The NB.1.8.1 variant of SARS-CoV-2, the virus responsible for COVID-19, has been detected among international travelers arriving in the United States, including at airports such as Los Angeles International Airport. This variant has contributed to rising COVID-19 cases in regions such as China, Hong Kong, and Taiwan, prompting increased emergency room visits and hospitalizations in these areas.
Currently, the dominant variant in the U.S. is LP.8.1, which emerged in late 2024 and has been prevalent throughout the winter. In contrast, the NB.1.8.1 variant is gaining traction and has been reported to make up approximately 5% to 30% of sequenced samples in various countries. Another variant, XFG, appears to be spreading rapidly in North America and Europe, indicating a potential competitive dynamic between XFG and NB.1.8.1.
While NB.1.8.1 has not yet demonstrated a higher severity of illness compared to previous variants, its rapid spread has led to precautionary measures, including mask recommendations in Hong Kong and vaccine stockpiling in Taiwan. In the U.S., the Centers for Disease Control and Prevention (CDC) has detected cases of NB.1.8.1, with reports of its presence in various states.
Despite the emergence of this variant, the U.S. lacks a comprehensive surveillance system for SARS-CoV-2. This has raised concerns regarding the ability to effectively monitor and respond to new variants. Current vaccines may offer some protection against NB.1.8.1, but updated formulations targeting more recent variants like LP.8.1 might provide better immunity. As the situation evolves, the federal response remains uncertain, with ongoing discussions about vaccine approvals and public health strategy in the context of COVID-19.