Are SARS-CoV-2 rapid antigen tests useful for the control of latest variants spreading?

Reverse Transcription Polymerase Chain Reaction (RT-PCR) conducted on nasopharyngeal swabs is the gold standard in the diagnosis of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). In Italy, recent guidelines indicate that rapid antigen tests (RATs) can be used for the isolation of positive patients or for the interruption of quarantine, but they are often less sensitive to detect positive subjects. Indeed, the performance of these RATs depends on the timing and the population on which they are evaluated. Herein, we evaluated the performance of BIOCREDIT COVID-19 Ag and Fluorecare® SARS-CoV-2 Spike Protein Test during a population screening in the Calabria Region, Southern Italy. We report that both antigen test shows low sensitivity in contrast to the high sensitivity declared by manufacturer (90% and 92%, respectively) and that the area under the curve (AUC) was good for Fluorecare® SARS-CoV- 2 Spike Protein Test but very poor for BIOCREDIT COVID-19 Ag. We suggest that these RATs should be re-evaluated in the current pandemic era.

From by-product to functional food: the survival of L. casei shirota, L. casei immunitas and L. acidophilus johnsonii, during spray drying in orange juice using a maltodextrin/pectin mixture as carrier.

The study reports the production of an innovative functional orange powder supplemented with probiotics and prebiotics, by implementing new ecofriendly and sustainable technologies, such as spray drying. The survival of Lactobacillus casei shirota, Lactobacillus casei immunitas and Lactobacillus acidophilus johnsonii, during spray drying in orange juice was proven and the stability of the powder obtained at room temperature and at 4 °C was investigated. Furthermore, the study highlighted the possibility to enhance the pectin obtained from the food agroindustry as a carrier for the spray-drying process. Combining maltodextrins and pectins at a 10:1 weight ratio. The study showed the efficiency of the maltodextrin/pectin mixture as carriers for the spray-drying process and the viability of the tested microorganisms during both the storage at room temperature and at 4 °C, showing that the latter represents the best storing condition for a longer viability of the microorganisms.