Novel molecular approaches for understanding the epidemiology of endemic anthrax

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This project will study anthrax, a bacterial disease of people and animals, in developing-country settings where the disease is widespread. While anthrax is most commonly known as an agent of bio-terrorism, it in fact remains a common disease in many poor rural areas, particularly in sub-Saharan Africa. It primarily affects ruminant livestock and wildlife, wherein the disease manifests as sudden deaths. The bacterial spores that cause anthrax can also secondarily infect humans. Anthrax can take one of three forms in people, depending on the route of transmission: a less serious from causing skin lesions, and two more severe forms affecting the digestive and respiratory systems. All three forms can be fatal if left untreated. The greatest impacts of this disease are felt by livestock-keeping communities, where animal losses represent significant costs for livelihoods and food security, and result in risk of human exposure.This project will be based in the Ngorongoro Conservation Area in Tanzania, East Africa. This area - rich in a variety of wildlife - is home to Maasai pastoralists who depend almost entirely on livestock for food and income. Anthrax is a major issue for both animal and human health in this area. Livestock losses occur regularly, with approximately a quarter of households reporting suspected cases in their herds over the past two years. Additionally, more than 40 cases of human anthrax - including five deaths - were seen at the regional hospital in the second half of 2016 alone. In this unique study system, I will apply novel techniques to study the genetic characteristics of bacteria obtained from affected animals and people. These analyses will allow me to determine the main sources of infection for animals and people, and how these cases are linked.The main objective of this study is to determine how the bacterium that causes anthrax is spread and transmitted, particularly during outbreaks. This includes assessing how often transmission occurs between different host species, and identifying the main sources of risk for livestock and people. I will train a team of local human and animal health professionals to conduct in-depth case investigations. The team will collect detailed data and samples during outbreaks. This training will contribute not only to the project, but will strengthen local capacity to handle this and other animal diseases. To ensure that affected community members, health practitioners, and local and national policy makers are involved at all stages of the research, I will invite representatives from these groups to attend annual workshops that I will host. These will maximise the benefits of my research by increasing disease awareness, improving connectivity among key individuals in the community and government, and ensuring that project results are able to feed directly into policy.The samples collected from the different host species during this project will serve as a source of bacterial DNA that can be used to track transmission, similarly to DNA fingerprinting in forensics investigations. The DNA from these various sources (e.g. livestock, wildlife and people) will be fully analysed to obtain the genome of each individual bacterium. These data will provide incredibly high-resolution information that will allow me to reconstruct chains of transmission amongst affected species, determine associations between particular strains and different host species, and understand whether individual cases may be the result of infection from multiple sources.I will use the novel information generated by my study to provide management and control recommendations for anthrax in rural livestock-keeping communities, leading to enhanced animal and human health, and improved food security and poverty alleviation through reduced production losses.