COVID-19
Long COVID
One strange thing about human DNA is that there is DNA for viruses (called human endogenous retroviruses, HERV) embedded in our genome, presumably left over from ancient viral infections. Usually they stay there, but every once in a while they get loose. This paper from Spain (2024-07-31) reports that the levels of an virus called Torque Teno Mini Virus 9 (TTMV9) are higher in a subgroup of people with ME/CFS who have markers of elevated endogenous retrovirus activity. (They looked for high levels of lots of other common viruses, and didn’t find any.)
TTMV9 is relatively common, but not at the levels they saw in these ME/CFS people. Usually such high levels of TTMV9 is a marker of immune dysfunction.
From what I can tell, they didn’t think that TTMV9 was a HERV itself, but that TTMV9 unlocks HERVs.
They clearly don’t know how all the puzzle pieces fit together with TTMV9 and HERVs, but one thing that is clear is that high levels of TTMV9 ought to be a good biomarker for at least some types of ME/CFS, and if (some) Long COVID patients also have that biomarker, that tells us that there is (probably) a common mechanism between some ME/CFS and Long COVID.
This paper from Italy (2024-10-01) reports that children with Long COVID had higher levels of Chemokine (C-C motif) ligand 23 (CCL23). There’s not going to be a quiz on the name of the chemokine, just understand that it might also be a good biomarker, and that’s good news. (Also: the kids are not faking it.)
H5N1
Transmission
You might have heard about the case in Missouri which had no obvious bird or cattle connection. You might have heard about the six connections of that case who also came down with respiratory symptoms and whose blood is getting tested now for H5N1. You might be going WHAT IS THE HOLDUP?!?! IS THERE HUMAN TO HUMAN TRANSMISSION OR NOT?!?!?!
It turns out that it was NOT Hurricane Helene’s fault. This article (2024-10-02) reports that the US CDC is nervous that the test they have won’t properly pick up the Missouri case because it has some mutations they think wouldn’t get recognized by the test they had, so they need to make a new test. They also don’t have enough samples of the H5N1-with-mutation, so they are having to reverse-engineer the mutated strain a bit. Finally, they are worried about H1N1 antibodies giving a false-positive, so they are planning to deplete the samples of H1N1 before they test for H5N1. All very complicated.
I’m glad that they are being so careful, but I am a little surprised that they can’t just do whole-genome sequencing. But I’m not a biologist, what do I know?
This article (2024-10-04) reports that two dairy workers in California have tested positive for H5N1.
This article (2024-10-02) reports that there is one more herd in Idaho which has tested positive for bird flu; this article (2024-10-03) reports that eleven more California herds have tested positive, for a total of 255 herds in 14 states.
MERS
Oh boy. This press release from the World Health Organization reports that Saudi Arabia found someone with MERS, but they didn’t realize it until he’d gone to Pakistan. They found him and isolated him, and are doing aggressive contact tracing. No secondary cases have been found so far — but the dude didn’t have any contact with camels, so how did he catch it?
The good news is that Saudi Arabia caught it with routine hospital testing.