A Royal Veterinary College (RVC) expert is in Mongolia to join a crisis management mission in response to critically endangered saiga antelope dying off in the country.
Some 1052 Saiga tatarica mongolica – a critically endangered sub-species of saiga – have been found dead in Mongolia’s western Khovd province over a third of the range so far, out of a total population of around 10,000. Mortalities are expected to be higher by the end of the epidemic.
Samples taken from carcasses were positive for peste des petits ruminants (PPR) infection, a lethal viral disease with plague-like impact on domestic herds. It can kill up to 90% of animals it infects.
This wildlife mortality follows an outbreak of this emerging disease in Mongolia for the first time ever in sheep and goats in September 2016 in Khovd. Despite mass vaccination it seems the virus is still active and could have devastating impacts on this largely nomadic pastoral society and the rich wildlife species which are susceptible.
This event follows another devastating mass mortality of some 220,000 saiga in Kazakhstan in 2015 which attracted global attention.
Richard Kock, Professor of Wildlife Health and Emerging Diseases at the RVC, has expertise in veterinary epidemiology, ecosystems health and vaccinology. The Crisis Management Committee mission he has joined is a joint United Nations Food and Agriculture Organization and World Organisation for Animal Health (OIE) initiative.
Professor Kock is visiting the affected area and will provide feedback to the Mongolian government and international community. Along with the rest of the Crisis Management Committee, he will advise on what can be done to reduce the disease impact on the saiga.
The Committee will provide technical expertise to support Mongolian officials in their investigation of PPR among wild animals and its potential impact on the current PPR situation in livestock. The team intends to identify any interactions between wildlife populations with food production animals relative to the risk of introduction and spread of PPR.
Professor Kock and the team will support Mongolian officials in their assessment of the epidemiological situation and outbreak investigation methods. They will also help local officials coordinate with other sectors to investigate the suspected PPR morbidity and mortality events in Mongolian wildlife species. The Committee will support the Mongolian veterinary services to ensure the diagnostic material available is sent to the Global Reference Laboratory for PPR, which is at Pirbright Institute in the UK, and to CIRAD in France for confirmation of the viral diagnosis.
Commenting on the situation in Mongolia, Professor Kock said: “Critical communication efforts must be made to let Mongolian herders know the risks of the PPR virus spilling between saiga and livestock. We are still unravelling these devastating outbreaks in Kazakhstan and we have learned that these events are requiring a particularly high level of international cooperation and inclusion of the FAO OIE and world reference laboratories to ensure full understanding of the epidemiology.”
The FAO’s Chief Veterinary Officer Dr Juan Lubroth has underlined that a regional strategy to contain and eradicate PPR needs to implemented and resources made available to prevent further spread of the virus in Mongolia, as well as in Kazakhstan and China where outbreaks were first reported in recent years.
The FAO and the OIE are leading a multinational effort to eradicate PPR, which can have devastating food-security and economic impacts, by 2030. 80% of the world’s estimated 2.1 billion small ruminants live in affected regions and constitute an important asset for a third of poor rural households in developing countries. PPR, first identified in Côte d’Ivoire in the 1940s, is now reported in over 75 countries.
While wildlife have long been considered potentially vulnerable to the virus, relatively few actual cases of PPR infection have been documented, and never in free-ranging antelope. The dead saiga are highly suggestive that there was a spillover of virus from domestic animals, which were affected by PPR in the summer of 2016. 11 million vaccines were applied to control the spread of the disease, which had been reported in the country for the first time. Saiga and small livestock share common grazing areas as livestock systems are based on traditional nomadic pastoralism.
Efforts are ongoing to investigate the situation on the ground, geared in particular to collecting more diagnostic materials and conducting additional tests to investigate possible other causes, including the bacterial infection Pasteurella multocida, which was the proximate cause of death of hundreds of thousands of saiga in Kazakhstan in 2015.
RVC scientists and collaborators are undertaking ongoing investigations of that mass mortality. Scientists are looking for underlying triggers, including viruses, climate and other factors to explain this extraordinary event where over 90% of the population died over a few weeks, affecting some 220,000 animals spread over an area the size of England.
Saiga in Mongolia are not truly migratory like their cousins in Kazakhstan but are nomadic with an extensive range of about 13,000 km2, with seasonal movements in autumn for breeding and spring for calving. Other wild species at risk include the goitered and Mongolian gazelle, mountain ibex and Bactrian camel.