The Omicron variant wave: Where are we now and what are the prospects?

The Omicron variant BA.2 is the dominant form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in many countries, including those that have already implemented the strictest quarantine mandates that effectively contained the spread of the previous variants. Although many individuals were partially or fully vaccinated, confirmed Omicron infections have far surpassed all other variants combined in just a couple of months since the Omicron variant emerged. The ChAdOx1-S (AstraZeneca), BNT162b2 (Pfizer-BioNTech), and mRNA-1273 (Moderna) vaccines offer protection against the severe illness of SARS-CoV-2 infection; however, these currently available vaccines are less effective in terms of preventing Omicron infections. As a result, a booster dose of BNT162b2 or mRNA-1273 is recommended for individuals >12 years old who had received their second dose of the approved vaccines for >5 months. Herein, we review the studies that assessed the clinical benefits of the booster dose of vaccines against Omicron infections. We also analyzed public data to address whether early booster vaccination effectively prevented the surge of the Omicron infections. Finally, we discuss the consideration of a fourth dose of vaccine as a way to prevent possible upcoming infections.

New COVID-19 saliva-based test: How good is it compared with the current nasopharyngeal or throat swab test?

As of April 15, 2020, the US Food and Drug Administration has granted emergency use authorization to a first saliva test for diagnosis of severe acute respiratory syndrome coronavirus 2 infection, the device developed by RUCDR Infinite Biologics laboratory, Rutgers University. A key feature that distinguishes the saliva-based test from nasopharyngeal or oropharyngeal (throat) swabs is that this kit allows self-collection and can spare healthcare professionals to be at risk during collecting nasopharyngeal or oropharyngeal samples, thereby preserving personal protective equipment for use in patient care rather than sampling and testing. Consequently, broader testing than the current methods of nasal or throat swabs will significantly increase the number of people screening, leading to more effective control of the spread of COVID-19. Nonetheless, a comparison of saliva-based assay with current swab test is needed to understand what and how we can benefit from this newly developed assay. Therefore, in this mini-review article, we aimed to summarize the current and emerging tools, focusing on diagnostic power of different clinical sampling and specimens.