Flies creating buzz

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Researchers studying how to eliminate spread of disease, especially from the common fly

Antimicrobial resistance remains one of the biggest threats to public health despite decades of efforts to slow down the selection and transfer of resistance through judicious use of antimicrobials.

A research team lead by Dr. Chengming Wang, a professor in the Department of Pathobiology in Auburn University’s College of Veterinary Medicine, is conducting a multi-pronged program of federally funded research that is focused on zoonoses — diseases that are transferred from animals to humans — and antimicrobial resistance, with a goal of developing more effective mitigation.

Wang is assisted in this research by Dr. Kenneth S. Macklin from the Auburn College of Agriculture and other colleagues in the College of Veterinary Medicine: Drs. Stuart Price, Russel Cattley, Paul Walz, Terri Hathcock, Anil Poudel, Anwar Kalalah, Subarna Barua, Folasade Adekanmbi and Md Monirul Hoque. He also is working with Drs. Patrick  Butaye and Patrick Kelly at Ross University School of Veterinary Medicine.

“We are looking at several areas of research as it relates to disease transmission and antimicrobial resistance,” Wang said. “We are studying various ways that these antibiotic resistant bacteria are transmitted, what are the most common ways that they are transmitted, and what vaccines can be most effective in treating against these pathogens that are resistant to many commonly used antibiotics.”

Surveillance for antimicrobial resistance is one of the research studies underway by Wang and his colleagues.

“Surveillance of antimicrobial resistance is critical for identifying emerging resistance and for developing and validating the effectiveness of prevention and control strategies,” Wang said. “A number of federal agencies are supporting research in this area that seeks to isolate and study such bacterial pathogens as Salmonella, Campylobacter, Escherichia coli and Enterococcus isolated from meat, food animals and human clinical samples.”

Wang’s team studies the transfer of these bacteria by common flies.

“Flies are common in and around livestock operations, easily making effective contacts with animals, manure and the environment,” Wang said. “Flies are not only associated with agricultural environments but reside also in urban locations where they contact humans and their environment as well as their waste. It has recently been shown that flies not only carry antimicrobial-resistant bacteria, but that their intestines provide a suitable environment for horizontal transfer of antimicrobial resistance genes.

“Flies are well-known vectors of bacterial pathogens, but there are little data on their role in spreading microbial community and antimicrobial resistance. This work is structured to provide the preliminary data on the possible dissemination of antimicrobial resistance between animals and human beings by flies.”

Another area of Wang’s research examines Rickettsia felis, an emerging human pathogen causing flea-borne spotted fever.

Although found in a wide range of arthropods including fleas, ticks, mites and lice, the cat flea is currently believed to be the most likely primary vector of R. felis, according to Wang.

“There is growing evidence that mosquitoes might be involved in R. felis transmission,” Wang writes about his findings. “Our results show that R. felis occurs in mosquitoes in the United States. The growing reports of R. felis occurring in mosquito species around the world and the known role of mosquitoes in transmitting a wide range of very important human and animal pathogens indicate an urgent need for further studies to determine the role mosquitoes might play in the epidemiology of R. felis infections in people.”

Raw meats used as animal feed sources also comprise an area of zoonoses that Wang and his team are investigating.

“Advocates of raw meat diets claim various health benefits for dogs, and while none of the purported benefits have been validated, owners of raw meat fed animals stand by their convictions,” Wang writes. “But a two-year study conducted by the U.S. Food and Drug Administration found that raw pet food is more likely than other types of pet food to carry bacteria, including salmonella and listeria monocytogenes.

“As a result, FDA issued a public health warning about the risks of raw pet food diets and both the American Animal Hospital Association and the American Veterinary Medical Association officially recommend against feeding raw meat-based diets to dogs,” Wang said. “Our research is making deeper investigations into this condition, which is shown to harbor antimicrobial resistant bacteria.”

In addition to their investigation of antimicrobial resistance bacteria and its transmission, Wang and his team also are interested in learning more about available antibiotics and improving the effectiveness of those known to be effective in mitigating bacterial infections. Wang is particularly interested in the antibiotic colistin.

Colistin is a last-resort drug used to treat infections caused by multidrug-resistant Gram-negative bacteria that have developed resistance, Wang explains.

Wang writes: “Antimicrobial resistance to colistin has emerged worldwide, threatening the efficacy of one of the last-resort antimicrobials used for the treatment of infections caused by multidrug-resistant Gram-negative bacteria. Until 2016, only mutation-mediated resistance was described in bacteria from humans and animals, but it is now clear that other common bacteria are colistin resistance.”

Colistin has been around since the late 1940s. Although it is used to treat a number of human illnesses, such as pneumonia, it is largely reserved for agricultural and veterinary medicine use because of the possible side effects.

“Colistin has many possible side effects,” Wang said. “It can affect the kidneys, it can cause neurological problems and it can produce muscle weakness and even breeding problems. But it has long been used when the bacteria proved resistant to other antibiotics.”

As recent as 2017, the reliable last resort colistin began showing ineffectiveness in combating antimicrobial resistant bacteria.

Wang and his research team are among a rapidly growing number of scientists focused on research involving the transmission of diseases and the development of ways to mitigate or eliminate them. The spread of disease from animal to human is an important area within this vast research, and many of the treatments that have been effective in the past are beginning to lose their strength.

“Antimicrobial resistance is rising globally at an alarming rate,” Wang notes. “Our research hopefully will make new discoveries that increase our knowledge and help to keep us winning the battle against zoonotic diseases and their transmission.”

Auburn professors part of collaborative project to strengthen STEM graduate programs for underrepresented minorities

In 2014, researchers from Auburn University joined with Tuskegee University and Alabama State University in a collaborative effort to develop, implement and study unique and innovative models that identify, eliminate or mitigate factors that impact persistence in STEM (science, technology, engineering and mathematics) graduate programs for underrepresented minorities (URM). The study, titled “Tuskegee Alliance to Forge Pathways to STEM Academic Careers” (T-PAC), was funded by the National Science Foundation (NSF). The total grant award across the three institutions was $2,593,384; Auburn’s portion of the award was $821,702.

Dr. Melody Russell, a professor in the College of Education’s Department of Curriculum and Teaching, served as Auburn’s principal investigator (PI) for the grant. Co-PIs from Auburn included Dr. Jared A. Russell (School of Kinesiology), Dr. Oladiran Fasina (Department of Biosystems Engineering) and Dr. Curtis Shannon (Department of Chemistry and Biochemistry).

“This interdisciplinary and collaborative project that focuses on broadening participation and promoting equity and social justice in STEM for traditionally underrepresented groups is important for many reasons. And for me it has special relevance because it has long been my primary area of research, as well as my passion,” said Dr. Melody Russell.

The award comes from the NSF’s Alliances for Graduate Education and the Professoriate (AGEP) program. The AGEP Transformation track targets strategic alliances of institutions and organizations to develop, implement and study innovative evidence-based models and standards for STEM graduate education, postdoctoral training and academic STEM career preparation that eliminate or mitigate negative factors and promote positive practices for URM.

“NSF’s investment in the project reflects its commitment to broadening the participation of underrepresented minorities in the STEM fields,” said NSF Program Director Dr. Mark Leddy at the outset of the study. “This AGEP Transformation project draws on the expertise of three Alabama universities with a strong record of federally funded grants to advance a new STEM education model for underrepresented minorities. It will lead toward increasing the diversity of academe and the broader STEM workforce.”

The AGEP project ultimately seeks to enhance the graduate experience, promote retention for students from underrepresented groups, and increase the number of those underrepresented in the STEM professoriate.

“The project is unique in the way that two Historically Black Universities that focus on baccalaureate degree production collaborated with a research university to develop, implement and study a model of STEM graduate education and professional development,” Russell said. “Our findings provide information that will help educators, administrators and policymakers, as well as the general public.”

Russell and her colleagues released some of their findings in an article, titled “Promoting Pathways to STEM Careers for Traditionally Underrepresented Graduate Students,” in the Negro Educational Review.

“The systemic and pervasive underrepresentation of some ethnic and cultural groups in the STEM workforce has been a much-discussed topic for a while now,” Russell said. “It has been my main research focus for many years. Identifying factors that promote STEM persistence and graduate school completion can help diversify the STEM workforce in industry and higher education.”

Findings from the team’s research indicated that undergraduate research experiences, graduate education experiences, financial and institutional support, faculty/mentor and advisor support and intrinsic motivation influenced the study participants’ persistence in STEM undergraduate and graduate programs.

Many of the students who discussed their undergraduate STEM experiences described how they were motivated to pursue graduate studies based on experiences in a laboratory setting through various programs and projects while completing their undergraduate program.

Some participants discussed the importance of their institution fostering mentoring relationships, more social support networks and providing spaces that promote a sense of community and belonging.

Another key factor in graduate persistence was the influence of major professors and advisors relative to career aspirations and the overall graduate experience for the participants. These findings were well supported by existing literature that also described the critical role major professors play in helping their graduate students navigate the academy and influence their career decisions after graduate studies.

Specifically, participants in the research study described the importance of positive and meaningful interactions with their major professors. However, for students who did not feel supported by their major professors, there was a deterrent effect in their aspirations to pursue faculty positions and careers in the academy. There is some research that addresses the importance of having a major professor that helps students find their “scientific feet,” as well as characteristics of the “ideal” professor.

Some participants described the drawbacks of having a professor who was “hands off.” These students often felt they were on their own with little support to help them navigate graduate studies. Mentoring relationships (particularly between major professors and their graduate students) are critical and often a key determinant for the productivity and scholarship of graduate students. This is worth noting since retention of traditionally underrepresented groups is an important part of broadening participation and diversifying the STEM workforce.

Some students described an internal desire to persist in their programs. Many seemed to possess intrinsic motivation and “grit” which played a significant role in their persistence despite the barriers they encountered in their graduate programs.

Overall, the AGEP project highlighted several variables that could lead to increased student motivation to continue their graduate education. All the students described the faculty advisor as playing a significant role in supporting their graduate studies and encouraging their persistence. This can be a “make or break” relationship for graduate students’ career aspirations. Institutional support for graduate students increases student engagement and reduces the likelihood that students will drop out of the pipeline, and instead continue their pursuit of a career as a STEM professional, either in academia or industry. This is critical for diversifying the STEM workforce both in higher education and industry.

“Based on our research, more access to professional development programs for graduate students that provide knowledge on strategies for successfully navigating graduate school is important,” Russell said. “Furthermore, it is important to provide professional development for faculty and administrators to change policies and procedures that are barriers to persistence for traditionally underrepresented students. Institutional factors, increasing support and providing more opportunities to conduct research and publish at the undergraduate and graduate levels are all critical aspects of a graduate experience that prepares the student for success in academia or industry.”

Conclusions from this research can inform administrators and faculty in higher education of strategies that facilitate and support the career development of traditionally underrepresented students in pursuit of STEM degrees and will help diversify the workforce.