Viral contamination of acrylic resin removable denture bases in patients with COVID-19: A cross-sectional study.

STATEMENT OF PROBLEM: Salivary gland ducts are one of the primary targets of severe acute respiratory syndrome coronavirus 2. Moreover, saliva contains minor and major salivary gland secretions and a combination of nasopharyngeal and lung secretions. The acrylic resin bases of complete or partial removable dentures have pores and provide a favorable environment for the growth of microorganisms. PURPOSE: The purpose of this cross-sectional study was to investigate the presence of viral contamination of acrylic resin removable denture bases in patients with coronavirus disease 2019 (COVID-19). MATERIAL AND METHODS: The acrylic resin denture bases (partial and complete) of 29 patients with COVID-19 who underwent treatment in the Infectious Diseases Department of Razi Hospital in Ghaemshahr, Mazandaran, Iran, were evaluated. Samples were collected from the intaglio surface of the prostheses by direct swabbing and coding and were evaluated in a laboratory for the presence or absence of coronavirus. The relationship between hospital polymerase chain reaction (PCR) and denture PCR and the relationship between denture type and denture PCR were evaluated with the Fisher exact test (α=.05). RESULTS: Twenty-nine patients, age range 55 to 85 years, 18 women, 3 with partial dentures and 26 with complete dentures, were evaluated. The hospital PCR test was positive in 28 patients, while the denture PCR test was positive in 4 patients. No significant relationship was observed between the results of hospital PCR and denture PCR in patients with COVID-19 (P=.138). All 4 patients who tested positive for denture PCR had complete dentures. No significant relationship was found between denture type and denture PCR test results in patients with COVID-19 (P>999). CONCLUSIONS: Despite the microporous structure of the acrylic resin base, no statistically significant viral contamination was observed.

Comparison of azithromycin vs doxycycline prophylaxis in leptospirosis, A randomized double blind placebo-controlled trial.

INTRODUCTION: Leptospirosis is an important zoonotic disease in paddy field with 29.5% prevalence rate in Mazandaran province and 4% to 52% mortality rate among hospitalized patients. Prevention is an important strategy for the control of this disease. This study aimed to compare the prophylactic effect of azithromycin versus doxycycline against leptospirosis in an endemic area in north of Iran. METHODOLOGY: In this randomized double-blind placebo-controlled trial, paddy field workers (n = 187) were randomized to receive azithromycin (500mg weekly), doxycycline (200 mg weekly) or placebo starting one week before exposure to paddy field, during and to four weeks after. Paddy field workers aged 18- 65 years who signed the informed consent form were assessed for signs and symptoms of leptospirosis in addition to serologic evidence of the disease 6th and 12th week. Data were analyzed with SPSS version 13 using Chi-square and Fisher exact test and ANOVA. RESULTS: From June to September 2016, 187 participants were entered the study to receive azithromycin (n = 66), doxycycline (n = 71) or placebo (n = 50). In terms of preventing against clinical leptospirosis, there was not any significant difference between three arms, though there was statistically significant difference of seropositivity after 6 and 12 weeks in comparison to baseline among all three groups (P = 0.029) and between active treatment (eg. azithromycin and doxycycline) groups and placebo group (P = 0.01). CONCLUSION: Azithromycin like doxycycline decreased seropositivity without significant effect on clinical leptospirosis.