Megabear2,Well done keep going! Were we not being led to believe in the early pandemic days that the air con filter systems were being upgraded, I am sure the insider! referred to this at that time.
So why are so many people still coughing? We after our first cruise in 2016, having experienced a bad bout of coughing bronchitis illness, other 3 weeks, took certain steps on our next cruise and never suffered again, but others on our various cruises did. What we did was to take two hand towels, laid a dry one scrunched up on the floor, soaked the other one so it was dripping wet, and placed in on a wire coat hanger which we hung under the air con outlet in the roof, let it drip down on the one on the floor. We related this to lots of people that we met on board, over many cruise, and the thanks we received was proof that it worked.