This is very true. The only mask that actually filters viruses is the KN-95, every cloth mask or medical mask(usually blue) DOES NOT filter ou viruses.

Medical Masks are only for preventing Drs/Surgeons from getting droplets of sweat into a patient(bacteria). Medical Masks that Drs wear do NOT stop viruses from being pushes through the material. IF they are wearing a KN-95 Mask then it does, but all the blue/yellow masks everyone wears do not filter viruses(says so right on the product if you look at the box/instructions).