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 12% between October 21 and October 28, and the national wastewater trend is “high” (high concentration and upward trend), per WastewaterSCAN.
- SARS-CoV-2 concentration in wastewater decreased 17% between October 24 and October 31, and the national wastewater viral activity level is “moderate,” per the CDC.
- COVID-19 test positivity stayed consistent, with 3.5% of COVID-19 tests returning positive results during both weeks ending October 24 and October 31.
COVID-19 levels continue to be high for this time of year throughout much of the U.S., as the summer’s wave pushes further into the fall. Some areas in the West and South recently reported new increases after levels declined from their summer peaks, while parts of the Northeast and Midwest are experiencing outbreaks with the onset of colder weather. Flu season has already arrived, too.
This is a confusing time to look at national and even regional wastewater surveillance trends. There are a lot of differences among the three national data providers (the CDC, WastewaterSCAN, and Biobot) because they each have different geographical distributions of testing sites, timing lags, methods for analyzing and presenting data, and more. While I do my best in these updates to highlight notable hotspots, it’s always good to look for surveillance data in your specific location or nearby, if your city or county isn’t being tested.
In the West, we continue to see COVID-19 levels declining in California, Oregon, and Washington while they are increasing in states further inland, according to both wastewater and emergency department visits. Levels are still higher in this region than in other parts of the U.S., though; for instance, the CDC’s PCR testing network reports a test positivity rate of 5.6% for the Northwest states (health region 10) for the week ending October 31, which is far below the region’s summer peak of 10.7% but well above the latest national average of 3.5%.
The South also has diverging trends. Wastewater data from WWSCAN suggest potential COVID-19 increases in parts of Florida, Georgia, Alabama, Maryland, and Louisiana. Test positivity and ED data similarly suggest COVID-19 could be increasing again in some Southeast states (health regions 3 and 4) while it’s declining or at a plateau further west (health region 6).
The CDC’s forecasting center, which uses ED data for its modeling, estimates that COVID-19 cases are only “declining or likely declining” in four states as of November 5: California, Washington, Oregon, and Texas. Cases are “growing or likely growing” in 33 states, per the center, including states across the Northeast, Midwest, Southeast, and Mountain West.
Levels still haven’t definitively gone up yet across the Northeast and Midwest, which usually see bigger surges in the colder months. But a couple of Northeast states continue to be likely hotspots: Massachusetts and Connecticut have reported higher SARS-CoV-2 levels in wastewater throughout October, per the CDC’s wastewater surveillance data, and some testing sites across Maine, New Jersey, and Pennsylvania have also recently reported increases and/or higher levels.
Compared to COVID-19, the flu patterns are less ambiguous: flu cases are on the rise across the country, according to both wastewater and healthcare system data. In the week ending October 31, nearly 3% of doctor’s visits in the CDC’s flu surveillance network were for influenza-like illness (fever plus a cough or sore throat), getting close to the official threshold for flu season. This metric has already crossed 3% in the West and South, which saw an early start to the season.
Bird flu also continues to be a concern, as Washington state reported the first U.S. death from H5N1 in 2026 last week, along with two additional human cases. “Autumn is beginning to look more clearly like the start of bird-flu season for livestock, and, by extension, the time of year that the spillover risk to humans could be highest,” wrote science journalist Roxanne Khamsi in a recent article for The Atlantic.
