Popular Science: “Over Labor Day weekend, pharmacies across the country began receiving shipments of new Omicron- specific mRNA booster shots against COVID-19, after the Centers for Disease Control and Prevention (CDC) and Food and Drug Administration (FDA) signed off on their use last week. The updated formulas, which will become the standard booster for almost everyone in the US, were developed by Pfizer/BioNtech and Moderna in the 10 months since Omicron first emerged. Although the boosters are almost identical to the original shots, they’re bivalent, which means they can induce an immune response to both the original strain of SARS-CoV-2, as well as the BA.4/BA.5 Omicron strains that currently cause about 90 percent of the country’s COVID cases…”