Marc Johnson
@SolidEvidence
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Molecular virologist, Professor, and wastewater detective. Same handle on bsky. Ignore the check, I'm doing an experiment.
Columbia, Mo.
Joined January 2022
Do you think you've had long-term GI problems since having Covid? .We are performing a study examining the characteristics of viruses, specifically persistent SARS-CoV-2 infections, in stool samples. 1/3.
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That's it for now. We continue to recruit more sewersheds in partnership with @SecureBio. More updates to come. 10/10.
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This is fascinating. Although the rhinoviruses were usually surging in Spring, there was an outbreak of C42 in Fall of last year and it occurred in every one of the sewersheds coast-to-coast. Who knew?.9/
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And if you look at the other locations, most of the serotypes prevalent in Columbia this year were prevalent everywhere. 8/
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The rhinoviruses have been most prevalent in late Spring, and most of the prevalent serotypes in Columbia last year are not prevalent this year. 7/
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In the legend you can toggle the different sewersheds we are reporting (hopefully adding more soon). 6/
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First, we only listed the serotypes that have appeared in at least 4 consecutive samples. They are ordered based on when they first appeared in 4 consecutive samples. Time goes left to right, starting in 2024. Larger circles mean more of that serotype detected. 5/
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We debated how to best display this. There are over 100 rhinovirus serotypes, and we wanted to display their prevalence over space and time. Too many dimensions. This was our first stab at it. 4/
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As promised, we've now added a standalone readout of the rhinoviruses on our wastewater dashboard. 3/.
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Contrary to my prior assumptions, many of the most common pathogens are not everywhere, all the time. They occur in discrete waves, often nationwide. I wrote about this recently with Rhinoviruses, the most frequent cause of the common cold. 2/.
This is cool. I was poking around at the Rhinovirus (common cold) data and realized that my perception about these viruses was completely wrong. 1/
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I've always found this frustrating. You or your child has a respiratory infection. It's not flu or COVID. Your doctor can only tell you, 'you have a virus'. Could it be a little bit more specific?. We hope to help answer this question, non-invasively, and for free. 1/
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4 part. What movie featured this bridge?.Who directed?.What actor has been in the most films of that director?.What was that actor’s best film?
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This probably isn’t a surprise to real epidemiologists, but it was a revelation to me. Anyway, I think we’re going to have to add a rhinovirus breakdown on our dashboard. 16/16.
I’m thrilled to announce the update of our water surveillance dashboard. Many improvements, and our first substantial move into ‘OneHealth’. Read to the end to find the Easter Egg. 1/.
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Presumably each season we get a little bit of herd immunity against the serotype that is surging, so it is outcompeted the next season by an antigenically distinct serotype. 15/.
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This suggests that rhinoviruses really are more like influenza. It’s not a continuous swarm, but rather a bunch of discrete, nation-wide (world-wide?) surges of individual serotypes. 14/.
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More importantly, the serotypes surging in Columbia in 2025 appear to be surging everywhere. 13/
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Then I looked at the variation geographically. We weren’t sampling other sites in the 2024 season, but the serotypes that surged in Columbia in 2024 didn’t appear to surge anywhere in 2025. 12/
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That’s when I noticed something striking. Most (but not all) surges were in Spring, and the surges were season specific. While there were surges both years, the majority of the serotypes that surged in 2024 were replaced by different serotypes in 2025. 11/
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