First, many health experts, including the surgeon general of the United States, told the public simultaneously that masks weren’t necessary for protecting the general public and that health care workers needed the dwindling supply. This contradiction confuses an ordinary listener. How do these masks magically protect the wearers only and only if they work in a particular field?

Third, of course masks work — maybe not perfectly and not all to the same degree, but they provide some protection. Their use has always been advised as part of the standard response to being around infected people, especially for people who may be vulnerable. World Health Organization officials wear masks during their news briefings. That was the reason I had bought a few in early January — I had been conducting research in Hong Kong, which has a lot of contact with mainland China, and expected to go back. I had studied and taught about the sociology of pandemics and knew from the SARS experience in 2003 that health officials in many high-risk Asian countries had advised wearing masks.

Fourth, the W.H.O. and the C.D.C. told the public to wear masks if they were sick. However, there is increasing evidence of asymptomatic transmission, especially through younger people who have milder cases and don’t know they are sick but are still infectious. Since the W.H.O. and the C.D.C. do say that masks lessen the chances that infected people will infect others, then everyone should use masks. If the public is told that only the sick people are to wear masks, then those who do wear them will be stigmatized and people may well avoid wearing them if it screams “I’m sick.” Further, it’s very difficult to be tested for Covid-19 in the United States. How are people supposed to know for sure when to mask up?

Fifth, places like Hong Kong and Taiwan that jumped to action early with social distancing and universal mask wearing have the pandemic under much greater control, despite having significant travel from mainland China. Hong Kong health officials credit universal mask wearing as part of the solution and recommend universal mask wearing. In fact, Taiwan responded to the coronavirus by immediately ramping up mask production

"Since Senator Romney sat next to Senator Paul for extended periods in recent days and consistent with [Centers for Disease Control and Prevention] guidance, the attending physician has ordered him to immediately self-quarantine and not to vote on the Senate floor," Romney's office said in a statement on Sunday.

He was preceded by Sen. Mike Lee (R-Utah), who became the first senator to announce he would self-quarantine because of Paul.

"Upon learning that my colleague Sen. Paul tested positive for COVID-19, I consulted the Attending Physician of the U.S. Congress Dr. Harding," Lee said in a statement. "Given the timing, proximity, and duration of my exposure to Sen. Paul, she directed me to self-quarantine for 14 days."

Human pathogenic coronaviruses (severe acute respiratory syndrome coronavirus [SARS-CoV] and SARS-CoV-2) bind to their target cells through angiotensin-converting enzyme 2 (ACE2), which is expressed by epithelial cells of the lung, intestine, kidney, and blood vessels.4

The expression of ACE2 is substantially increased in patients with type 1 or type 2 diabetes, who are treated with ACE inhibitors and angiotensin II type-I receptor blockers (ARBs).4
Hypertension is also treated with ACE inhibitors and ARBs, which results in an upregulation of ACE2.5
ACE2 can also be increased by thiazolidinediones and ibuprofen. These data suggest that ACE2 expression is increased in diabetes and treatment with ACE inhibitors and ARBs increases ACE2 expression. Consequently, the increased expression of ACE2 would facilitate infection with COVID-19. We therefore hypothesise that diabetes and hypertension treatment with ACE2-stimulating drugs increases the risk of developing severe and fatal COVID-1