156. Mask, COVID-19, Annals of Internal Medicine from Questioning Medicine

Masks!!!! Do they prevent COVID19 transmission by preventing spread from infected people to others OR do they work by protecting wearers OR is it both.

We now have an answer to the second question, Do the mask work by protecting the wearers and in short the answer is no.

Fresh out november 18.

The DANMASK-19 trial

It a trial designed to examine the masks' protective effect.

Spring 2020 in Denmark, Social distancing recommendations were in effect, but masks were not recommended, they were rarely worn outside of hospitals, and the infection rate was modest around 2% per month which is pretty close to what we were seeing because remember we were around 1-3% here in american depending on where you lived with some places much much higher like New york but many places down to almost 0% like the fly over states and even places like salt lake city.

The endpoint was infection in the mask wearer!!! NOT infection in their contacts or the overall community infection rate.

This study enrolled 6024 adults who spent at least 3 hours outside their homes per day, had occupations that did not require masks, and did not have a previous known diagnosis of SARS-CoV-2 infection.

All participants were told to follow social distancing measures but randomized to wear or not wear a mask when outside the home.

The primary outcome was SARS-CoV-2 infection, defined as a positive COVID nasal swab OR development of a positive COVID antibody test OR a hospital-based diagnosis of COVID-19.

They powered it to find a 50% reduction in infection risk

After 1 month of follow-up, 1.8% (42 of 2392) of participants in the mask group and 2.1% (53 of 2470) in the control group developed COVID19 infection (risk difference, −0.3 percentage point [95% CI, −1.2 to 0.4 percentage point] [P = 0.38]; odds ratio, 0.82 [CI, 0.54 to 1.23] [P = 0.33]).

THERE WAS NO DIFFERENCE!!

BOOM FIRST RCT we have on wearing mask during COVID19 pandemic and it says that wearing a mask does not protect you from getting COVID19.

As with all trials which dont show what you want them to show there are people already knocking this well done trial. This is a common event and happens often in the cardiology or vit d literature. The study doesnt show what they want to they use very simplistic thinking to knock it down. Don’t get me wrong it has it’s flaws but use your brain to think deep and dont use the easy answer because they are not correct, in my opinion

Here are some of the things I have heard people say

1- “Well the study only looked at the effect of recommending mask use, not the effect of actually wearing them.”-In the study people were recommended to wear a mask not required to wear one-- yes, but that goes for every study—we recommend you to take a pill not the effect of actually taking them since we have no way of knowing they actually took them…This is every trial and either you believe in science and trials or you dont and you cant now all of a sudden not believe in medicine because the trial didnt show what you wanted.

2- How do we know people are wearing mask accurately??? Well in the trial 46% wore the mask as recommended and 47% wore it "predominantly as recommended," for a total of 93%. That is probably better than america, go to the grocery store and just walk around you might need more noses than heads of lettuce.

3- Some people say well this was done in denmark, we live in america so you cant use this evidence in america. This arguement works for some conditions and some treatments but I have no idea how this arguements works for wearing and not wearing mask. Unless there is a cultural difference in Denmark I am not awar(continued)

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