Search Results (3)

The international spread of HIV-1 sub-subtype A6 raises concerns due to its association with contraindications for long-acting injectable formulations of cabotegravir (LA-CAB) and rilpivirine (LA-RPV). This study investigated its increasing proportion in Belgium, assessing transmission dynamics and potential migration links. Additionally, genotypic drug resistance in the Belgian HIV-1 sub-subtype A6 population were analyzed and four automatic subtyping tools were compared. A dataset of 4764 HIV-1 protease and reverse transcriptase (RT) sequences from newly diagnosed, treatment-naïve individuals in Belgium (2013–2022) was analyzed. A combination of phylogenetic analysis and online subtyping tools identified 136 sub-subtype A6 sequences. The increase in the proportion of HIV-1 sub-subtype A6 observed in Belgium since 2020 reflects changing transmission patterns, especially among Belgium-born men having sex with men, and cannot be solely linked to the recent influx of Ukrainian migrants. Of these sub-subtype A6 sequences, less than 10% showed LA-CAB + LA-RPV resistance, mainly due to E138A within RT. HIVdb and ANRS reliably assessed resistance in this therapy-naïve cohort, and HIVdb, COMET, and SmartGene^® produced concordant subtyping results. While algorithm choice has little impact at low resistance prevalence, further research is necessary and HIVdb and ANRS remain more suitable for ongoing clinical and research use. Full article

Background/Objectives: 16S ribosomal RNA sequencing has, for several years, been the main means of identifying bacterial and archaeal species. Low-throughput Sanger sequencing is often used for the detection and identification of microbial species, but this technique has several limitations. The use of high-throughput sequencers may be a good alternative to improve patient identification, especially for polyclonal infections and management. Kraken 2 and KrakenUniq are free, high-throughput tools providing a very rapid and accurate classification for metagenomic analyses. However, Kraken 2 can present false-positive results relative to KrakenUniq, which can be limiting in hospital settings requiring high levels of accuracy. The aim of this study was to establish an alternative next-generation sequencing technique to replace Sanger sequencing and to confirm that KrakenUniq is an excellent analysis tool that does not present false results relative to Kraken 2. Methods: DNA was extracted from reference bacterial samples for Laboratory Quality Controls (QCMDs) and the V2-V3 and V3-V4 regions of the 16S ribosomal gene were amplified. Amplified products were sequenced with the Illumina 16S Metagenomic Sequencing protocol with minor modifications to adapt and sequence an Illumina 16S library with a small 500-cycle nano-flow cell. The raw files (Fastq) were analyzed on a commercial Smartgene platform for comparison with Kraken 2 and KrakenUniq results. KrakenUniq was used with a standard bacterial database and with the 16S-specific Silva138, RDP11.5, and Greengenes 13.5 databases. Results: Seven of the eight (87.5%) QCMDs were correctly sequenced and identified by Sanger sequencing. The remaining QCMD, QCMD6, could not be identified through Sanger sequencing. All QCMDs were correctly sequenced and identified by MiSeq with the commercial Smartgene analysis platform. QCMD6 contained two bacteria, Acinetobacter and Klebsiella. KrakenUniq identification results were identical to those of Smartgene, whereas Kraken 2 yielded 25% false-positive results. Conclusions: If Sanger identification fails, MiSeq with a small nano-flow cell is a very good alternative for the identification of bacterial species. KrakenUniq is a free, fast, and easy-to-use tool for identifying and classifying bacterial infections. Full article

Schools have been a point of attention during the pandemic, and their closure one of the mitigating measures taken. A better understanding of the dynamics of the transmission of SARS-CoV-2 in elementary education is essential to advise decisionmakers. We conducted an uncontrolled non-interventional prospective study in Belgian French-speaking schools to describe the role of attending asymptomatic children and school staff in the spread of COVID-19 and to estimate the transmission to others. Each participant from selected schools was tested for SARS-CoV-2 using a polymerase chain reaction (PCR) analysis on saliva sample, on a weekly basis, during six consecutive visits. In accordance with recommendations in force at the time, symptomatic individuals were excluded from school, but per the study protocol, being that participants were blinded to PCR results, asymptomatic participants were maintained at school. Among 11 selected schools, 932 pupils and 242 school staff were included between January and May 2021. Overall, 6449 saliva samples were collected, of which 44 came back positive. Most positive samples came from isolated cases. We observed that asymptomatic positive children remaining at school did not lead to increasing numbers of cases or clusters. However, we conducted our study during a period of low prevalence in Belgium. It would be interesting to conduct the same analysis during a high prevalence period. Full article