https://www.nature.com/articles/s41591-020-0843-2
Read the whole study at least through the Discussion, don't stop at the abstract. "Some health authorities recommend that masks be worn by ill individuals to prevent onward transmission (source control)4 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR4>,8 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR8>. Surgical face masks were originally introduced to protect patients from wound infection and contamination from surgeons (the wearer) during surgical procedures, and were later adopted to protect healthcare workers against acquiring infection from their patients. However, most of the existing evidence on the filtering efficacy of face masks and respirators comes from in vitro experiments with nonbiological particles9 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR9>,10 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR10>, which may not be generalizable to infectious respiratory virus droplets. There is little information on the efficacy of face masks in filtering respiratory viruses and reducing viral release from an individual with respiratory infections8 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR8>, and most research has focused on influenza11 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR11>,12 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR12>. Here we aimed to explore the importance of respiratory droplet and aerosol routes of transmission with a particular focus on coronaviruses, influenza viruses and rhinoviruses, by quantifying the amount of respiratory virus in exhaled breath of participants with medically attended ARIs and determining the potential efficacy of surgical face masks to prevent respiratory virus transmission." Key parts from the Discussion: " Among the samples collected without a face mask, we found that the majority of participants with influenza virus and coronavirus infection did not shed detectable virus in respiratory droplets or aerosols, whereas for rhinovirus we detected virus in aerosols in 19 of 34 (56%) participants (compared to 4 of 10 (40%) for coronavirus and 8 of 23 (35%) for influenza). For those who did shed virus in respiratory droplets and aerosols, viral load in both tended to be low (Fig. 1 <https://www.nature.com/articles/s41591-020-0843-2#Fig1>). Given the high collection efficiency of the G-II (ref. 19 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR19>) and given that each exhaled breath collection was conducted for 30 min, this might imply that prolonged close contact would be required for transmission to occur, even if transmission was primarily via aerosols, as has been described for rhinovirus colds." " The major limitation of our study was the large proportion of participants with undetectable viral shedding in exhaled breath for each of the viruses studied. We could have increased the sampling duration beyond 30 min to increase the viral shedding being captured, at the cost of acceptability in some participants. An alternative approach would be to invite participants to perform forced coughs during exhaled breath collection12 <https://www.nature.com/articles/s41591-020-0843-2#ref-CR12>. However, it was the aim of our present study to focus on recovering respiratory virus in exhaled breath in a real-life situation and we expected that some individuals during an acute respiratory illness would not cough much or at all." Here in South Carolina, we have about 2000 new cases reported. Let's say for each person with a positive case, there's another 10 that are infected, so perhaps there are 20,000 people out there in South Carolina with Wuhan Red Death (WRD). State population is about 5,000,000 which means that about 0.4% of the population MIGHT be walking around with WRD. So if I go to Costco, and there are about 200 people in the store, maybe one of them is infected. I'm about 50, in good health with none of the health conditions that "experts" think might make me more likely to get seriously ill or die from this, so I'm not too worried. If there is one person that is sick, and for 30 minutes of them breathing next to me there's about a 6 in 10 chance that they aren't expelling any virii in their breath, and they don't cough on me, then neither they nor I really need a mask, right? I don't stay next to anyone for 30 minutes in any store that I go to, generally I'm in and out in 30 minutes or less. ------------- Max Charleston SC _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
