[rickyc091]

It's useless in the sense that you can still contract the virus with a mask. Let's say they are using the surgeon's mask, someone can sneeze and it can get in through the side. The n95 has a better seal so that can prevent it, but what if someone sneezes and it gets into your eye. I would say some protection is better than nothing, but don't assume you will be protected from coronavirus 100%.

[umanwizard]

100% protection might be important to you personally, but it does not matter on a societal scale. What does matter is to decrease as much as possible the mean number of new people infected per sick person.

If that number is above 1, the growth is logistic (exponential in early stages), if it is lower but still above 1, it is exponential but with a longer doubling time ("flattening the curve"), and if it is below 1, cases will decrease.

[medbrane]

>but don't assume you will be protected from coronavirus 100%.

Washing hands does not protects you 100% so why bother?

[robbiep]

No! It’s bloody useless because you’re not just receiving it through your respiratory passage, but also eyes. And then you touch a surface which someone has put bodily fluids on and put your fingers in your mouth or rub your eyes.

Masks are excellent for stopping transmission for infectious patients however - because it catches particulates.

Current (and to be fair, there remains some debate but it seems it is really just the precautionary principle) evidence suggests that spread is by droplet. So a mask doesn’t help stop you receiving it. Definitely helps you stop transmitting it; definitely helps healthcare workers who are exposed to high titre loads, and will be working sick unlike the rest of the population,

But the average person can reduce both their transmission and infection by being vigilant with hand washing, masks if sneezing/coughing/isolating, not touching face/mouth/eyes

Leave the masks to the healthcare workers and the infected

[throwaway286]

If I accept your argument that a mask doesn't stop you from receiving it (which I doubt):

If it were a social norm to wear a mask during an outbreak, and 50% of the population did, it would reduce the spread of the virus greatly. Far from bloody useless. Americans are locked into individualistic thinking: "How will this benefit me?". Also consider asymptomatic transmission.