In this Feb 7 interview, Trump says that covid is airborne. On March 10, the CDC downgraded its recommendations for PPE for healthcare workers from N95s to surgical masks on the basis that covid is not airborne. The driving factor was shortages.
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https://www.washingtonpost.com/health/2020/03/10/face-mask-shortage-prompts-cdc-loosen-coronavirus-guidance/ https://twitter.com/brianstelter/status/1303727882523602946

Even experts like the CDC have bent safety recommendations under the pressure of political & financial calculations-many times. That there is a deep mistrust of our leaders' abilities to keep us safe should not be a surprise. Trump is horrific but the story is bigger than him. 2/

Likewise, workers who are experts in their own conditions have done their own research & fought for real safety protections for themselves & others. It was nurses who challenged the CDC on this & fought for proper PPE that ended up saving lives. 3/ https://www.democracynow.org/2020/3/25/frontline_healthcare_workers_ppe_shortage_coronavirus