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 decreased 8% between October 14 and October 21, and the national wastewater trend is “high” (high concentration and downward trend), per WastewaterSCAN.
- SARS-CoV-2 concentration in wastewater increased 11% between October 17 and October 24, and the national wastewater viral activity level is “moderate,” per the CDC.
- COVID-19 test positivity decreased 9%, from 3.8% of COVID-19 tests returning positive results during the week ending October 17 to 3.5% positive during the week ending October 24.
Higher COVID-19 levels from the summer’s surge are still persisting through late October. Some regions where we thought the year’s biggest outbreaks were already done are now reporting renewed increases and high plateaus, showing how the SARS-CoV-2 virus remains unpredictable in this time of very limited public health measures to curb its spread.
Coronavirus levels in wastewater remain high across much of the South. The CDC reports “high” wastewater viral activity levels in Florida, South Carolina, Arkansas, and Maryland (though data are limited in the latter two states) and “moderate” levels in eight other Southern states. While the CDC’s statewide average for Florida declined this week to “high” from “very high,” some testing sites in the state report potential new increases, per WastewaterSCAN.
In the West, there’s a divergence between coastal states and those further inland. COVID-19 levels seem to be declining — though they are still high — in California, Oregon, and Washington, while they are increasing or at plateaus in Idaho, Montana, Utah, Nevada, and Wyoming, according to wastewater and emergency department data, as represented in estimates from the CDC’s forecasting center. Test positivity data show a steady decline in the Southwest (region 9), contrasted with a plateau in the Northwest (region 10).
We’re also seeing more states across the Northeast and Midwest report COVID-19 increases and higher levels, which is less surprising as these regions saw fewer outbreaks in the summer. The CDC’s forecasting center estimates that COVID-19 cases are “growing or likely growing” in 22 states as of October 28, including states across the Northeast, Mid-Atlantic, and Midwest, along with the West states noted above.
Wastewater data also show increasing coronavirus spread in parts of the Northeast and Midwest. The CDC’s wastewater dashboard estimates higher SARS-CoV-2 levels in the Northeast, on average, than any other region as of October 24, and reports recent increases in Massachusetts, New Jersey, New Hampshire, and Rhode Island. (Connecticut, which I flagged as a hot spot last week, reported a decline last week in the CDC’s data, but those are preliminary results that could change.)
Some data trackers have noted it’s unusual to see national COVID-19 averages increase in October. It’s true that, in the last few years, this time of year has typically included a relative lull between summer and winter surges. But it’s also important to note that SARS-CoV-2 is still a very new virus compared to others that have well-established seasonal patterns, and we still have more to learn about its behavior.
We do know, however, that high-quality, well-fitting masks go a long way in protecting people from coronavirus spread, as well as from other viruses like the flu — which is increasing across the U.S. right now, too. A recent paper in the journal Environmental Science & Technology offers another example of evidence in favor of masks. Singaporean researchers analyzed 40 outbreaks on airplanes, including 26 SARS-CoV-2 outbreaks and 14 flu A outbreaks, and their modeling found that if all passengers wore N95 or similar-quality masks, the risk of transmission would be “virtually eliminate[d]” for both viruses.
