First of all, I am not a doctor or a virus expert. Before I met Bubble, all I knew was selling products to factories, which includes worker safety tools.
This mask is called a surgical mask or surgeon mask. (At least in my country).
It usually has the FFP1 class and can block bacteria, but viruses are much smaller than bacteria, and this mask cannot block viruses. (Of course, the person in the photo may have worn the mask because he suffered from another disease, not Corona, which is usually a good filter against bacteria that can infect.)
If there is a danger in your country or if you want to take action against it, it should be “N95” (US Standard) or “EN149” (EU standard) and minimum “FFP2” class, and the really safe mask is definitely “FFP3”.
I hope you never have to buy.