Shannon Reagan researches large-scale disinfection of public spaces for Senior Study

Shannon Reagan researches large-scale disinfection of public spaces for Senior Study

April 20, 2020

Shannon Reagan ’20 began researching surface disinfection of public spaces seven months ago – long before the COVID-19 outbreak. But her research – and the importance of effective large-scale surface disinfection – is now more timely than ever.

“I started this project in September 2019, so the novel coronavirus was definitely not on anyone’s radar,” said Reagan, a biology major from Tullahoma, Tenn. “While I have always thought that effective disinfection of public spaces such as classrooms and gyms is important, I never would have thought that a situation such as the one we are currently in would arise in the near future, much less before I had completely wrapped up this study.”

Her Senior Study compares the efficacy of two commercial electrostatic sprayer systems used for disinfecting public spaces. She came up with the idea with help from her academic advisor, Dr. Jennifer Brigati. Brigati, associate professor of biology, saw a newspaper article about a local school that purchased an electrostatic sprayer system for disinfecting classrooms, and she wondered if there was any peer-reviewed literature indicating that the sprayer systems were effective. 

“These sprayers are marketed as a way to decrease absenteeism in schools by decreasing the presence of viruses and bacteria on surfaces,” Brigati said. “They have the advantage of being able to spray chemicals over a large area very quickly when compared to typical spray bottles of disinfectant. However, I discovered that there was not any published research on the efficacy of the sprayers for disinfection of surfaces.”

Brigati received a grant to purchase a sprayer, hoping she could find a student who would be willing to test it. Around that time, Reagan approached Brigati about serving as her Senior Study advisor. Reagan, who was previously unaware of this relatively new disinfection method, jumped at the opportunity to pursue the project.

“Shannon is a diligent and conscientious student, so I knew she could tackle a challenging project and produce reliable data,” Brigati said.

In addition to the sprayer Brigati purchased, a representative from one of the College’s vendors, Kelsan, was able to loan Reagan a second electrostatic sprayer system to test. Both sprayers – the Victory Innovations Company Electrostatic Sprayer and the Clorox Total 360® System Electrostatic Sprayer – are designed to be loaded with chemical disinfectants, such as those made by Clorox or Bright Solutions. In order to test the efficacy of each electrostatic sprayer, Reagan used three relatively common strains of bacteria to inoculate three surfaces commonly touched in public settings, such as schools: polyester-based cloth, aluminum foil (to mimic all nonporous metal surfaces) and wood.

“The electrostatic sprayers work by atomizing particles of chemical disinfectants and putting a positive charge on them,” Reagan explained. “Because most surfaces and objects are negatively charged or neutral, it causes the particles of chemical disinfectant to adhere to the material and kill pathogens (microorganisms that cause illness in humans).” 

Relevant Research

Reagan found that both systems worked fairly well to disinfect the different types of surfaces, but one of the systems that she tested – the Clorox Total 360® System Electrostatic Sprayer with the Clorox Commercial Solutions Clorox Total 360® Disinfectant Cleaner – is FDA approved for inactivation of coronaviruses, “so Shannon’s thesis supports this as an effective method of disinfecting surfaces during the COVID-19 outbreak,” Brigati said.

 “It makes me feel like my research efforts are definitely important, and this type of research is relevant and should be continued,” Reagan said. “This is especially true because there is a paucity of peer-reviewed research on the use of electrostatic sprayers for disinfection. The results of my research support that there is monumental potential for this method of disinfection in public spaces, notably because it is able to disinfect areas in small cracks or crevices that would otherwise be missed via aerosol sprays or manual cleaning. I think testing this technology in airplanes and airports would be really interesting, especially because travel was a major source of how the coronavirus spread globally.”

Brigati, whose research background is in counter-bioterrorism (specifically the detection of pathogenic bacteria such as anthrax spores), said there are similarities between biological terrorism and a pandemic such as COVID-19.

“The anthrax attacks of 2001 occurred while I was in graduate school, and it provided a unique opportunity to jump into a very timely research project,” Brigati said. “While my specialty is man-made biological threats, there are many similarities between biological terrorism and naturally occurring pandemics. One thing that can be done when facing either type of threat is to look at relevant research, such as Shannon’s, and apply what was learned to the new problem.

“Shannon’s project was planned out and started before we knew SARS-CoV-2 (the virus that causes COVID-19) existed, but obviously there is great need for quick methods of surface disinfection now,” Brigati added. “SARS-CoV-2 is an enveloped virus, and thankfully it is even easier to inactivate than most bacteria, so Shannon’s research is definitely applicable to the current situation.”

A Learning Experience

Reagan said her Senior Study helped her gain more appreciation for the time and effort required to plan and execute lab research, and she was able to further refine her time management skills and “learn what it really means to be flexible and ‘adapt to survive,’” she said.

“Just because you plan something does not necessarily mean that it is going to work,” Reagan said. “I think the most difficult part of this research was finding a way to standardize each trial of the study, so I could start with the same concentration of bacterial CFUs (colony-forming units) each time. Once that was ironed out, the process went along a lot more smoothly.”

She expressed her appreciation for several Maryville College faculty and staff members who helped her with her Senior Study: Brigati, who provided encouragement, support and guidance throughout the process; Dr. Jeff Bay, chair of MC’s Division of Mathematics & Computer Science and professor of statistics, for helping her conduct and interpret the statistical analyses of her data; and Reggie Dailey, director of the Maryville College Physical Plant, for donating chemical disinfectants and target surfaces for the project. 

“I could not have completed the project without the help of these individuals, and I want to extend a huge token of appreciation and gratitude,” she said.

Reagan, who is graduating in May, has been accepted to the Physician Assistant (PA) program at Trevecca Nazarene University in Nashville, Tenn. She will start the 27-month program at the end of May and will be awarded a Master of Science in Medicine (M.S.M) degree when she completes the program in August 2022.

“I have wanted to be a PA since high school, and I am extremely thankful that I have been given the opportunity to attend PA school immediately following graduation,” Reagan said. “When I was thinking about potential Senior Study topics, I knew that I definitely wanted to do a microbiology project that would somehow relate to public health. After completing this research, I can confidently say that I know I have an aptitude for studying topics related to public health and medicine, so I am very confident in the career path that I have chosen.”

Reagan, a standout on the MC women’s soccer team, is the first Scots student-athlete to earn an NCAA Postgraduate Scholarship. She is one of just 126 student-athletes nationwide to receive the $10,000 award, which she will apply to her graduate studies. Each sports season (fall, winter and spring), 21 scholarships are available for men and 21 for women for use in an accredited graduate program. Last year, she was named the 2019 CoSIDA Academic All-America Division III Team Member of the Year as the top D-III women’s soccer player both on the field and in the classroom.

Brigati said she is “not at all surprised” that Reagan has produced an excellent Senior Study.

“Shannon works hard in the classroom, and has excelled at literally everything she has done at Maryville College,” Brigati said. “I am also very impressed with her ability to maintain balance in her life, as she put in just as much effort on the soccer field as she did in the classroom. She will start PA school this summer, and I am proud that we will be able to call Shannon Reagan an alumna of Maryville College.”

Video: Shannon Reagan ’20 tests the Victory Innovations Company electrostatic sprayer in one of Maryville College’s labs.

Story written by Chloe Kennedy, Assistant Director of Communications


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