Guys, don't get me wrong. OK naman to take reasonable precautions (wear a dust mask) if allergic ka, etc. but for this to trigger a panic buying of masks?
I'd say save those pharmacy stocks for those who really need them (the infirm [like mga may COPD], elderly, undergoing chemo, etc.). The rest of us can get by with non N95 rated masks.
Well, yes there's the possibility of pneumoco... (ok I'll skip the "doctor speak" and just say "health risk")
but that cr*p you're exposed to sa EDSA and other roads daily? That's much much worse than this (relatively) short exposure. And don't think that your airconditioned car & cabin filters make this some commuters' problem lang... reduced lang ang risk.
Yes, wear a mask if you need to. Limit time outdoors, but there's no need to be unduly alarmed. Yun lang naman.

When was the last time you changed them? If it's been a while, I suggest following your mechanic's...
Rubber boot question (repair or replace)