COVlD-19 levels are "Very High" or "High" in the majority of states, per the CDC.
This includes 27 states & D.C.
🔥🔥Very High:
Alaska, Hawai'i, California, Nevada, Idaho, Utah, S. Dakota, Nebraska, Texas, Louisiana, Indiana, Kentucky, Tennessee, Florida, S. Carolina, N. Carolina, D.C., Maryland, and Connecticut.
🔥High:
Washington state, Oregon, Montana, probably N. Dakota (imputed), Arkansas, Alabama, Virginia, Delaware, Rhode Island, and Massachusetts.
PMC estimates 1 in 38 people (2.7%) are actively infectious. Wastewater-derived case estimates suggest 1.3 million new daily infections.
PMC COVlD Report, Sep 15, 2025 (U.S.)
🧵2/7
Transmission is peaking nationally, but regional variation is common. Know what's happening in your state, and get the word out.
Note that the levels CDC calls "low" are still quite alarming.
PMC COVlD Report, Sep 15, 2025 (U.S.)
🧵3/7
Note that transmission is increasingly spreading from the South & West toward other areas. Know your state-level risk.
Transmission remains alarming even in areas CDC labels "Very Low" (e.g., Missouri, estimated 1 in 109).
PMC COVlD Report, Sep 15, 2025 (U.S.)
🧵4/7
"During COVlD" is today.
The U.S. experiences semi-annual waves. Wastewater-derived case estimates suggest the surge is peaking near 1.3 million new daily infections.
Note. CDC and Biobot made significant upward corrections to their levels reported last week, 5% and 31%, which pushes the estimated wave peak much higher.
PMC COVlD Report, Sep 15, 2025 (U.S.)
🧵5/7
Wastewater-derived case estimates suggest the U.S. is seeing approximately 9.0 million infections per week.
The past week's infections will result in up to 4,200 excess deaths.
Vaccination choice and access are being limited.
PMC COVlD Report, Sep 15, 2025 (U.S.)
🧵6/7
Current transmission (red) has closely tracked that of year 4 (yellow). Data through Sep 6 are shown.
If transmission drops sharply, like in year 4, Sep 6 would be the peak. Otherwise, we would have the latest U.S. summer peak so far.
PMC COVlD Report, Sep 15, 2025 (U.S.)
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Last week we noted the following as a plausible scenario. “A very large retroactive correction could shoot the peak substantially higher.” In fact, transmission was retroactively corrected upward, and that creates more uncertainty about the timing of the peak between the 6th and 13th.
The central projection for the current forecast appears to show a plateau heading into a gradual decline in transmission. However, it is best to consider this as an average scenario that must account for both a sudden drop as well as the possibility of continued increases.
Scenario #1: Peak on September 6 (approximately 40% chance). This would be similar to year 4 (see year-over-year graph), with a sharp, pointed peak. The peak would be estimated at approximately 1.25 million new daily infections.
Scenario #2: Peak on September 13 or late (approximately 60% chance). This would more resemble years 3 and 5, where transmission came down more gradually. The peak would be estimated at approximately 1.30 million new daily infections.
The truth may be somewhere in between, but the data only update weekly, so that level of precision is rarely possible. More importantly, transmission varies considerably regionally, so track local data closely.
Finally, note that significant transmission occurs post-peak, so ongoing multi-layered mitigation remains key. We advocate for national policy to increase vaccine eligibility and access across the nation, not merely in select states. I have volunteered to speak at ACIP, and if selected through the lottery system, will focus comments on ongoing and long-term excess mortality.
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During this 12th COVlD wave, the CDC reports 1-in-3 states have "High" or "Very High" levels.
PMC estimates the proportion of residents actively infectious (prevalence):
◾️USA: 1 in 67
◾️IA: 1 in 27
◾️MI: 1 in 25
◾️IN & CT: 1 in 23
◾️ME: 1 in 21
◾️OK & SD: 1 in 17
🧵1/
On average, Americans have have 5.0 cumulative SARS-CoV-2 infections.
This week's infections are expected to result in 1/4 to 1 million new #LongCOVID conditions and ≈2,000 excess deaths.
🧵2/
The wave peak is now estimated >10% higher than last week at 1.2 million new daily infections, nearly double the Delta wave.
We expect sustained high transmission (≈600,000 to 750,000 new daily infections) the next few weeks as COVlD circulates through schools/families.
🧵3/
Based on today's CDC & Biobot data, we estimate the following for the week of Jan 19:
🔸1 in 52 people in the U.S. actively infectious
🔸25% chance of exposure in a room of 15 ppl
🔸Nearly 1 million new daily infections
🔸5 cumulative infections per person all-time (avg)
🧵1/5
Transmission estimates have been marginally corrected upward.
11 states have Very High COVlD levels:
🔸PA: 1 in 25 estimated actively infectious
🔸MI: 1 in 23
🔸OH & KY: 1 in 22
🔸SD: 1 in 20
🔸NE & IA: 1 in 18
🔸IL & ME: 1 in 17
🔸IN: 1 in 16
🔸WV: 1 in 11
🧵2/5
We're in the middle of a 12th COVlD wave.
The peak has likely passed, but with students headed back to school, transmission is expected to remain high for at least the next several weeks.
The size of the winter COVlD wave has been revised upward as post-holiday data come in.
We estimated 1 in 55 people in the U.S. are actively infectious.
🔥WV: 1 in 14
🔥IN: 1 in 15
🔥MI & OH: 1 in 21
🔥MO: 1 in 22
🔥CT: 1 in 24
🔥KS: 1 in 25
🔥MA & IL: 1 in 27
Quick 🧵 1/4
Nationally, we are seeing an estimated 892,000 new daily SARS-CoV-2 infections, meaning a 1 in 4 chance of exposure in a room of 15 people. Risk varies considerably by state.
We are approaching an average of 5 infections per person since pandemic onset.
🧵 2/4
We are in the 12th COVlD wave of the U.S.
Current transmission is higher than 68% of all days since the pandemic onset in 2020.
🧵 3/4
You might not have heard, but the northeastern U.S. is in a COVlD surge.
We use wastewater levels to derive estimates of the proportion of people actively infectious in each state (prevalence), e.g., 1 in 24 people in Connecticut.
We told you that 109,000-175,000 Americans would died of COVID (excess deaths) in 2025.
Today, the CDC estimates 101,000 deaths/year (flat from Oct 2022 to Sep 2024), and likely higher when considering more nebulous non-acute excess deaths (heart attack 6 months later). 1/5
The CDC estimates are actually higher than I would have guessed, given their methodology, which models estimates based on easily countable factors in healthcare and expert input on multiplier values. It lends credence to the PMC upper bound of excess deaths of 175,000/yr.
2/5
What's troubling is the CDC has annual mortality flat. My expectation based on mortality displacement and Swiss Re data is that it should be declining. If is stays flat, we're running on something like breast+prostate cancer or lung cancer deaths per year in perpetuity.
3/5