Asymptomatic carriers of COVID-19 in a confined adult community population in Quebec: A cross-sectional study.

Several countries have undertaken social distancing measures to stop SARS-CoV-2 spread. Asymptomatic carriers' prevalence is unknown and would provide essential information on hidden viral circulation. In our cross-sectional study, 1.82% of 330 asymptomatic confined individuals living in the community carried SARS-CoV-2 despite no contact with declared cases, raising concerns about unnoticed transmission.

SARS-CoV-2 detection by direct rRT-PCR without RNA extraction.

Rapid and reliable screening of SARS-CoV-2 is fundamental to assess viral spread and limit the pandemic we are facing. In this study, we compared direct rRT-PCR method (without RNA extraction) using SeeGene AllplexTM 2019-nCoV rRT-PCR with the RealStar® SARS-CoV-2 rRT-PCR kit (Altona Diagnostics). Furthermore, we assessed the impact of swab storage media composition on PCR efficiency. We show that SeeGene and Altona's assays provide similar efficiency. Importantly, we provide evidence that RNA extraction can be successfully bypassed when samples are stored in UTM medium or in molecular water but not when samples are stored in saline solution and in Hanks medium.

Chronic Larva Currens Following Tourist Travel to the Gambia and Southeast Asia Over 20 Years Ago.

Larva currens is the cutaneous manifestation of human infection with the geotropic helminth Strongyloides stercoralis. Strongyloidiasis is a lifelong infection unless treated. A high index of suspicion is needed to prevent chronic symptoms of strongyloidiasis (eg, larva currens, eosinophilia, abdominal discomfort) and to prevent fatal dissemination. We present a case of chronic larva currens following tourist travel to the Gambia and Southeast Asia>20 years ago. This case highlights several important features of larva currens and strongyloidiasis, including the chronicity of symptoms, the rapidity of the migratory serpiginous rash, and the absence of high-grade eosinophilia.

Performance of MycAssay Aspergillus DNA real-time PCR assay compared with the galactomannan detection assay for the diagnosis of invasive aspergillosis from serum samples.

Invasive aspergillosis (IA) is a major problem in the immunocompromised population, and its diagnosis is difficult due to the low sensitivity of available tests. Detection of Aspergillus nucleic acid by polymerase chain reaction (PCR) in serum samples is a promising diagnostic tool; however, use of multiple "in-house" methods precludes standardization. The first commercial PCR assay, MycAssay Aspergillus (Myconostica, Ltd), became available recently, and its performance in the diagnosis of IA was evaluated and compared with the galactomannan (GM) assay. Serum samples obtained from patients with hematological cancer were tested retrospectively with MycAssay Aspergillus PCR. Per-episode and per-test analyses were undertaken with 146 sera from 35 hematological patients. Sixteen patients had proven or probable IA and 19 had possible or no IA. In per-episode analysis, MycAssay Aspergillus had a sensitivity of 43.8% (95% confidence interval [CI], 19.8%-70.1%) and a specificity of 63.2% (95% CI, 38.4%-83.7%) for IA diagnosis. In per-test analyses, MycAssay Aspergillus had a lower specificity than the GM assay (83.3% vs. 93.1%, P = 0.04). The addition of PCR to routine clinical practice would have permitted the diagnosis of one additional probable IA in our cohort. Use of PCR instead of GM assay would have delayed the diagnosis in two cases. Aspergillus DNA detection by PCR with serum specimens using MycAssay showed a lower specificity than the GM assay and was associated with a low sensitivity for IA diagnosis. More studies are needed to determine the exact role of MycAssay in IA diagnosis in patients with hematological malignancy.

Universal vaginal applicator for the uniform distribution of vaginal gel and cream formulations: a magnetic resonance imaging study.

OBJECTIVE: Conventional vaginal applicators with a single apical hole do not distribute vaginal formulations homogenously and do not cover the entire vaginal and cervical mucosa. To overcome this problem and offer women further protection against vaginal infections, we designed a unique vaginal applicator with multiple apical and lateral holes. We have previously shown that the new applicator distributes an investigational vaginal gel homogenously over the entire vaginal and cervical mucosa. In this study, we investigated (using MRI) whether the new applicator works as well with marketed vaginal gels and creams. METHODS: Eighteen women participated in the study and six vaginal gels and creams were tested. Each woman used a marketed vaginal product with its own commercial applicator (CA) once and with our universal vaginal applicator (UVA) once to deliver the same product. The applications were separated by a one-week period. Pelvic MRI was performed immediately after vaginal application to evaluate the product's distribution and mucosal coverage. RESULTS: Immediately after application of the vaginal product, the UVA homogenously distributed the six products (3 gels and 3 creams) over the entire vaginal and cervical mucosa. On the other hand, the tested CA delivered four products (3 gels and 1 cream) mainly to the cervix and the upper vagina, but not to the mid and lower vagina; for the other two creams, the distribution was similar to that of UVA. Furthermore, the UVA received the highest acceptability score. CONCLUSION: The UVA can be used to deliver different vaginal gel and cream products homogenously throughout the vagina. This was the first time the UVA had been tested with marketed vaginal gels and creams. This applicator, giving uniform mucosal coverage and being highly acceptable, may help women to better protect themselves against sexually transmitted infections.

Objectif : Les applicateurs vaginaux conventionnels dotés d'un seul orifice apical ne permettent pas de distribuer les formulations vaginales de façon homogène et ne couvrent pas l'intégralité de la muqueuse vaginale et cervicale. Pour surmonter ce problème et offrir aux femmes davantage de protection contre les infections vaginales, nous avons conçu un applicateur vaginal unique en son genre doté de multiples orifices apicaux et latéraux. Nous avons déjà démontré que ce nouvel applicateur permettait de distribuer un gel vaginal expérimental de façon homogène sur l'intégralité de la muqueuse vaginale et cervicale. Dans le cadre de cette étude, nous nous sommes penchés (en ayant recours à l'IRM) sur la question de savoir si ce nouvel applicateur fonctionnait tout aussi bien dans le cas des crèmes et des gels vaginaux offerts sur le marché. Méthodes : Dix-huit femmes ont participé à l'étude et six crèmes et gels vaginaux ont été mis à l'essai. Chacune de ces femmes a utilisé à deux reprises un même produit vaginal offert sur le marché : une fois au moyen de l'applicateur commercial fourni par le fabricant (AC) et une autre fois au moyen de notre applicateur vaginal universel (AVU). Une période d'une semaine séparait ces deux applications. Une IRM pelvienne a été menée immédiatement à la suite de chacune de ces applications vaginales afin d'évaluer la distribution du produit et l'aire couverte en ce qui concerne la muqueuse. Résultats : Immédiatement à la suite de l'application du produit vaginal, nous avons constaté que l'utilisation de l'AVU permettait la distribution homogène des six produits (trois gels et trois crèmes) sur l'intégralité de la muqueuse vaginale et cervicale. En revanche, dans le cas de quatre des produits en question (trois gels et une crème), l'AC mis à l'essai a donné lieu à une distribution ayant principalement atteint le col utérin et la partie supérieure du vagin (excluant ainsi les parties intermédiaire et inférieure du vagin); pour ce qui est des deux autres crèmes, la distribution obtenue était semblable à celle qu'a permise l'AVU. De surcroît, l'AVU a obtenu le score d'acceptabilité le plus élevé. Conclusion : L'AVU peut être utilisé pour assurer l'administration de divers produits vaginaux en gel et en crème de façon homogène dans tout le vagin. Il s'agissait de la première mise à l'essai de l'AVU au moyen de crèmes et de gels vaginaux offerts sur le marché. Cet applicateur, qui permet de couvrir l'aire muqueuse de façon uniforme et qui compte une acceptabilité élevée, pourrait aider les femmes à mieux se protéger contre les infections transmissibles sexuellement.

Efficient production of HIV-1 virus-like particles from a mammalian expression vector requires the N-terminal capsid domain.

It is now well accepted that the structural protein Pr55(Gag) is sufficient by itself to produce HIV-1 virus-like particles (VLPs). This polyprotein precursor contains different domains including matrix, capsid, SP1, nucleocapsid, SP2 and p6. In the present study, we wanted to determine by mutagenesis which region(s) is essential to the production of VLPs when Pr55(Gag) is inserted in a mammalian expression vector, which allows studying the protein of interest in the absence of other viral proteins. To do so, we first studied a minimal Pr55(Gag) sequence called Gag min that was used previously. We found that Gag min fails to produce VLPs when expressed in an expression vector instead of within a molecular clone. This failure occurs early in the cell at the assembly of viral proteins. We then generated a series of deletion and substitution mutants, and examined their ability to produce VLPs by combining biochemical and microscopic approaches. We demonstrate that the matrix region is not necessary, but that the efficiency of VLP production depends strongly on the presence of its basic region. Moreover, the presence of the N-terminal domain of capsid is required for VLP production when Gag is expressed alone. These findings, combined with previous observations indicating that HIV-1 Pr55(Gag)-derived VLPs act as potent stimulators of innate and acquired immunity, make the use of this strategy worth considering for vaccine development.