The prevalence of positive patients to COVID-19 rapid nasopharyngeal antigen testing in private dental practices.

Background: A quick diagnosis is crucial in effectively limiting the spread of SARS-CoV-2. The study aims to assess the prevalence of positive rapid tests in private dental practices.

Methods: This is an observational study. 532 COVID-19 rapid nasopharyngeal antigen tests were carried out in the Veneto region of Italy. Patients of 4 dental practices in different cities (Caorle, Montebelluna, Treviso and Vicenza) were screened with a rapid test (Rapid Test COVID-19 Ag immunochromatographic assay, Techno Genetics) throughout November and December 2020. All the positive results from rapid tests were further investigated with a molecular test (PCR). All the patients tested showed no symptoms associated with SARS-CoV-2 infection and had already undergone triage and temperature measurement. In total 532 tests were taken: 202 in Caorle (Venice), 130 in Montebelluna (Treviso), 100 in Treviso, and 100 in Vicenza. Statistical analysis was carried with the computing environment R version 3.2.1 (R Foundation for Statistical Computing, Vienna, Austria). In particular, R was used for estimating the P value of the χ test. The test was considered significant if the P value was lower or equal to 0.05.

Results: The prevalence of the rapid tests that resulted positive was 7.14% (38 out of 532 in total, 22 out of 202 in Caorle, 6 out of 130 in Montebelluna, 4 out of 100 in Treviso and 6 out of 100 in Vicenza). Among these patients, 36 tested positive also with a molecular test (94.74%), in particular, 21 in Caorle, 5 in Montebelluna, 4 in Treviso, and 6 in Vicenza.

Conclusions: The prevalence of positive patients screened with a rapid test in private dental practices stands at 7.14% and it was confirmed in most of the patients with molecular tests. Therefore, in high-risk environments like dental practices, it is imperative to follow all the precautionary measures, and having every patient tested with a rapid test could be taken into consideration to limit the spread of COVID-19 infection.