NAU researcher leads international effort to study and track brucellosis

Northern Arizona University researcher Jeff Foster is leading an international effort to study and track the spread of one of the most important infectious diseases in humans and livestock worldwide. Brucellosis infects an estimated 500,000 people and millions of animals each year - cattle, pigs, sheep, goats - resulting in long-term illness and significant economic loss, though very little is known about how the disease spreads or how to effectively control it.

Foster, an associate professor in NAU's Pathogen and Microbiome Institute, is the principal investigator on the three-year project, "Biosurveillance of Brucellosis in Azerbaijan, Georgia and Turkey." The research is supported by a $3 million grant from the Defense Threat Reduction Agency (DTRA) of the U.S. Department of Defense.

Foster will collaborate with a large team of public health, medical, veterinary and academic researchers, including nine co-principal investigators and seven other collaborators from ten institutions representing four countries - Azerbaijan, France, Georgia and Turkey - to understand how infected livestock transmit the disease to people and how to control the disease in both human and animal populations. The team's aim is to train brucellosis researchers on the latest techniques in microbiological and epidemiological research, biosafety and genomic analyses, and then to track the pathogen.

The main part of the project is to get isolates, strains of Brucella bacteria that cause brucellosis, and sequence them. Once we have the genome or genomic sequence, we can use this information for molecular epidemiology, to determine which strains of these bacteria, Brucella abortus and B. melitensis, are circulating and how the strains are related to each other."

Jeff Foster, Researcher, Northern Arizona University

Foster and his team expect to study at least 1,000 samples from infected people and animals and trace the movement of the pathogen in much the same way scientists are investigating and tracking COVID-19. "If you know where the disease is coming from, for example, if only 10 farms are responsible for 80 percent of the cases, that information has implications for how to intercede and reduce infection," he said.

Foster calls brucellosis a huge public health, livestock and agricultural issue. "We don't think about it or hear about it because it's been eradicated from the U.S. and Canada and some parts of Western Europe, but we haven't controlled it in most countries and it infects livestock herds throughout the world," he said.

The disease is especially prevalent in Western Asia and the Caucasus region. Economic instability and relaxation of regulations on livestock control in rural agricultural economies are suspected to be principal drivers of increasing infection rates since the dissolution of the Soviet Union. Because Turkey and the Caucasus region lie at the intersection of Europe and Asia, they represent a crossroads for biothreat agents. Through the DTRA, the U.S. is committed to helping with training and research on Brucella, which could be considered a potential biowarfare agent in the region.

Foster says Brucella is often found in the unpasteurized milk of animals. "Brucellosis isn't usually fatal, but it makes humans miserable, causing joint pain, persistent fever and long-term effects," he said. "It causes abortions in cattle and many other livestock, which reduces reproduction rates."

Foster believes his research will reveal where different strains occur and how they are being transmitted from animal to animal and from animal to human.

"Our targeted focus on this region will cultivate collaboration among the foremost brucellosis researchers and local experts - each providing unique skills and experience - and will create a unified approach to combatting this important disease," he said. "Moreover, we will provide a systematic approach to brucellosis management, epidemiology and research that should be readily transferable to other countries."