The CDC put in a little aside, that "maybe" the corona virus was somehow different than every other virus. . .
. . . but that statement was unsupported by all the research.
They have known for fifty years that masks don't do shit. That is why BSL4 labs have the protocols that they do.
Anyone that has any amount of critical reading skills, would understand by reading the CDC's own literature, that their own experts don't believe masks contain an infectious spread anymore than a population that is not masked.
Volume 26, Number 5—May 2020
Policy Review
Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings—Personal Protective and Environmental Measures
Jingyi Xiao
1, Eunice Y. C. Shiu
1, Huizhi Gao, Jessica Y. Wong, Min W. Fong, Sukhyun Ryu, and Benjamin J. Cowling
Author affiliations: University of Hong Kong, Hong Kong, China
Pandemic Influenza—Personal Protective Measures
wwwnc.cdc.gov