National COVID-19 trends, September 10

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:

• About 4.1 in every 100,000 people were hospitalized for COVID-19 during the week ending August 24. (Note that these are provisional data.)
• COVID-19 test positivity has decreased 2%, from 16.7% of COVID-19 tests returning positive results during the week ending August 24 to 16.3% of tests during the week ending August 31.
• SARS-CoV-2 concentration in wastewater has decreased 7% between the week ending August 24 and the week ending August 31, and the national wastewater viral activity level is “high,” per the CDC.
• SARS-CoV-2 concentration in wastewater has decreased 10% between August 21 and August 28, per WastewaterSCAN.

The U.S.’s summer COVID-19 surge continues to slowly wane. While wastewater and healthcare system data have reported declines over the last couple of weeks, disease levels remain high across the U.S. — though you might not know it from looking at the CDC’s viral activity levels map, recently updated to an even more minimizing color scheme. Health officials are also on alert following a recent avian flu case.

Wastewater data from the CDC and WastewaterSCAN report that SARS-CoV-2 activity continues to decrease in the West and South, while increasing or at a plateau in the Northeast and Midwest. These regional differences average out into a plateau at the national level; the CDC’s estimate of national wastewater viral activity has stayed fairly consistent for all of August.

Notably, Biobot Analytics has yet to provide a national wastewater data update since mid-August. It’s unclear at this time whether the company is ending these updates, pausing them, shifting to a new schedule, or something else; they haven’t shared any public statements or responded to social media comments asking for updates. I’ve reached out to their team to ask about this and will report any response I receive in a future trends update article.

Healthcare system data present a similar picture to the available wastewater data: national hospitalizations, emergency department (ED) visits, and test positivity have gone down slightly in recent weeks, but are still close to their summer peaks. ED visits are particularly high for children under age 12, according to the CDC, thanks to school recently starting for this vulnerable and under-vaccinated age group. In the last week of August, the share of ED visits with diagnosed COVID-19 was higher for young children than for seniors over age 75.

It might be tough to recognize the current high COVID-19 spread across the U.S. if you’re looking at the CDC’s state-by-state wastewater activity map, recently updated to an even-less-threatening blue color scheme than its previous iteration. Since 2022, the agency has continually adjusted its COVID-19 maps to be less alarming, slowly progressing from bright reds and oranges to the current all-blue shades. The latest map at least clearly marks states that don’t have comprehensive wastewater data, but that’s the only compliment I can give it.

Despite this lack of alarm on the CDC’s dashboard, the agency reports that close to 1,000 Americans died of COVID-19 each week during the peak of this summer’s surge in mid-August. And these numbers are likely significant undercounts due to reporting delays, widespread lack of testing, and other issues in the death reporting system.

In other virus news: on Friday, the CDC and Missouri state health department reported a case of H5 avian flu in someone who hadn’t had known contact with infected animals. The case is cause for concern as the first not directly connected to dairy farms since H5N1 started spreading in cattle, though we don’t know enough yet to say this is evidence of person-to-person spread. 

As Helen Branswell writes in a recent article for STAT News, scientists have several unanswered questions about this case (such as why the individual was hospitalized) and how health officials are tracking it. The lack of transparency here parallels many issues with the U.S.’s continually failing COVID-19 response.