Can Zebras Help Us Understand a Bioterrorism Agent?

ALBANY, N.Y. (Aug. 15, 2018) – Wendy Turner, an assistant professor of biological sciences in the College of Arts & Sciences (CAS), has received $2.5 million from the National Science Foundation to study anthrax transmission among African wildlife.

Anthrax disease, which can be fatal in both humans and animals, is caused by the soil bacterium Bacillus anthracis (B. anthracis). When purified in a lab, the bacterium becomes a bio-terrorism agent most known for its white, powder-like appearance. According to Turner, naturally-occurring anthrax is a larger problem than most realize.

Why Anthrax?

Though many people think of the substance used in the 2001 attacks in which anthrax spores were transported via mail, anthrax has been a deadly epidemic in wildlife and livestock since long before humans began processing it in a lab for intentional harm. When not in a host, the pathogen forms spores that can survive in soil for decades, awaiting contact with a new host. Additionally, it can be transferred from livestock to humans via infected meat or animal hides.

“Anthrax is a naturally occurring pathogen that’s existed all over the world, including in the U.S., for much longer than people have been tinkering with it,” Turner said. “Because it is incredibly deadly among wildlife and can be transferred to humans, it’s important to have a better understanding of its transmission and evolution.”

Turner also notes that past assumptions about anthrax warrant further investigation. She asserts that the pathogen is not globally diverse; Genetically, it’s about 99% similar no matter where it occurs. Because of this, she says, there is an assumption among scientists that anthrax is the “perfect” pathogen: It’s highly lethal and able to infect a wide diversity of hosts, and therefore does not need to adapt in any way.

However, ongoing research by Turner and colleagues indicates that the pathogen’s diversity can and does change over time in some, but not all, ecosystems. Therefore, there is “something interesting going on” among locations that scientists don’t yet understand, possibly caused by differences in the pathogen’s environment or its relationships with specific host species.

The Process

Turner and her team of two doctoral students, an undergraduate student, and a post-doctoral researcher traveled from UAlbany to Africa this summer for the first part of their research. They are comparing the dynamics of the anthrax pathogen found in zebras and kudus (a species of antelope), known to be primary host species for anthrax, in two national parks with vastly different environments: Etosha National Park in Namibia and Kruger National Park in South Africa.

The team will continue to conduct field and laboratory experiments to test for differences among B. anthracis strains that could affect their ability to survive in the environment or to kill a host more quickly. They will use 50 years of pathogen samples to see if and how the pathogen’s genome has changed over time in different environments. Additionally, they fit wild zebras and kudus with GPS collars, as well as tested if the animals were recently exposed to B. anthracis (leaving an immunological signature in the blood), and are comparing host populations for genetic evidence of resistance against the pathogen. This type of information, Turner says, will help determine whether the absence of disease is a result of a lack of exposure, or a developed resistance to the disease. The team can then simultaneously study the anthrax pathogen, its hosts, and the environment over the course of the four-year project to discover what underlying differences exist between study areas that may affect the local character of the disease.

According to Turner, the chosen parks are ideal locations for study because of their differences in how and when anthrax outbreaks occur, and because both areas consider anthrax a “natural element” of the ecosystem and therefore managers do not attempt to stop its transmission. In other locations around the world, Turner says, as soon as an outbreak occurs, immediate actions are taken in an attempt to stop it, making it difficult to understand the epidemiology. Working at Etosha and Kruger will allow the team to study the dynamics of this disease in its natural environment.

The studies, which take place in areas of the parks with both high and low incidences of anthrax, are expected to provide new insight into the roles that the environment, pathogen, and hosts play in the ecology and evolution of the disease. In addition to the team from UAlbany, scientists from the University of Maine, University of Pretoria in South Africa, University of Namibia, University of Oslo in Norway, and University of Hohenheim in Germany and both national parks are participating in the project.

The Long-Term Impact

A better understanding of this complex disease system could facilitate the development of predictive tools to better manage public health and related policies in developing countries, Turner says. Additionally, this type of information is useful for when anthrax outbreaks occurs in humans, because “If you can understand what’s happening in animals, you can also understand the likely source of human infection.”

“This grant allows Dr. Turner and her team to investigate a disease that has been known since ancient times but has acquired attention in recent years as an agent of potent biological warfare,” said CAS Dean Edelgard Wulfert. “Her research has not only important implications for public health but may also generate new insights into bioterrorism.”

The team will engage in public outreach, including a blog that will share the team’s perspectives on the scientific process at different career stages, research findings and experiences.

Photos by Wendy Turner

For more news, subscribe to UAlbany's RSS headline feeds