US COVID Cases Surge Nationwide Amid New Variant, CDC Warns

The United States is experiencing a late summer surge in COVID-19 cases driven by the NB.1.8.1 variant, nicknamed Nimbus, which now accounts for over 40% of infections. The CDC reports increasing test positivity rates, particularly high in southern and western states, with some regions seeing rates as high as 17.9%. Emergency department visits and hospitalizations for COVID-19 are rising, especially in younger age groups, although deaths remain low. Health experts emphasize the importance of updated COVID-19 vaccinations, especially for high-risk populations, and recommend continued preventive measures such as mask-wearing and hand hygiene. The surge is partly attributed to waning immunity, increased travel, and seasonal behaviors like large gatherings around Labor Day. Wastewater surveillance confirms elevated viral activity in multiple states, underscoring the ongoing spread despite underreporting from at-home testing.