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One Health study of tick-borne diseases in Mongolia

Asia & Australasia

To better understand the epidemiology of tick-borne disease in Mongolia, a comprehensive seroprevalence study was conducted investigating exposure to Anaplasma spp. and spotted fever group (SFG) Rickettsia spp. in nomadic herders and their livestock across three provinces from 2014 to 2015.

Dr. Michael von Fricken spent a year living in Ulaanbataar as a postdoc with Duke University, under Dr. Greg Gray, working alongside veterinarians from the Institute of Veterinary Medicine and the National Center for Zoonotic Diseases in Mongolia. Now an Assistant Professor in the Department of Global and Community Health at George Mason University, von Fricken and his colleagues recently published their findings in Acta Tropica.

This study is unique given the under-studied target population of Mongolian herders, and the diverse landscapes covered, ranging from the arid Gobi region to the south to the Central Steppe and Altai Mountains to the north. In this study, von Fricken and his team tested serum for antibodies indicative of previous exposure to Anaplasma spp. and SFG Rickettsia spp.

“By relying on One Health methodologies, we are investigating the broader implications for risk of disease transmission. That includes not just human health, but that of livestock and the environments they live in,” von Fricken explained. “This makes for much richer datasets that can be used to identify key factors driving disease exposures that may be missed using siloed research approaches.”

The research team detected high rates of previous Anaplasma spp. and SFG Rickettsia in their human and livestock samples. Humans were significantly more likely to have been exposed to a tick-borne disease in the northern provinces of Mongolia compared to samples collected from the Gobi Desert region.

“Findings from this study make a case for expanded tick-borne disease research in northern Mongolia, as it appears to be a hot spot for pathogen exposure, which is something we plan to investigate with partners in Mongolia.”

Article: Estimated seroprevalence of Anaplasma spp. and spotted fever group Rickettsia exposure among herders and livestock in Mongolia by Michael E. von Fricken, Sukhbaatar Lkhagvatseren, Bazartseren Boldbaatar, Pagbajab Nymadawa, Thomas A. Weppelmann, Bekh-Ochir Baigalmaa, Benjamin D. Anderson, Megan E. Reller, Paul M. Lantos and Gregory C. Gray, published in Acta Tropica (2018) vol. 177, pp. 179-185, doi: 10.1016/j.actatropica.2017.10.015

[SOURCE: George Mason University]

Roadmap to combat bovine and zoonotic tuberculosis

Global

The Roadmap for Zoonotic Tuberculosis was launched at the 48th Union World Conference on Lung Health, which took place in Guadalajara, Mexico, 11-14 October 2017. Four partners in health, the World Health Organization (WHO), the World Organisation for Animal Health (OIE), the Food and Agriculture Organization of the United Nations (FAO) and the International Union Against Tuberculosis and Lung Disease (The Union) have joined forces to develop the roadmap and address the major health and economic impact of this disease.

Bovine TB is most often transmitted to humans through food consumption, usually non-heat-treated dairy products or raw or improperly cooked meat from diseased animals. Direct transmission from infected animals or animal products to people can also occur.

“This multidisciplinary roadmap represents a milestone in the fight against TB in both people and animals,” said Paula I Fujiwara, Scientific Director, The Union. “Better technologies, better science and better governance for affected communities bearing the bovine TB burden in poorer rural areas must become the new mantra if we are to get on the path to eliminating TB absolutely everywhere”.

Zoonotic TB is largely hidden. The advanced laboratory tools are required to diagnose zoonotic TB are frequently unavailable. The disease is resistant to pyrazinamide – one of the standard first-line medications used to treat TB. Patients are therefore often misdiagnosed and may receive ineffective treatment.

“We must recognise the interdependence of the health of people and animals in the fight against TB. Specifically, bovine TB, caused by Mycobacterium bovis, affects cattle, threatens people’s livelihoods and results in major economic and trade barriers, as well as posing a major risk to food safety and human health,” said Berhe Tekola, Director of the FAO Animal Production and Health Division.

The roadmap articulates 10 priority actions that human and animal health actors should take, and defines milestones for the short- and medium-term.

See: Roadmap for Zoonotic Tuberculosis

[SOURCE: FAO]

Modified virus shows promise as an ASF vaccine

Global

Researchers have found that deleting a gene of African swine fever virus (ASFV) reduces its ability to cause infection and protects against a strain of the virus that causes severe disease.

In the study, published in the Journal of Virology, scientists at The Pirbright Institute deleted an ASFV gene that codes for a protein (DP148R) thought to play a role in suppressing the pig immune system. The resulting modified virus was still able to replicate, but showed a dramatically reduced ability to cause infection; the pigs all survived and only displayed mild clinical signs. After being exposed to the modified strain, the pigs were protected against further infection from a natural strain of ASFV.

Dr Linda Dixon, leader of the ASF group at Pirbright, said: “Now that we have shown the modified virus has the ability to protect pigs against a natural strain, the next steps will be to make more gene deletions that will reduce the clinical signs exhibited by pigs after vaccination.

“We will also be investigating the precise role the protein plays during infection. This information will help us understand how it interacts with the host immune system and if the protein directly prevents immune processes or if it has other roles we haven’t yet identified. Knowing more about the gene and protein will make it easier for us to modify the virus further and create a vaccine that is effective and safe.”

ASF has no vaccine. The disease is currently spreading further across Europe, with outbreaks recently described in Romania for the first time. ASF can be very difficult to identify, as it displays similar clinical signs to other pig diseases, with the most harmful strains killing pigs before specific signs become apparent. In regions where infected wild boar are present, transmission of ASFV to domestic pigs complicates control of the disease.

Current prevention strategies focus around import controls and the education of farm owners on ASF and biosecurity to prevent infection and diagnose rapidly. However, these tools are currently not robust enough to stop the disease spreading across Eastern Europe and Russia.

The Pirbright research has shown that the modified virus could potentially be used as a component of a live attenuated vaccine. These vaccines have recently been reviewed in an article published in Vaccines by the European Union ASF Expert Working Group, which includes Dr. Linda Dixon.

The experts established that live attenuated vaccines are the most promising and best positioned candidates for use in the future against ASF. Although there are still important issues such as safety and effectiveness that need resolving before these vaccines are available commercially, Pirbright scientists anticipate further research on this candidate could lead to the development of an ASF vaccine.

Article: Deletion of the African swine fever virus gene DP148R does not reduce virus replication in culture but reduces virus virulence in pigs and induces high levels of protection against challenge by Ana L. Reis, Lynnette C. Goatley, Tamara Jabbar, Pedro J. Sanchez-Cordon, Christopher L. Netherton, Dave G. Chapman and Linda K. Dixon, published in Journal of Virology, online 4 October 2017, doi: 10.1128/JVI.01428-17

[SOURCE: The Pirbright Institute]

Veterinary experts meet to advance animal health and productivity for African farmers

Africa & the Middle EastGlobal

Veterinary experts meet to advance animal health and productivity for African farmers

 21 September 2017 – Animal health experts from Africa and the Middle East met in Abuja, Nigeria on 12-14th September to agree common research priorities for Africa and explore sharing of resources and facilities to maximise the impact of research in advancing the health and productivity of livestock.

 Sub-Saharan Africa is home to some of the largest livestock populations in the world and has the highest density of impoverished livestock farmers. It is estimated that more than 50% of the people in this region live on less than $1 a day, depend on livestock which provides approximately 45% of the total family income. Livestock are an essential asset to rural communities, and the health of livestock is critical to achieving food security in regions where there is exceptionally high incidence of livestock and human disease. At the same time, some parts of Sub-Saharan Africa are also seeing increasing demand for quality livestock products from its growing population, which is becoming more urbanised and affluent. Research is needed to find solutions to the problems experienced by Africa’s livestock farmers, including production diseases and major infectious diseases. Infrastructure and networks are needed to bring the solutions to the field.

 This strategic veterinary research funders and programme-owners summit organised by STAR-IDAZ and CABI represents an excellent example of how together we could continue bringing innovative solutions to animal diseases and zoonoses in Sub-Saharan Africa,” said Theo Kanellos, Director of Business Development and Alliances of Zoetis. “Forging effective public/private collaborations in Africa will significantly accelerate the advancement of health and productivity of livestock which are an essential asset to rural communities and critical to food security in areas with high animal and human disease incidence.” Zoetis is leading several such collaborations and initiatives in Sub-Saharan Africa.

 The meeting was followed by the Nigerian Animal Health Research Forum, 15th September. This brought together key persons from animal health research, the veterinary profession and industry in Nigeria to coordinate epidemiological surveys and veterinary laboratory activities for diagnosis and control of animal diseases, and increase collaboration between research, farming and industry. The meeting decided to form a Nigerian Animal Health Research Network chaired by Dr David Shamaki of the National Veterinary Research Institute, Vom. Dr Shamaki said “Coordination of research will make the best use of scarce resources and help develop solutions to problems in the livestock sector which is vital to the lives of many people in Nigeria and across Africa”.

 Dr Alex Morrow, Chair of the International Research Consortium said “These meetings, organised with the support of Zoetis, will help move forward coordination of the research effort to find innovative solutions to the many disease challenges of the livestock sectors, some of which are unique to Africa and the Middle-East. By working together we can speed up the development of new and improved disease control strategies which are essential to protect animal and human health

 STAR-IDAZ IRC (Global Strategic Alliances for Coordination of Research on Major Infectious Diseases of Animals and Zoonoses – International Research Consortium) is a global initiative that coordinates research programmes, at the international level, in animal health. It strengthens the links between and reduces the duplication of the global animal health research effort on high priority animal health issues, maximises the efficient use of expertise and resources, and accelerates coordinated development of control methods.

 About:

STAR-IDAZ IRC (www.star-idaz.net) is supported by an EU funded project.

 National Veterinary Research Institute, Vom, Plateau State, Nigeria (www.nvri.gov.ng/) committed to research excellence and the production of standard quality vaccines for the livestock industry.

 Zoetis (www.zoetis.com) is the leading animal health company, dedicated to supporting its customers and their businesses. Building on more than 60 years of experience in animal health, Zoetis discovers, develops, manufactures and markets veterinary vaccines and medicines, complemented by diagnostic products, genetic tests, biodevices and a range of services.

 CABI (www.cabi.org) is an international not-for-profit organisation that improves people’s lives by providing information and applying scientific expertise to solve problems in agriculture and the environment. Our 48 member countries guide and influence our core areas of work, which include International Development and Publishing.