- Coxiella burnetii, the causative agent of Q fever
- Identification of host and bacterial factors involved in virulence
- Development of a safe and effective Q fever vaccine
- Investigation of post-vaccination hypersensitivity responses
- Expanding the guinea pig model for Q fever and beyond
Dr. Long graduated summa cum laude from Gardner-Webb University with a B.S. in 2011. She received her Ph.D. in immunology and microbial pathogenesis from West Virginia University in 2016. Here, she studied the role of regulatory T cells and microRNAs in chemical allergy at the National Institute for Occupational Safety and Health (CDC). After earning her doctorate, Dr. Long moved to Hamilton, Montana, to join Dr. Robert Heinzen’s group at the National Institutes of Health to work as an Intramural Research Training Award postdoctoral fellow. During this time, Dr. Long worked in the biosafety level (BSL)-3 laboratory researching the causative agent of Q fever, Coxiella burnetii. She investigated both bacterial and host factors required for virulence and developed a guinea pig model for infection, vaccination, and post-vaccination hypersensitivity. In 2019, Dr. Long received an Independent Research Scholar Award from NIH, allowing her to form an autonomous research group to continue her work on Coxiella burnetii.
Coxiella burnetii is a highly infectious, zoonotic bacterial pathogen that causes a debilitating febrile illness in humans called Q fever. C. burnetii is remarkably environmentally stable and typically causes Q fever via aerosol transmission. Bacterial pathogens with these attributes pose a threat to human health both due to potential bioterrorism and incidental exposure. Indeed, in 2007 a Q fever outbreak occurred in the Netherlands, resulting in nearly 4,000 human cases. This outbreak demonstrated the human health burden and the economic losses that can result from this disease, which is endemic worldwide.
Our group seeks to gain a better understanding of bacterial and host factors involved in C. burnetii virulence. Additionally, we are focused on developing a “better” Q fever vaccine. The current Q fever vaccine is highly efficacious but can cause a post-vaccination hypersensitivity response. Accordingly, the vaccine is only licensed in Australia. We seek to understand the mechanisms underlying vaccine-mediated protection and the hypersensitivity response, ultimately leading to the development of a safe, effective Q fever vaccine. We primarily use in vivo models of disease and bacterial genetic manipulation to achieve these research goals. Currently, we are developing the guinea pig Q fever model, which serves as the superior small animal model for Q fever. We seek to expand the utility of this model, which sorely lacks experimental reagents and tools, making it more useful for other researchers and disease states. Ultimately, our research goals are aimed at understanding the host-pathogen relationship between humans and C. burnetii, which may lead to the development of novel preventative measures for Q fever.
Carrie Mae Long, Ph.D., Independent Research Scholar; Mahelat Tesfamariam, B.S., Postbaccalaureate Intramural Research Training Award Fellow; Picabo Binette, B.S., Postbaccalaureate Intramural Research Training Award Fellow
Long CM, Beare PA, Cockrell DC, Fintzi J, Tesfamariam, M, Shaia CI, Heinzen RA. Contributions of lipopolysaccharide and the type IVB secretion system to Coxiella burnetii vaccine efficacy and reactogenicity. npj Vaccines. 2021 Dec;6(1).
Long CM, Beare PA, Cockrell DC, Larson CE, Heinzen RA. Comparative virulence of diverse Coxiella burnetii strains. Virulence. 2019 Dec;10(1):133-150.
Beare PA, Jeffey BM, Long CM, Martens CM, Heinzen RA. Genetic mechanisms of Coxiella burnetii lipopolysaccharide phase variation. PLoS Pathog. 2018 Feb 26;14(3):e1006922.
Cockrell DC, Long CM, Robertson SJ, Shannon JG, Miller HE, Myers L, Larson CL, Starr T, Beare PA, Heinzen RA. Robust growth of avirulent phase II Coxiella burnetii in bone marrow-derived murine macrophages. PLoS One. 2017 Mar 9;12(3):e0173528.