This article is part of Harvard Medical School's continuing coverage of COVID-19.
At the height of the COVID-19 pandemic, many dental clinics faced temporary closure or capacity restrictions due to what was believed to be an increased risk associated with aerosol procedures.
Because dental procedures require clinicians to be in close proximity to their patient's mouth and nose, practicing dentistry was considered to be a high risk for transmission of SARS-CoV-2 infection.
A new paper published on Dec. 13 in JAMA Network Open reveals that clinical activities did not increase the risk of infection when performed in a clinical care setting with practitioners wearing standard personal protective equipment and participating in comprehensive SARS-CoV-2 surveillance testing.
The study was conducted at Harvard School of Dental Medicine, an academic clinical care setting, between August 2020 and February 2022. HSDM is the only graduate school at Harvard University that provides direct patient care within university-operated facilities.
As part of Harvard University's mandatory testing program, all on-site HSDM faculty, staff, and students participated in regular surveillance testing with a cadence that varied from one to three times per week depending on risk status. This program provided a pool of individuals in both clinical and nonclinical roles who were tested frequently for SARS-CoV-2.
"Our study found that the overall asymptomatic test positivity rate remained low, at 0.27 percent. Being involved in clinical activities did not increase the risk of COVID-19," said Sung Choi, HSDM instructor in oral health policy and epidemiology and an author of the study.
"While individuals involved in clinical activities performed a higher number of tests per week on average, test positivity rates remained lower than in nonclinical individuals, ensuring safety of both patients and practitioners in clinical settings," Choi said.
According to the study, the mean test positivity rate was 0.25 percent among individuals involved in patient-facing clinical activities compared with 0.36 percent among nonclinical individuals, revealing that faculty, students, and staff working in nonclinical roles contracted SARS-CoV-2 infections slightly more often than those in patient-facing roles.
"We were pleased that the comprehensive SARS-CoV-2 surveillance program at Harvard kept our community safe," said Giang Nguyen, associate provost for campus health and wellbeing, executive director of Harvard University Health Services, an HMS associate professor of medicine at Massachusetts General Hospital, and a contributor to the study.
"The work done at the dental school during the pandemic demonstrated that the school delivered clinical care in a safe manner, even in a setting with relatively high density of students, staff, and faculty on campus," Nguyen said.
The findings suggest that implementing an adaptive testing cadence based on individual risk status, can be an effective measure for institutions to use for timely detection of SARS-CoV-2 infection and to reduce the risk of infection within academic clinical care settings.
It may also provide a blueprint for how clinical care can be performed safely in academic settings when faced with future virus outbreaks.
"The results of this study underscore that a dental academic setting is safe for students, clinicians, and staff," said HSDM Dean William Giannobile. "Furthermore, the delivery of dental care to patients during the pandemic was safe with no documented transmission of SARS-CoV-2 from doctor to patient."