COVID-19 infections are on the rise across all 50 U.S. states, marking an unexpected summer surge, according to the Centers for Disease Control and Prevention (CDC). As of August 12, 2026, the agency estimated that cases were growing or likely growing in every state.
While COVID-19 is often associated with winter months, health experts are observing increasing infection rates despite the warm weather, particularly in southern and western regions, with California and Texas reporting significant spikes. This trend follows a similar pattern observed last August, leading some experts to believe COVID-19 may be settling into a seasonal cycle. Dr. Susan Kline, a professor at the University of Minnesota, noted that rates typically hit their lowest in late June or early July, with an increase beginning in August, and a potential peak in late August or early September, a pattern that may be replicated this year.
The dominant variant circulating is XFG.1.1, which accounted for 22 to 40 percent of cases in July. While this variant is considered more contagious, it does not appear to cause more severe illness than previous strains. Despite the increase in cases, the weekly percentage of emergency department visits attributed to COVID-19 remains low at 0.3 percent, and overall national respiratory illness levels are also down.
Wastewater surveillance data, which helps track infections as fewer people test at home, indicates "very low" national COVID activity as of August 8. However, data from Stanford University's WastewaterSCAN program shows "high" COVID activity in wastewater across the U.S. with an "upward trend" over the preceding three weeks.
Health experts suggest the current wave of infections may be less severe than in previous years. Common symptoms in 2026 include cough, sore throat, congestion, fever, shortness of breath, headache, nausea, vomiting, diarrhea, and fatigue. These symptoms can appear two to 14 days after exposure and may start mild before progressing.
The CDC recommends staying up-to-date with COVID-19 vaccinations for individuals six months and older as a reliable method of protection. However, data from October 2025 indicates an increase in the number of people who say they will likely or definitely not get vaccinated.
Individuals at higher risk for severe illness include adults 65 and older, those with weakened immune systems, and the unvaccinated. Antiviral medications are available to reduce the severity and duration of symptoms if taken early. The CDC advises individuals to stay home and isolate until symptoms improve and they have been fever-free for at least 24 hours without medication.