the different BTV and EHDV strains, by characterisation of well documented iso- lates of different serotypes.
•
Expanding the existing sequence data- bases for genome segments 2, 6 and others of BTV and related orbiviruses, including high quality data for repre- sentative and well documented isolates of different virus serotypes from differ- ent geographical locations is one of the application of this project and is very use- ful in terms of awareness when new out- breaks occur in orbiviruses free countries.•
The characterisation of novel and exist- ing BTV/EHDV strains from Europe and the Mediterranean basin is helping in the determination of their geographical distribution, movement, potential for reassortment and their original sources (topotypes).•
The identification of diagnostic tools such as molecular probes and pri mers for the rapid/early identification of new strains- serotypes is also one of the major appli- cations for all of the participants.WP4: Database, web design and GIS
The general objective of this WP4 was to develop a Culicoides-borne virus network through a website which will provide a plat- form of Internet-based tools to be used by partners and other interested parties, to enable:
(i) effective information exchange between partners on technical and adminis- trative CA-related bluetongue AHS and EHD activities (restricted-access website);
(ii) information related to the CA to be imparted to the wider scientific com- munity and to other stakeholders with an interest in the control of bluetongue and AHS (open-access website);
(iii) a forum for discussions on the vertical work packages:
•
to develop a web-enabled geographic information system (GIS) to present epidemiological data and to allow a rapid spread of information related to the diseases;•
to provide a real-time interactive mapping system of the main epide- miological aspects to facilitate the decision-making process and man- agement of control activities at cen- tral and local level.The online procedure is an application developed through an ASP page providing a form that participants can fill in when needed. The online updating system has been implemented in all the web-GIS ser- vices developed: BT outbreaks, BT entomo- logical surveillance, AHS outbreaks, EHD outbreaks.
Through a username and password, users can be identified and authorised and they can insert all the information related to their own country. At the moment, data on presence/absence of the disease can be added, but any additional information required by the participants can be eas- ily added in the form and the database including disease distribution, viral and serological activity, entomological activity, control measures.
WP5: Risk assessment
The general objective of this WP5 was to standardise methods for the geograph- ical assessment of the risk of BT/AHS/EHD spread in the Mediterranean basin and Europe.
In order to obtain a concept for geographi- cal risk assessment of BT/AHS/EHD, several
analyses were performed and aimed at the following potential applications.
•
Transmission pathways from currently affected areas have been developed using international standards for risk assessments. The pathways cover both vector-related transmission as well as spread related to trade.•
A review has been conducted with respect to published models that can be used for the assessment of infection probabilities of specified regions with a methodological guideline to be used in order to classify specific regions or Member States with respect to BT risk.•
Validation of the risk assessment using case studies in selected countries (Alge- ria, Bulgaria, Tunisia and Turkey) with the collection of samples to identify exotic strains of BT/AHS/EHD and trapping graphically presented as maps.•
Based on the epidemiology of BT/AHS/EHD, risk-based surveillance approaches have been developed. Risk-based sur- veillance is defined as a surveillance programme that includes risk factors for increased probability of infection in specified populations and/or regions as well as the outcome of risk assessments conducted. Thus, the results of the risk assessments will be used as input for the planning of surveillance. It is antici- pated that sampling intensity, target population and sampling interval in sur- veillance programmes are dependent on the risk category of the Member State or region. Different risk analysis mod- els have been built, to determine the risk of overwintering and introduction of bluetongue virus. The results of the models determine the factors that have more importance in the maintenance/
introduction of the virus and, as a con- sequence, the sub-populations where surveillance can be more sensitive in detecting the infection: quantitative assessment of the probability of blue- tongue virus overwintering by horizontal transmission, quantitative assessment
of the probability of bluetongue virus transmission by bovine semen and effectiveness of preventive measures, quantitative assessment of the proba- bility of bluetongue by Culicoides intro- duced via transport and trade networks.
A paper was recently published by Napp.
et al., 2010, on the quantitative assess- ment of the probability of bluetongue virus transmission by bovine semen and effectiveness of preventive measures in theriogenology.
WP6: Meetings and dissemination
One tool for the evaluation of the CA is the dissemination of knowledge. In this coordination action, major scien- tists and laboratories in bluetongue and AHS, representatives of private compa- nies and international organisations as well as political decision-makers were brought together within each work pack- age. Many of the participants and project associates are also members of various national and international societies for virology, entomology and epidemiology.
These organisations were used as dis- semination platforms. Dissemination and exploitation of the results was therefore guaranteed.
References/publications
Baylis, M., Parkin, H., Kreppel, K., Carpenter, S., Mellor, P.S., McIntyre, K.M., ‘Evaluation of housing as a means to protect cattle from Culicoides biting midges, the vectors of Bluetongue virus’, Medical and Veterinary Entomology, 2010, 24(1): 38–45.
Cêtre-Sossah, C., Madani, H., Nomikou, K., Sailleau, C., Sadaoui, H., Maan, S., Maan, N., Zientara, S., Mertens, P., Albina, E., ‘Molec- ular epidemiology of Bluetongue virus serotype 1 isolated in 2006 from Algeria’, Research in Veterinary Science, November 2010.
Maan, S., Maan, N.S., van Rijn, P.A., van Gen- nip, R.G., Sanders, A., Wright, I.M., Batten,
C., Hoffmann B., Eschbaumer, M., Oura, C.A., Potgieter, A.C., Nomikou, K., Mertens, P.P., ‘Full genome characterisation of Blue- tongue virus serotype 6 from the Nether- lands 2008 and comparison to other field and vaccine strains’, PLoS One, 2010, 5(4):
e10323.
Napp, S., Gubbins, S., Calistri, P., Allepuz, A., Alba, A., García-Bocanegra, I., Giovannini, A., Casal, J., ‘Quantitative assessment of the probability of Bluetongue virus overwinter- ing by horizontal transmission in vectors, ruminants or in both: application to Ger- many 2006–07’, Veterinary Research, 2011, 42(1): 4.
Venail, R., Mathieu, B., Setier-Rio, M.L., Borba, C., Alexandre, M., Viudes, G., Gar- ros, C., Allene, X., Carpenter, S., Baldet, T., Balenghien, T., ‘Laboratory and field-based tests of deltamethrin insecticides against adult Culicoides biting midges’, Journal of Medical Entomology, 2011, 48(2): 351–7.
Project website
http://medreonet.cirad.fr/
Keywords
orbiviruses, Bluetongue (BT), African horse sickness (AHS), Epizootic Hemorrhagic Dis- ease Virus (EHDV), diagnostic, surveillance, risk assessment
Coordinator
CIRAD
Campus International de baillaruguet TA A 15/G
34398 Montpellier Cedex 05 FRANCE
Partners
PARTNER COUNTRY CONTACT E-MAIL
AFSSA/ANSES FRANCE Stephan Zientara [email protected] IZS ITALY Annamaria Goffredo [email protected] Liverpool
University UNITED
KINGDOM Matthew Baylis [email protected]
IAH UNITED
KINGDOM Peter Mertens [email protected] SFVO SWITZERLAND Heinzpeter
Schwermer
INMV ALGERIA Hafsa Madani [email protected]
IRVT TUNISIA Soufien Sghaier [email protected]
LNEZ MOROCCO Youssef Lhor [email protected]
CVCRI TURKEY Arife Erturk [email protected]
NDRVMI BULGARIA Georgi Georgiev [email protected]
UIB SPAIN Miguel Miranda [email protected]
CRESA SPAIN Mariana Domingo [email protected]
UCM SPAIN José Manuel
Sanchez-Vizcaino
[email protected] CAVIIIPD GREECE Mickael Patakakis [email protected]
UTL PORTUGAL Isabel Fonseca [email protected]
ARC OVI SOUTH AFRICA Gert Venter [email protected]
FLI GERMANY Martin Beer [email protected]
CODA-CERVA BELGIUM Kris De Clercq [email protected] CIDC/CVI NETHERLANDS Piet Van Rijn [email protected]
DFVF DENMARK Anette Botner [email protected]
Summary
Orbivirus diseases, particularly bluetongue (BT), African horse sickness (AHS) and Epi- zootic Hemorrhagic Disease (EHD) are ser- ious current (BT) and potential future (AHS, EHD) challenges facing European agricul- ture. Bluetongue virus (BTV) is the cause of BT disease, an insect-vectored emerging pathogen of wild ruminants and livestock causing disease in sheep, goats, and cat- tle. BTV infection occurs throughout many of the temperate and tropical regions of the world, coincident with the distribu- tion of specific species of Culicoides biting midges that act as biological vectors of the virus. Since AHSV and EHDV are genetically closely related to, and are transmitted by the same insect vectors as BTV, there is a clear risk of the potential introduction of these other orbiviruses, and indeed other arboviruses, into Europe.
Although there are effective inactivated vaccines for some of the individual BTV serotypes, which are currently used in Europe, these are not currently available for all serotypes. In addition, no effective inactivated vaccines are currently licensed and available for use in Europe, for either AHSV or EHDV. Another issue with the cur- rent vaccines is that they generate an antibody response to all of the viral pro- teins, making assays that can differentiate infected from vaccinated animals (DIVA) difficult or impossible to develop.
Therefore, the major outstanding challenge of orbivirus vaccine research is to develop vaccines that can afford a broad protec- tive immune response against as many
serotypes of each virus as possible along- side a high throughput DIVA assay (e.g. an ELISA). This proposal will use a coordinated multi-partner approach to address these issues, to develop new experimental proto- type vaccines and diagnostic approaches.
Problem
Since 1998, there have been more than 12 separate introductions of BTV into Europe, involving at least 10 different virus strains belonging to eight different serotypes (types 1, 2, 4, 6, 8, 9, 16 and a new sero- type, type-25). These events have resulted in the deaths of more than two million ani- mals and have caused substantial eco- nomic losses to the agricultural economies of Europe. The outbreak caused by BTV-8, which started in the Netherlands and Bel- gium in 2006, is, by itself, the largest sin- gle outbreak of bluetongue ever recorded.
New introductions of the virus into Europe, which have been linked to climate change, have occurred almost every year since 1998, with the identification of four new virus strains in 2008 alone. New Culicoides species responsible for virus spread have also been identified in central and northern Europe, confirming that the whole of the EU is now at high risk from incursion of these diseases.
Since AHSV and EHDV are genetically closely related to, and are transmitted by the same insect vectors as BTV, there is a clear risk of the potential introduction of these other orbiviruses and other related viruses into Europe. The recent detection of BTV-9 in North Africa, EHDV in Turkey, and [ORBIVAC]
Development of vaccines for BTV, EHDV and AHSV
Acronym:
ORBIVAC Project number:
245266 EC contribution:
EUR 2 999 729