Thread by @froglet80

By now, you've probably seen the crowdfunding for a long covid biomarker test (). Maybe, like me, you've even donated to the cause. This is definitely exciting research, and much needed. 🧵longcovidbiomarkers.com

But, many folks are confused by what exactly its all about, so I want to try to clear that up up a bit by taking a look at their research correspondance, published in Lancet Microbes (). 🧵thelancet.com/journals/lanmi…

In this study, researchers compared the gene expression in blood cells from 48 people with long covid, to that of 12 people who had been previously infected with SARS-CoV-2 but did not report any ongoing symptoms as a control group. 🧵

The groups were matched according to age, sex, vaccination status, and time since infection. Average time since infection was 24 months for long covid and 21 months for controls. 🧵

The researchers examined nearly 800 host and viral genes, and found 212 that were different between the long covid and control groups. Adjustment to account for other variables narrowed this to 70 genes that showed significantly different levels of expression. 🧵

This included SARS-CoV-2 nucleocapsid, ORF7a, ORF3a, Mpro, and antisense ORF1ab RNA, host cell ACE2/TMPRSS2 receptors, DPP4/Furin proteases, and several related to memory B cells and platelets, which were all upregulated in the long covid group as compared to the contol group.🧵

Researchers say antisense ORF1ab indicates ongoing viral replication, and ACE2/TMPRSS2 and DPP4/Furin are related to SARS-CoV-2 viral infection. 🧵

Host FYN RNA and SARS-CoV-2 antisense RNA were found to be independent predictors of long covid, and together distinguished long covid from controls with 93.8% sensitivity and 91.7% specificity. 🧵

FYN RNA alone did so with 72.9% sensitivity and 100% specificity, and viral antisense RNA alone did so with 52.1% sensitivity and 91.7% specificity. 🧵

Sensitivity tells you how many of the actual cases a test is able to detect, and specificity tells you how many of the cases it detected are actual cases. 🧵

Researchers then determined participants viral load - defined as the sum of all viral transcripts in the sample. While viral RNA's were detected in both the long covid and control groups, that in the long covid group was significantly higher than that of controls. 🧵

The researchers also found that higher viral loads correlated with lower immunometabolism scores, and higher self reported anxiety and depression scores. 🧵

Finally, they found that increased number of comorbidities was correlated with higher viral loads, while number of vaccinations was correlated with lower viral loads. 🧵

Disclaimer: I'm not affiliated with the researchers or the orgs crowdfunding on their behalf, and I have no formal scientific or medical background. This is not medical advice and may contain errors.

If you find my threads useful, you can donate to support my work at ko-fi.com/froglet80

Adding this thread for #LongCovid #CommunityCare because people need support now while we wait for research ❤️