We've headed from a false summit toward a larger peak in back-to-school transmission. Next week we'll know whether this is the largest or 2nd largest summer wave all-time. Expect 1.4-1.5 million daily infections at the peak.
This secondary peak is larger than anticipated previously, even when accounting for patterns of back-to-school transmission in prior years.
One, the West and South were peaking earlier, and the Northeast and Midwest have transmission picking up much faster than its falling off elsewhere. These are atypical regional differences.
Two, the 1-day isolation policy and general decline in school-based mitigation have unleashed transmission at higher levels than would be anticipated in prior years, even when accounting for the already-high levels of transmission as children went back to school.
Three, our model uses a combination of CDC and Biobot (former CDC contractor) data, using a 60% versus 40% mix for current case estimation. Biobot has not updated their data the prior two weeks without explanation. They were running much cooler than the CDC data, whether reflective of reality, or merely reporting delays. We have downgraded them to 20% in the model, and they will be downgraded further to 0% if they do not update their data this week.
You can take points 1 and 2 to account for the secondary and higher peak (shape of transmission), when models accounting for prior years would have suggested transmission slowing already, and point 3 accounting for a shift toward a slightly higher overall estimate of transmission.
PMC COVID-19 Forecasting Model, Sept 2, 2024
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This graph shows year-over-year transmission. It clarifies the unusual shape of the transmission distribution. A "peak" or false summit, followed by a very slight decline in transmission (negligible), then a 2nd (true) peak.
PMC COVID-19 Forecasting Model, Sept 2, 2024
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Presently, we estimate a peak at 1.4 million daily infections. Next week, we will have a much better sense. It could be in the 1.3-1.5 million range. There's about a 50% chance it will be the largest summer wave.
PMC COVID-19 Forecasting Model, Sept 2, 2024
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Happy Labor Day!
We're seeing higher transmission than during 91.6% of the pandemic, so COVID is very much not "over." In a gathering of 10 people of average risk, there would be a 1 in 4 chance someone has COVID if no special rules (testing, isolating, etc.).
Some schools still have not started yet and will begin tomorrow. Classrooms should presume someone has COVID. Mask, test, isolate until repeatedly negative.
PMC COVID-19 Forecasting Model, Sept 2, 2024
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Here's the heat map of transmission. You'll see a lack of a clear pattern because the South/West are slowing and the Midwest/Northeast are picking up.
Nationally, we see 1 in 35 people are actively infectious. The South is the highest with about 1 in 30 actively infectious.
PMC COVID-19 Forecasting Model, Sept 2, 2024
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Michigan (yellow line) has atypically low transmission. Happy to hear theories on this.
They have typically had unusual patterns of transmission. Perhaps the extended precautions during the 1st two years of the pandemic play some ongoing role.
About 0.9% are actively infectious in MI, about 1/3 the national average.
PMC COVID-19 Forecasting Model, Sept 2, 2024
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🌍Want to track COVID transmission accurately worldwide?
This PMC thread walks you through leading dashboards with information more up to date than WHO & EU directories.
🧵 1/
The Pandemic Mitigation Collaborative (PMC) Dashboard provides weekly COVID updates for the U.S., using wastewater surveillance derived case estimation models and analytic forecasting.
Our international directory includes official government dashboards & those developed by citizen scientists.
We exclude countries that have stopped reporting in the past 2-12 months even if on EU or WHO lists. We also exclude low-quality data from opt-in testing programs.
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🔥Biggest uptick since Jan
🔥1 in 167 actively infectious
🔥>2 million weekly infections
🔥700-1,200 resulting excess deaths from weekly infections
Track transmission closer to home w/our new state & international resources 👇
🧵1/6
PMC COVlD Dashboard, Jun 23, 2025 (U.S.)
🔹With >90% probability, we have entered the 11th COVlD wave.
🔹In a room of 50 people, there is already a 1 in 4 chance of an exposure.
🔹We expect nearly 15 million infections in the next month, and rising.
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PMC COVlD Dashboard, Jun 23, 2025 (U.S.)
We continue to expect transmission to break 500,000 daily infections in the U.S. around July 9th.
This is the same prediction as last week, as the forecast was dead on. Yet, there is considerably uncertainty around this timing.
Current transmission (red line) closely tracks that of summer 2023 (yellow line).
We expect to break 500k daily infections between July 9 and the end of July. Our current forecast...
2) PMC COVlD Dashboard, June 16, 2025 (U.S.)
Our current forecast is a bit more aggressive, predicting breaking 500k daily infections by July 9. The 2023 trend suggests end of July.
The 95% confidence interval shows large variation. Note that...
3) PMC COVlD Dashboard, June 16, 2025 (U.S.)
Note that CDC and Biobot both had retroactive corrections to last week's data, meaning the relative "lull" will last a little longer than the uncorrected data suggested. No big news on NB.1.8.1.
1) Here's a quick example of how the federal government is censoring the best scientific research. It's not just cuts to ongoing research.
It's new grant submissions too...
2) In January, I re-submitted a promising Covid/cancer grant to a non-federal funder. Hundreds of pages. Hundreds of hours of work. The best proposal I've submitted as a scientist.
Out of curiosity, I used Sean Mullen's Scan Assist tool to see how many banned words it had...
3) The proposal had 1,750 banned words. No big deal -- they're non-federal.
BUT I had planned to submit a smaller version to NIH this month as a "back up." Impossible!
It's not a matter of using a thesaurus or the find/replace command. The grant is on *Covid*...
CDC wastewater surveillance data show transmission rising. This is our forecast if transmission growth follows typical patterns.
The high & low estimates could be thought of as optimistic & pessimistic scenarios for NB.1.8.1.
2) PMC COVlD Dashboard, June 9, 2025
Notice that current transmission (red line, lower left) tracks closely with two years ago (yellow), slightly below the median (gray), and not far below last year (orange).
Consider each of these trajectories realistic scenarios.
3) PMC COVlD Dashboard, June 9, 2025
All indications are that we are headed into the start of an 11th national wave in the U.S.
We could percolate near the lull point another couple weeks (fingers crossed), but that scenario is becoming less likely.
National COVlD transmission recently fell to its lowest levels since the pre-Delta era.
It's go-time for many who have delayed medical appointments. The situation will likely get much worse in Jul/Aug.
2/ PMC COVlD Dashboard, June 2, 2025 (U.S.)
An estimated 1 in 211 are actively infectious. Most states are "low" or "very low" per CDC.
The situation remains serious even in a relative "lull." >1.5 million weekly estimated infections to result in 600-900 excess deaths.
3/ PMC COVlD Dashboard, June 2, 2025 (U.S.)
By the end of the month, we forecast an increase to 450k daily infections. If NB.1.8.1 takes off, closer to 600k. If overhyped, percolating only slightly higher.