Clinical validation of automated and rapid mariPOC SARS-CoV-2 antigen test.

COVID-19 diagnostics was quickly ramped up worldwide early 2020 based on the detection of viral RNA. However, based on the scientific knowledge for pre-existing coronaviruses, it was expected that the SARS-CoV-2 RNA will be detected from symptomatic and at significant rates also from asymptomatic individuals due to persistence of non-infectious RNA. To increase the efficacy of diagnostics, surveillance, screening and pandemic control, rapid methods, such as antigen tests, are needed for decentralized testing and to assess infectiousness. A novel automated mariPOC SARS-CoV-2 test was developed for the detection of conserved structural viral nucleocapsid proteins. The test utilizes sophisticated optical laser technology for two-photon excitation and individual detection of immunoassay solid-phase particles. We validated the new method against qRT-PCR. Sensitivity of the test was 100.0% (13/13) directly from nasopharyngeal swab specimens and 84.4% (38/45) from swab specimens in undefined transport mediums. Specificity of the test was 100.0% (201/201). The test's limit of detection was 2.7 TCID50/test. It showed no cross-reactions. Our study shows that the new test can detect infectious individuals already in 20 min with clinical sensitivity close to qRT-PCR. The mariPOC is a versatile platform for syndromic testing and for high capacity infection control screening of infectious individuals.

Similarity of salivary microbiome in parents and adult children.

BACKGROUND: Human saliva contains approximately 700 bacterial species. It has been reported that the salivary microbiome of a large family of closely related individuals consisting of multiple households is similar but the relatedness of salivary bacteria between generations of parents and their children has not yet been investigated. The objectives were to investigate the entirety of salivary bacterial DNA profiles and whether and how families share these profiles and also compare these communities between grandparents and their first daughter generations (F1) using 16S rRNA gene amplicon sequencing. RESULTS: The most abundant phyla in two separate families were Firmicutes, Bacteroidetes, Proteobacteria, Fusobacteria and Actinobacteria. Family ties explained 13% of the variance between individuals' bacterial communities (R 2 = 0.13; P = 0.001). Mothers shared more OTUs with adult children compared to fathers, but this linkage seemed to be weaker in the nuclear family with older adult children. We identified 29 differentially abundant genus level OTUs (FDR < 0.05) between families, which accounted for 31% of the total identified genus level OTUs. CONCLUSIONS: Our results indicate that adult family members share bacterial communities and adult children were more similar to mothers than fathers. The observed similarity in oral microbiome between parent-child pairs seemed to weaken over time. We suggest that our analysis approach is suitable for relatedness study of multigenerational salivary bacteria microbiome.

Increased tooth brushing frequency is associated with reduced gingival pocket bacterial diversity in patients with intracranial aneurysms.

OBJECTIVES: The objective of this study was to investigate the association of tooth brushing frequency and bacterial communities of gingival crevicular fluid in patients subjected to preoperative dental examination prior to operative treatment for unruptured intracranial aneurysms. METHODS: Gingival crevicular fluid samples were taken from their deepest gingival pocket from a series of hospitalized neurosurgical patients undergoing preoperative dental screening (n = 60). The patients were asked whether they brushed their teeth two times a day, once a day, or less than every day. Total bacterial DNA was isolated and the V3-V4 region of the 16S rRNA gene was amplificated. Sequencing was performed with Illumina's 16S metagenomic sequencing library preparation protocol and data were analyzed with QIIME (1.9.1) and R statistical software (3.3.2). RESULTS: Bacterial diversity (Chao1 index) in the crevicular fluid reduced along with reported tooth brushing frequency (p = 0.0002; R2 = 34%; p (adjusted with age and sex) = 0.09; R2 = 11%) showing that patients who reported brushing their teeth twice a day had the lowest bacterial diversity. According to the differential abundant analysis between the tooth brushing groups, tooth brushing associated with two phyla of fusobacteria [p = 0.0001; p = 0.0007], and one bacteroidetes (p = 0.004) by reducing their amounts. CONCLUSIONS: Tooth brushing may reduce the gingival bacterial diversity and the abundance of periodontal bacteria maintaining oral health and preventing periodontitis, and thus it is highly recommended for neurosurgical patients.