Here are the latest national COVID-19 trends, according to the U.S. Centers for Disease Control and Prevention (CDC) and major wastewater surveillance providers:
- SARS-CoV-2 concentration in wastewater increased 10% between September 2 and September 9, and the national wastewater trend is “high” (high concentration and no trend), per WastewaterSCAN.
- SARS-CoV-2 concentration in wastewater increased 2% between September 5 and September 12, and the national wastewater viral activity level is “low,” per the CDC.
- COVID-19 test positivity decreased 10%, from 5.5% of COVID-19 tests returning positive results during the week ending September 5 to 5.0% positive during the week ending September 12.
While national averages for COVID-19 metrics appear to be at a peak or plateau as of mid-September, the picture actually looks pretty different from region to region. COVID-19 spread seems to have peaked for the summer in the South, but may still be increasing in the West and is starting to go up more in Northern states.
In the South, wastewater and healthcare system data both indicate decreasing COVID-19 cases. The CDC’s infectious disease forecasting center estimates cases are “declining or likely declining” in 13 states as of September 16, including states across the South. Some parts of the region still have high disease levels, though: the CDC labels Texas’ wastewater viral activity levels as “very high,” which is especially concerning considering how high the agency’s baseline is for this metric.
The CDC has also finally changed its national wastewater viral activity level for COVID-19 to “low” from “very low,” both for its most recent data (the week ending September 12) and updating its national average from the prior week (ending September 5). See my video from last month for more context on why the CDC labels COVID-19 wastewater levels as “low” when we are clearly in a wave.
In the West, there are conflicting data on whether the wave has peaked or is still rising. The CDC’s regional average for the West reports a decline, while WWSCAN reports a plateau or slower increase and Biobot Analytics reports a significant increase. Test positivity data report a plateau in the Southwest (health region 9) and increase in the Northwest (region 10). Regardless of the direction, COVID-19 levels remain higher across this region.
The Northeast, and to a lesser extent the Midwest, are starting to report increasing COVID-19 spread after lower levels throughout the summer. SARS-CoV-2 levels in wastewater, test positivity, and emergency department visits are trending up in these regions. The CDC’s forecasting center estimates cases are “growing or likely growing” in 27 states, with most of those in the Northeast, Midwest, and Northwest.
Wastewater surveillance expert Marc Johnson shared on social media yesterday that SARS-CoV-2 was among the “most elevated viruses” in recent samples at the 44 testing sites in the network he runs, for the first time since winter 2025-26. The enterovirus D68 and rhinoviruses, which cause cold symptoms, are also elevated right now, he wrote.
As updated COVID-19 vaccines have started to become available, some health experts are raising concerns about their status in the CDC’s Vaccines for Children program, which provides free vaccinations to children who are uninsured, underinsured, or otherwise need financial support. The agency hasn’t yet decided whether COVID-19 vaccines will be part of the program this year, the Wall Street Journal reported last week. Delaying or restricting COVID-19 vaccines from this program could lead to increased severe infections and Long COVID among children.
