Summary (tl;dr)

The United States is currently experiencing a growing summer COVID-19 surge, with rising infections across all 50 states, primarily driven by new variants and waning immunity.

Essential Background

Unlike influenza and RSV, which typically follow predictable fall and winter patterns, SARS-CoV-2 has exhibited a more variable transmission pattern since 2020, including recurring spring and summer waves alongside winter peaks. These seasonal increases are influenced by factors such as regional climate differences, human behavior, waning population immunity, and the emergence of new variants. Historically, summer surges have been observed particularly in southern U.S. states before shifting northward in winter.

The Full Story

As of August 2026, a significant summer COVID-19 surge is underway across the United States, with health officials noting increases in infections across nearly all states. Data from wastewater surveillance programs like WastewaterSCAN and Biobot Analytics show rising concentrations of SARS-CoV-2 nationally, reaching "high" levels in some areas. While the surge is widespread, the most pronounced increases are reported in the Southern and Western regions of the country. This uptick is attributed to seasonal behavioral patterns, such as increased indoor gatherings in air-conditioned spaces to escape summer heat, holiday travel, and a decline in immunity from previous vaccinations or infections. The current wave is also influenced by the circulation of new Omicron descendant variants, including "Cicada" (BA.3.2), which contains over 70 mutations in its spike protein and has been detected in 29 U.S. states, and the "Nimbus" (NB.1.8.1) and "Stratus" (XFG) variants.

Why It Matters

Despite overall respiratory virus activity remaining low nationally, and the current wave generally appearing milder with fewer hospitalizations compared to earlier pandemic stages, COVID-19 still poses a risk. The virus can cause severe disease, lead to hospitalizations, and contribute to long COVID, especially for vulnerable populations such as older adults, infants, and immunocompromised individuals. Public health experts emphasize the importance of continued surveillance and recommend that high-risk individuals consider getting vaccinated with the current formulation, rather than waiting for updated vaccines expected later in the year, to bolster protection during this active transmission period. The consistent summer surges highlight COVID-19's evolving seasonal pattern, which now includes prominent warm-weather peaks in addition to winter activity.

Geographic Location

• United States (experiencing a nationwide summer COVID-19 surge)
• Southern United States (experiencing most pronounced increases in COVID-19 activity)
• Western United States (experiencing most pronounced increases in COVID-19 activity)
• Key Biscayne, Miami-Dade County, Florida, United States (notable rise in COVID-19 wastewater levels)
• St. Petersburg, Pinellas County, Florida, United States (notable rise in COVID-19 wastewater levels)
• The Woodlands, Montgomery County, Texas, United States (notable rise in COVID-19 wastewater levels)
• Palo Alto, Santa Clara County, California, United States (high and rising COVID-19 wastewater levels)
• Marin County, California, United States (high and rising COVID-19 wastewater levels)
• Sunnyvale, Santa Clara County, California, United States (high and rising COVID-19 wastewater levels)
• San Jose, Santa Clara County, California, United States (high and rising COVID-19 wastewater levels)
• San Francisco, San Francisco County, California, United States (experiencing highest COVID-19 levels since last September, with increasing hospitalizations and positive tests)