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Molecular epidemiology of Bacillus anthracis: novel data and techniques for local surveillance in Tanzania

Periodic Reporting for period 1 - MEBA (Molecular epidemiology of Bacillus anthracis: novel data and techniques for local surveillance in Tanzania)

Reporting period: 2015-11-02 to 2017-11-01

Anthrax is a neglected zoonotic disease that remains endemic in many developing countries worldwide. In rural communities in northern Tanzania, regular cases and outbreaks of anthrax in livestock and people have devastating impacts on both health and livelihoods. Understanding and controlling the spread of Bacillus anthracis, the spore-forming bacterium that causes anthrax, in endemic settings is currently impeded by a lack of data on its occurrence and distribution, its genetic diversity, and on its transmission dynamics among various host species and the environmental reservoir. The aim of this fellowship was to improve our understanding of the epidemiology of anthrax in endemic settings, focusing on the Ngorongoro Conservation Area (NCA) as a model system. Overall, this Marie Curie Fellowship has resulted in the development of a strong One Health surveillance platform for anthrax, making important connections between the human and animal health sectors. The substantial samples and data that have been collected through this platform have contributed significantly to our understanding of the occurrence and impact of anthrax in the NCA, while paving the way for more in-depth molecular epidemiological studies to better understand transmission. These analyses - which are currently underway - will help to inform anthrax management and control through the important stakeholder networks that have been developed during this project.
During this fellowship, I established molecular diagnostic protocols (qPCR) at Kilimanjaro Clinical Research Institute (KCRI) in Moshi, northern Tanzania, following validation in partnership with collaborators at the University of Pretoria (UoP) in South Africa. Eight technicians at KCRI were trained in these protocols, in addition to colleagues from two other higher education institutions in Tanzania with an interest in anthrax research. I also established a surveillance platform to collect diagnostic material and data from suspect cases of anthrax in animals. I contributed to strengthening the capacity of veterinary health professionals in the NCA for recognizing anthrax and collecting samples while taking appropriate safety precautions. Moreover, through collaborations with my secondment organization of Public Health England, we extended this training to human health professionals.

From April 2016 to October 2017, samples from a total of 348 livestock and wildlife carcasses were collected and tested for anthrax at KCRI. Two thirds of the cases tested were confirmed positive (n =231). Test results were shared regularly with the Director of Veterinary Services, the Ministry of Agriculture, local veterinary authorities, and project collaborators. A subset of the samples collected have been sent to UoP for bacterial culture and DNA extraction, which will allow for whole genome sequencing and in-depth phylogenetic analyses. We also documented more than 130 suspect human cases between June 2016 and October 2017, based on the classic skin lesions associated with cutaneous anthrax. Ethical approval is now in place to initiate sample collection from human cases for diagnostic confirmation.

I have presented this work at the scientific conferences of the Tanzania Veterinary Association in both 2016 and 2017, as well as the Biology of Anthrax conference in 2016. A podcast on how NCA community members experience anthrax was also published on “Naturally Speaking”, the blog of my host Institute at the University of Glasgow.
This fellowship has yielded unprecedented data and diagnostic material for improving our understanding of the occurrence and transmission of Bacillus anthracis in endemic settings. Another important achievement of this fellowship was the establishment of important collaborations and networks with key stakeholders, from the community level through to various levels of government and NGOs, including policy makers. This was primarily through a series of three knowledge exchange workshops that I led, involving a total of nearly 100 participants, which had the goals of coming to a shared understanding of anthrax in the NCA, identifying current barriers to its surveillance and control, and considering potential solutions for overcoming these challenges. These activities have led to a greater knowledge and awareness of the disease, both within affected communities and at the national level, and the identification of key times of year and hot-spot areas that would be most effective for targeted vaccination. Overall, the outcomes of this fellowship have led to securing a further 3 years of fellowship funding (BBSRC Future Leader Fellowship) for ongoing research in this area, and will feed into the national strategy for anthrax control in Tanzania.
Maasai communities in Ngorongoro Conservation Area, northern Tanzania where anthrax is endemic