Now, more and more science shows that by wearing a mask to prevent the spread of the virus, you may also protect yourself. Further evidence suggests that knowledge about masks and their benefits is constantly evolving, just like the understanding of this pandemic.
The Centers for Disease Control and Prevention publicly acknowledged for the first time that the scientific bulletin published on its website this week wrote: “The benefits of masks come from the combination of source control and personal protection for mask wearers.”
John Brooks, the chief medical officer of the Centers for Disease Control and Prevention’s coronavirus response, told the Washington Post that there is an urgent need for a clear explanation, because widespread masking can help prevent a national lockdown.
He said that the Centers for Disease Control and Prevention released the scientific brief to address what the agency believes is a “short summary lacking strong scientific evidence to prove the benefits of cover-up.” The announcement marked the beginning of the agency’s renewed efforts to strengthen public information as infection rates in many US regions rose to record highs. The agency is now updating all communications about masks to include new information.
Brooks said that because the CDC cannot impose mandatory orders, the agency wants the public to understand that masks are “good for them.”
The new document attempts to spread persuasive information carrots to the public: The agency says that there is a “possibly complementary and possibly synergistic” relationship between controlling the source of infection of others and protecting oneself. In other words, the more people in the community wear masks, the greater the personal benefit.
Masks can form a barrier to prevent water droplets from flying when people breathe, talk, sing or cough. A study released last week showed that under experimental conditions, a simple fabric mask can block about three-quarters of the particles emitted by volunteers who cough.
However, it is also a logical assumption for researchers to study whether the mask may also block incoming particles. Brooks said that laboratory tests in recent months have shown that masks can filter out the types of particles that carry the virus.
CDC officials added that the personal protection of people wearing masks is not absolute. Brooks said: “The real benefit is that when all of us do this, we can reduce the covid-19 viral load in the community.”
In the nine months since the virus infected the United States, the CDC has received more and more criticism because its guidance on mask protection is not very clear, because it confuses scientific data with concerns about the availability of masks.
During the first wave of the pandemic, the survey showed that both Democrats and Republicans wore masks, although Democrats were more likely to wear masks. However, a few Americans are highly skeptical. This opposition became so obvious in the summer that online stores sold hundreds of fake “mask duty free” cards with images from the Ministry of Justice.
By midsummer, Republican congressmen began to encourage face masks. Senate Majority Leader Mitch McConnell (R-Ky.) said in late June that wearing a mask is “the single most important thing you can do” until a vaccine is available.
But President Trump rarely insists that Americans wear them. He often described masks as dispensable and was once misled as a “double-edged sword” because people might touch the fabric first and then the face.
Until July, after he covered his own photo with a mask on Twitter, there were few images of the president’s face covering his face.
Katherine White, a consumer behavior expert at the University of British Columbia, said: “In general, this seems to be a victory in attracting information from Republicans.” She said this is because conservatives are personally taken care of by themselves. Strong motivation.
Brooks, who oversees the release of the new announcement, said the language has been reviewed for a long time to ensure that the best evidence is agreed. He said that in this case, laboratory, epidemiological, and population-based studies have shown that wearing masks “has great benefits.”
During the pandemic, the evolution of scientific thinking about masks took place. Monica Gandhi, an infectious disease expert at the University of California, San Francisco, said that science has shown that facial coverings “have a higher thread count, more than one layer, and use “electrostatic filtering” masks such as surgical masks.” It provides the best protection.
Gandhi said: “Let the public know that masks protect you and others will make skeptics more convincing, saying that masks play an important role in reducing the spread and disease in public places19.”
It is not clear whether masks may reduce the severity of the disease by suppressing some but not all incoming virus particles. On September 8, Gandhi and her UCSF colleague George Rutherford (George Rutherford) suggested that the dose of the virus that people are exposed to may affect the severity of the disease. Scientists say that the mask can filter out enough water droplets, which in some cases can lead to asymptomatic or mild illness and a certain degree of immunity.
On October 23, some other famous experts, including Angela Rasmussen of Columbia University and Saskia Popescu of George Mason University, pointed out in a letter to the editor that the science is preliminary and it is just a hypothesis that people wearing masks inhale a small amount. virus.
The CDC did not mention this theory in its announcement this week. The agency emphasized that this update did not reflect the agency’s changes to the recommendations on wearing masks.
Brooks said: “Our guidance is still the same.” “More data supports this, and it highlights the personal protection we want to ensure that people understand.”