Really, open office leads to more flu infections?? Based on her utterly anecdotal evidence of a bunch of her co-workers got sick. If that's the standard for evidence for the rest of the claims in this article, I would cast it aside.
Cornell did a study while back that found that communication gets worse with private offices. The pernicious thing is that employees' very perception of "frequent communication" changes depending on which kind of environment they're in. If they're in open plan it's several times a day often on the fly. If they have a private office, it plummets to "several times a week in a scheduled meeting". [1]
So that's consistent with private office people saying everything's fine -- because their very perception of the standard for team interaction has vastly diminished.
They also noted that office workers may be biased to favor plans that maximize their personal productivity even at the expense of team productivity, because their compensation is tied more to the former. Whereas management sees the bigger picture of both elements.
That may go a long way towards explaining why employees and management are often at odds over how to arrange the office.
(Having said that, by no means do I think that a constant barrage of noise in your face in a maximally open office is optimal. There are many degrees of openness, and I'm just pointing to evidence that private offices may swing too far in the other direction.)
[1] https://web.archive.org/web/20140615182702/http://iwsp.human...