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Omicron sublineages

Omicron sublineages such as XBB.1.5 have reduced susceptibility to several monoclonal antibody products.

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Jan 19, 2026
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How do bivalent and variant-adapted COVID-19 boosters differ in formulation and immune response?

Bivalent COVID-19 boosters combine mRNA or protein from two spike variants—typically the ancestral (Wuhan-like) strain plus an Omicron sublineage—to broaden antibody recognition compared with original...

Jan 19, 2026
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New covid health advisory for 2026

A new COVID-19 vaccine formulation for the 2025–2026 season has received FDA approval, but as of the latest agency and institutional notices it does not yet carry a formal ACIP/CDC recommendation — le...