The U.S. continues to see an estimated 1.1 million daily COVID infections with 2.2% of the population actively infectious as we descend from the peak of a 9th Covid wave.
Transmission will remain very high the rest of 2024.
Looking at the year-over-year graph, note that we're in uncharted territory for this point in the fall. Expect a very high "lull" in early November before the winter surge sets in.
As we have noted previously, our current estimates are likely slight underestimates given elevated school-based transmission and the CDC data standardization process.
Kids: They are smaller, and make smaller "contributions" to wastewater. Basically, it takes more sick kids to produce the average amount of wastewater virus to equate to an average infection (mostly in adults). This issue evens out over time, but it means the model may underestimate during back-to-school periods.
CDC: They describe the details of their process for standardizing data over time. It's very strong, much better than what most localized wastewater orgs or WWS do. It's a bit Dunning-Kruger to question basic wastewater scientists in doing the most fundamental components of their jobs, and the data continue to correlate >.90 with other metrics like Biobot. In comparing with other data, I take their estimates as spot on, but could also see arguments that they may underestimate transmission by 0-5%. It's something we always keep an eye on. Trust, but verify.
Transmission is magnitudes higher than much of the public realizes, so we focus on the big-picture view rather than quibbling over such issues that tend to balance out over time.
I hear @jlerollblues is considering weighting a model based on estimates of the proportion of infections in children. That's actually tougher to estimate than it sounds at first glance. You should key an eye on his models too and the work he and others are doing with the WHN.
Zooming in from the big picture, here's the past year of the pandemic.
🔹1.1 million daily infections
🔹Bimodal peak (Aug 10 & 24) of 1.3 million daily infections
🔹50-60% of transmission happens on the back end of waves
Continue to educate family, friends, and co-workers. Look at how the wave descends much more gradually than is arose. Many infections to come, and to try to prevent! Also, most people are not monitoring wastewater. They keep track of the cumulative "anecdata" of people they know sick or diagnosed with Covid recently. In their mind, the peak will feel like late October, when the cumulative count has really built up. You may find people more open to listening during the next month.
Estimated percentage of populations actively infectious:
Oklahoma: 8.9%
Oregon: 5.3%
New Hampshire: 5.3%
Note, estimates get less precise when focusing on smaller geographic units, and sometimes high estimates are revised in hindsight.
Also, while these figures may seem high, keep in mind that as one focuses on narrower units, the peak is more targeted, so local peaks see higher percentages than state peaks, which are higher than regional peaks, which are higher than national peaks. Smaller units have more leptokurtic transmission.
These are the present regional estimates in the U.S.
The West is coming down from a second peak this wave but still with approximately 2.8% of the region actively infectious.
The Northeast region saw atypically low transmission this wave, relative to other regions. That area may see a different pattern of transmission than the rest of the U.S. the next several months. For example, within the northeast region, the winter peak could be larger than other areas. However, expect to also see more localized units where instead of 2 big waves (late summer and winter), there is 1 big wave in late Nov / early December, or a bumpy wave in the months ahead, like the west just saw. Last winter, we often posted examples of the "weird" transmission patterns in some areas.
I'd keep a closer eye on local data if in the Northeast region.
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