A recent study published in the Journal of Dental Research marks the first COVID-19 testing survey of asymptomatic patients in a dental setting. In their paper titled, “SARS-CoV-2 Positivity in Asymptomatic-Screened Dental Patients,” Conway et al. highlight the potential for dental offices to be viable and powerful locations for public health surveillance.
The study took place in Scotland over the course of 13 weeks — from August 3, 2020, to October 31, 2020 — and included 4,032 patients who were considered largely representative of the population. Of those participants, 22 (0.5%) tested positive for COVID-19. Over the course of the study, the positivity rate increased in tandem with the increase in prevalence of COVID-19 in the communities of the 31 dental settings.
These results are interesting because the significance of asymptomatic carriage and transmission remains poorly understood, despite being a notable characteristic of COVID-19. Other studies have reported wide differences in asymptomatic infection. Notice the discrepancy in the following findings:
- A small hospital study in China from the early stages of the pandemic found a 5% positivity rate in asymptomatic patients (Tian et al. 2020).
- A cruise ship in Japan in February 2020 found an asymptomatic positivity rate of 17.9% (Mizumoto et al. 2020).
- A village-wide study in Italy during the first-wave lockdown found a 42.5% asymptomatic positivity rate (Lavezzo et al. 2020).
Various systematic reviews also had varying results and identified limitations, such as the selection of study participants. However, a large household population-based study in Scotland found similar results to Conway et al. and was conducted around the same time in 2020.
This current study was not the first to take place in dental settings. Previously in Scotland, testing for human papillomavirus (HPV) was performed in dental practices because participants would be representative of the population.
Conway et al. identified dental offices as a good location for the research for several reasons. For one, dentists already have access to and make use of appropriate personal protective equipment (PPE). At a time when PPE was somewhat limited, it was beneficial that the study did not require obtaining more PPE to equip the researchers or clinicians.
Dental professionals can also reliably and safely screen patients for COVID-19 symptoms. Participants in the study were screened by a clinician upon arrival at an appointment, and those who displayed positive symptoms were excluded. Additionally, the dental teams were trained to perform a combined oropharyngeal and nasal swab test for COVID-19 in accordance with infection control protocol and while wearing proper PPE.
Aside from the important implications for the future study of COVID-19, this study may also have a lasting effect on the identification of dental settings as good locations for public health surveillance research. Dental professionals are already clinically trained and equipped and work regularly with the regional population.
As the researchers fittingly point out in their discussion, “Our data suggest that dental settings are a valuable location for public health surveillance.”