Researchers have made a significant breakthrough in examining the spread of Peste des Petits Ruminants (PPR), an animal disease targeted for global eradication.
They found that repeated vaccination campaigns targeting production systems acting as viral reservoirs would be the most effective way of eradicating the disease.
PPR is a deadly disease of sheep and goats threatening the livelihoods of farmers predominantly in Africa, the Middle-east and Asia, with some cases also recently reported in Bulgaria. The Food and Agriculture Organisation of the United Nations and the World Organisation for Animal Health have launched global efforts to eradicate this disease within the next 15 years. So far, only two infectious diseases have ever been eradicated, smallpox in humans and rinderpest in cattle.
The PPR eradication strategy relies on mass vaccination campaigns. Although a vaccine providing lifelong protective immunity exists, such campaigns are costly and logistically challenging, due in particular to the mobility and the lack of accessibility of small ruminant flocks, and the lack of accurate census data.
An international team, led by the RVC’s Dr Guillaume Fournié, and initiated by CIRAD’s Dr Francois Roger, worked in Ethiopia to combine the results of a nation-wide serological survey with a dynamic model which simulated PPR spread. With this information, the team identified the pastoral production system as a reservoir of infection from which the virus could spread to other small ruminant populations in Ethiopia and neighbouring countries. They were able to estimate the vaccination coverage that would be required to suppress viral transmission.
Dr Guillaume Fournié, Senior Research Fellow at the RVC, said:
“Identifying high-risk populations and tailoring vaccination strategies to local epidemiological contexts is essential. This would not only reduce the cost of PPR eradication, but also increase the likelihood of success by setting more achievable vaccination coverages.”
Dr François Roger, Co-director of the ASTRE Joint Research Unit at CIRAD, added:
“PPR causes huge economic losses and a very large number of families in low- and middle-income countries are at risk of losing their livelihoods, food security and employment. Considering the limited budgets allocated to the control of PPR and the numerous field constraints, decision effective making-tools are essential”.
About the Royal Veterinary College
- The Royal Veterinary College (RVC) is the UK's largest and longest established independent veterinary school and is a constituent College of the University of London. The RVC offers undergraduate, postgraduate and CPD programmes in veterinary medicine, veterinary nursing and biological sciences.
- It is currently the only veterinary school in the world to hold full accreditation from AVMA, EAEVE, RCVS and AVBC.
- In 2017, the RVC received a Gold award from the Teaching Excellence Framework (TEF) – the highest rating a university can receive. A research-led institution, in the most recent Research Excellence Framework (REF2014) the RVC maintained its position as the top HEFCE funded veterinary focused research institution.
- The RVC also provides animal owners and the veterinary profession with access to expert veterinary care and advice through its teaching hospitals; the Beaumont Sainsbury Animal Hospital in central London, the Queen Mother Hospital for Animals (Europe's largest small animal referral centre), the Equine Referral Hospital, and the Farm Animal Clinical Centre located at the Hertfordshire campus.
About the French Agricultural Research Centre for International Development:
- The Agricultural Research Centre for International Development (CIRAD) is a French public organisation working for the sustainable development of tropical and Mediterranean regions.
- ASTRE (Animals, Health, Territories, Risks and Ecosystems) is a CIRAD unit working to foster an integrated animal health approach. The aim of the UMR is to improve animal health, public health and food security in the South, notably against a backdrop of global change and transitions within socio-ecosystems. The main challenge is to develop an integrated health approach: inter-sectoriality and interdisciplinarity centring on animals, ecosystems and territories, in line with the One Health and EcoHealth approaches.
- CIRAD’s unit ASTRE is National, OIE/FAO, EU reference laboratory for PPR:
- Training and proficiency testing on PPR diagnostic methods, Quality control of vaccines, Provision of reference material, Development of new diagnostic methods, Expert support to veterinary services, Confirmation of diagnosis, Quality control of bank of viral strains, genome sequencing and phylogenetic analyses, PPR transmission dynamics and modelling, expert missions for OIE and FAO to support PPR-GEP (global eradication programme) : diagnostic, vaccine and vaccination, epidemiology, modelling, surveillance, socio-economy, integrated approaches, training and education · https://www.cirad.fr/en