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Understanding the impact of the new COVID-19 variant LB.1


The emergence of the COVID-19 variant LB.1 has raised concerns as it contributes to the ongoing summer wave of infections. Identified as a descendant of the JN.1 variant, LB.1 is now among the most prevalent variants in the United States, according to the Centers for Disease Control and Prevention (CDC).

Characteristics of LB.1

LB.1, part of the FLiRT lineage of COVID-19 variants, exhibits unique mutations, including a deletion in the spike protein. This mutation may enhance the variant’s ability to evade the immune response previously bolstered by vaccinations or past infections. Infectious disease experts, including Dr. Thomas Russo and Dr. Amesh Adalja, highlight the potential for increased transmissibility and immune evasion presented by LB.1.

Current impact and symptoms

Despite its growing prevalence, the symptoms associated with LB.1 remain consistent with those observed in other COVID-19 variants. Common symptoms include fever, cough, and fatigue, among others. However, there is ongoing discussion in the medical community regarding any unique symptoms specifically attributed to LB.1.

Vaccine efficacy against LB.1

The effectiveness of existing COVID-19 vaccines in preventing LB.1 infection appears to vary. While current vaccines may not prevent infection entirely, they are crucial in reducing the severity of the disease and preventing hospitalizations. Health experts continue to recommend vaccination as a key defense against severe outcomes.

Preventive measures

Standard COVID-19 preventive measures remain effective against LB.1. High-risk individuals are advised to stay up-to-date with vaccinations and consider additional precautions, such as wearing masks in crowded indoor settings. The ongoing development of vaccines targeting the FLiRT variants, including LB.1, is expected to enhance protection further.

As the situation evolves, continuous monitoring and adaptation of strategies will be essential in managing the impact of LB.1 and other emerging variants.