Background: SARS-Cov2 already has over than 215 million people and more than 4.5 million fatalities. The beginning of the pandemic condition has led the health authorities in several countries to adopt no-pharmacological preventive measures, such as schools closures. The return took place at a time when the country had the highest rates of infection and mortality. In particular because of the circulation of the gamma variant (P.1) and the vaccination program were beginning in the country. Therefore, we aimed to investigate the prevalence of SARS-CoV2 in daycares after the return of educational activities. Methods The study involved seven childcare facilities. Swab samples from the nasopharynx and region were collected from each participant. This study was carried out between March 16 and September 3, 2021. Viral RNA was extracted using Invitrogen’s RNA purification kit. Viral diagnosis was obtained using RT-PCR, through the TaqMan system. Viral detection was performed with Seegene panel, Allplex TM 2019-nCoV Assay kit. Results and Conclusion: The study population included 201 participants among daycare workers and children. Only one sample (0,5%) was tested positive for the presence of SARS-CoV-2, which was an asymptomatic childcare worker, and no secondary cases were detected. Considering that the return to day care activities occurred in a period with high number of cases of deaths and lack of vaccines throughout the country, it is believed that the several preventive measures used by the day care center could be an indication of effectiveness in preventing transmission of SARS-CoV2.

Introduction: The oral cavity is an important site for the entry and multiplication of respiratory viruses, and the immune system and oral microbiome act as antiviral barriers. Data regarding oral microbiome and COVID-19 is scarce. Therefore, a prospective cohort was conducted at the Hospital das Clínicas of FMUSP to evaluate the frequency of oral lesions associated with COVID-19 and the diversity of the oral microbiome on disease severity. Methods: Oral samples from SARS-CoV-2 positive patients were collected. After DNA extraction from the whole saliva samples, sequencing of the 16S rRNA gene using the Ion Torrent PGM platform was performed. Alpha and beta diversity analyses were conducted using the R program. Clinical data from electronic medical records were collected and multiple logistic regression model was constructed to assess the association between oral microbiome diversity and COVID-19 severity (oxygen therapy, mechanical ventilation). Results: The study included a total of 115 samples from 125 patients, 14 had oral lesions, the majority were female (54.8%), with a mean age of 55.4 years old. Around 59.1% of patients were in intensive care units(ICUs), 87.2% were using antibiotics, and 18.3% died. The most frequently antibiotics used were third-generation cephalosporins(35.7%), piperacillin/tazobactam(27%), and glycopeptides(21.7%). In general, the most abundant phyla were Firmicutes, Proteobacteria, and Bacteroidetes, representing 86.3% of the oral microbiome. Oral microbiome diversity analysis revealed statistical differences in COVID-19 severity (Shannon p=0.05), presence of oral lesions Shannon p=0.05), antibiotic use(Shannon p=0.04), and oxygen therapy Observed p=0.04). Differential abundance analysis identified specific taxa related to each variable, such as Prevotella in severe patients and Staphylococcus in individuals with oral lesions. Multivariable logistic regression pointed out that the SARS-CoV-2 PCR positive on the oral cavity and the age (above 60 years) were risk factors for disease severity. Conclusion: Despite the small number of participants with oral cavity lesions, we found significant differences in the microbial communities, particularly in the genus Staphylococcusd associated with oral lesions. Although the abundance of Prevotella was associated with severity of COVID-19 on the microbiome analysis, the multivariate model showed that only age and RT-PCR positive for SARS-CoV-2 on the oral cavity were independent risk factors for severity.

Objective Does the combined analysis of compounds in vaginal secretions plus vaginal microbiota composition improve the ability to predict risk for spontaneous preterm birth (SPTB) in women with a short cervix. Design Prospective observational study Setting Three hospitals in Brazil Samples Vaginal secretions from 568 women at 21-24 weeks gestation with cervical length measurement. Method Vaginal microbiome composition was determined by analysis of the V1-V3 region of the bacterial 16S ribosomal RNA gene. D- lactic acid and tissue inhibitor of matrix metalloproteinase (TIMP)-1 in vaginal secretions were measured by ELISA. Main outcome measures SPTB in relation to cervical length and dominant vaginal bacteria. Results When Lactobacillus crispatus was the dominant bacterium the concentration of TIMP-1 was lower, and D-lactic acid was higher, than when either L. iners or Gardnerella vaginalis predominated (p < 0.001). By ROC analysis, a D-lactic acid level < 0.7 mM, and a TIMP-1 level > 1.5 ng/ml best predicted the absence of L. crispatus dominance. Vaginal levels of TIMP-1 were highest (p = 0.024) and D-lactic acid levels were lowest (p=0.032) in women with the shortest cervical length. The absence of L. crispatus dominance increased the sensitivity for predicting a SPTB from 22.4% to 81.8% or 78.3% in women with a cervical length <25mm or <30mm, respectively. Conclusions Low vaginal D-lactic acid and high TIMP-1 indicates the loss of L. crispatus dominance and increased risk for SPTB in women with a short cervix.