ABSTRACT
The aim of this study was to assess whether toothbrushing with a dentifrice containing an antimicrobial phthalocyanine derivative (APD) can reduce the intraoral viral load of SARS-CoV-2. Twenty COVID-19-positive dentate patients aged ≥18 years were selected instructed to brush their teeth for 2 min with a dentifrice containing APD. Self-collected samples of unstimulated saliva were carried out three times: T0 (baseline), T5 (5 min after toothbrushing), and T30 (30 min after toothbrushing). The analysis of viral RNA was performed by RT-qPCR for detection of three viral genes (ORF1ab, N and S genes). Results were statistically tested using Friedman's test and pairwise comparison with Bonferroni corrections, with a significance level of 5%. There was an increase in the cycle threshold (Ct) value from T0 to T5 in 13 patients (72.2%), and from T0 to T30 in 14 patients (77.8%). In two patients (11.1%) no SARS-CoV-2 was detected at T5 and five patients (27.8%) at T30. The Ct values were statistically significantly higher (p=0.020) at T30 in comparison to T0 and T5. This pilot study suggests that toothbrushing with a dentifrice containing APD could reduce the SARS-CoV-2 viral load in the oral cavity. However, further studies are needed to confirm this possible beneficial effect against SARS-CoV-2.
ABSTRACT
In coronavirus disease (COVID-19), the nucleotide-binding domain, leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) inflammasome is activated in response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Acute infections are accompanied by a sickness symptom complex (SSC) which is highly conserved and protects against infections and hyperinflammation. The aim of this study is to delineate the associations of COVID-19, SSC and NLPR3 rs10157379 T > C and NLPR3 rs10754558 C > G variants; and the protective role of SSC in SARS-CoV-2 infection. We recruited COVID-19 patients, 308 with critical, 63 with moderate and 157 with mild disease. Increased SSC protects against SARS, critical disease, and death due to COVID-19. Increasing age, male sex and rs10754558 CG significantly reduce SSC protection. The rs10157379 CT and rs10754558 GG genotypes are positively associated with SARS. Partial Least Squares analysis shows that a) 41.8% of the variance in critical COVID-19 symptoms is explained by SSC and oxygen saturation (inversely associated), inflammation, chest computed tomography abnormalities, increased body mass index, SARS and age (positively associated); and b) the effects of the NLRP3 rs10157379 and rs10754558 variants on critical COVID-19 are mediated via SSC (protective) and SARS (detrimental). SSC includes anosmia and dysgeusia, and maybe gastrointestinal symptoms. In conclusion, intersections among the rs10754558 variant, age, and sex increase risk towards critical COVID-19 by attenuating SSC. NLRP3 variants play an important role in SARS, and severe and critical COVID-19 especially in elderly male individuals with reduced SSC and with increased BMI, hypertension, and diabetes type 2.
