Four years late. They knew it was airborne at the start and it took them four years to release this info. They could have prioritized upgrading indoor air in busy public places, but nah, better to just throw money at millionaires and hope something sticks. They opened up schools which were unsafe (rich schools had air filtration installed so the important people were protected) and they did it specifically to spread the disease after the vaccines were available, chasing the "herd immunity" fantasy. Maybe that's not working out as well as they thought it would?

The guidance emphasizes the importance of bringing in fresh outdoor air and ensuring that air conditioning and heating systems are operating properly, preferably with filters rated MERV-13 or higher. It also describes other steps that can be added, including air circulation, proper exhaust venting, air cleaners, and ultraviolet air treatment.

So HEPA filters, far-uvc, CR-Boxes are all a good idea. Small anecdote, but I have a couple CR-Boxes I set up and ran them when someone in my house was sick, and it never spread to me. A very rare occurance pre-pandemic.

Some co-workers and I have been advocating for proper air filtration for years now, and have basically been treated like kooks because the CDC has dragged their feet on this. Maybe now they'll listen to us?