C. Michael Gibson MD on Twitter: "Cambridge scientists tested 0.02 micron Bacteriophage MS2 particles (5 times smaller than the coronavirus) & compared homemade masks made of different materials to surgical masks. Surgical mask blocks 89% Vacuum cleaning bag 85% Dish Towel 73% T shirt 70% #macgyvercare https://t.co/RFEbhH1V5D" / Twitter #coronavirus https://twitter.com/CMichaelGibson/status/1239718351573843973