No, that can’t be the case here, because a shockingly large proportion of people tested positive according to the article. (Thus, either the false positives are negligible, or the test employed has a an astronomical false positive rate (bad specificity)).
You're right, they get a positive result for almost all the population!
Wait, does that pass the smell test? Do prisions become huge flu hotspots as well? The Diamond Princess outbreak didn't have that kind of numbers... What's more likely at this point, the numbers from the article or human error?
My respects to anybody trying to do actual science with this kind of data in this kind of situation...
Densely crowded environment where people were unlikely to maintain social distancing, poor quality health care, probably poor quality sanitation. It seems reasonable to me that a prison would fare worse than a cruise ship.
Not quite this huge, but then again states generally try to get them flu vaccines. It's reasonably common for prisons to enact emergency measures to stop the spread of the flu.