The sailors exchange uncertain glances, realizing they've probably already said too much, but the possibility that Quinn might know something piques their interest. Val speaks in a conspiratorial tone, "Well, you guys 're our second run. On the first run we had another prisoner had the same thing happen to 'im, and a few more were actin' pretty strange. We came in from the Shield as backup for Illya, but the fightin' was basically done when we showed up. The cap'n realized nobody was really takin' charge no more, so 'e made us a proper-sition that would make us some good money. Anyone 'oo wanted out was allowed ta leave, but no one wanted, cuz' everything was crazy everywhere an' we 'ad a tight crew. So, we kidnapped a bunch o' civilians tryin' to excape the city, an' we sold 'em in Zarga. Anyhow, I'm ramblin', but after we got the money, it dint sit well with a few folks, so they stayed in port. Almost stayed there m'self, but I needed the money, an' so I came for a secon' run. But then this here fella jus' did the same as the last, an' it's givin' me the heebie jeebies, y'know? Somethin' foul is goin' on in Illya, an' I want no part in it! So whaddaya know about that, eh?"
Spoiler: QuinnQuinn hasn't heard of anything like this before, with the exception of what has been happening in Illya in recent weeks. Whether or not it is a "curse", an illness, or something else, Quinn isn't sure, but the people in Illya have taken to calling it the "Nightmare Plague".
As for the rune, Quinn recognizes it from a book of research notes he read once.The book came in a box with a broken old astrologer's telescope that he acquired at an auction. The writing was fairly technical and prosaic for the most part, Quinn recalls, up until the page with this rune. This particular entry referred to a distant planet called Aucturn, and the entire tone of all entries from this point on is wild and often unintelligible. It seems whoever wrote it became obsessed with the matter and began having visions. The book ends very abruptly, so there is no telling what happened to the author, who is never identified. Based on what you had been able to decipher at the time, the author claims that the planet is in constant flux, and is alive, but little else is clear about it. Quinn is not familiar with any other reference to Auturn, or why the rune would be appearing on people's heads.
Spoiler: GeraldineGeri is not familiar with the rune, nor any curse that might have caused this. The closest thing she can think up is maybe some severe combination of Fevered Dreams and Dissolution, but even that seems a bit of a stretch.
Geri identifies a small, faded tattoo on Val's neck as the leaf of Gozreh. He doesn't strike her as a religious type, but probably superstitious.