Air Purifiers

My mom had used hers up until 6 months ago when she heard reports that it might be unsafe. She wasn’t experiencing any negative symptoms. In fact, it helped her respiratory condition. The IB commercials have also haven’t been airing on TV. Is there any truth to the rumors? She stopped using it for fear she might become sick. She almost died of pnumonia. Now she’s back to where she was sneezing and congested all the time.

We are buying an older home and though we are having the duct work and the central unit cleaned, I wanted to attach a whole house air purifier to it. UV lights-Hepa filters-electrostatic-combinations–my head is spinning! I need someone who really knows this stuff to tell me the truth. Help!!