“Respiratory pathogens on the outer surface of the used medical masks may result in self-contamination.”
June 3, 2019 | Chughtai, A.A., Stelzer-Braid, S., Rawlinson, W. et al. Contamination by respiratory viruses on outer surface of medical masks used by hospital healthcare workers. BMC Infect Dis 19, 491 (2019).| BMC Infectious Diseases
“Respiratory pathogens on the outer surface of the used medical masks may result in self-contamination. The risk is higher with longer duration of mask use (> 6 h) and with higher rates of clinical contact. Protocols on duration of mask use should specify a maximum time of continuous use, and should consider guidance in high contact settings. Viruses were isolated from the upper sections of around 10% samples, but other sections of masks may also be contaminated. HCWs should be aware of these risks in order to protect themselves and people around them.”
Masks Don’t Work: A Review of Science Relevant to COVID-19 Social Policy | Source
June 2020 |
“There have been extensive randomized controlled trial (RCT) studies, and meta-analysis reviews of RCT studies, which all show that masks and respirators do not work to prevent respiratory influenza-like illnesses, or respiratory illnesses believed to be transmitted by droplets and aerosol particles.
The present paper about masks illustrates the degree to which governments, the mainstream media, and institutional propagandists can decide to operate in a science vacuum, or select only incomplete science that serves their interests. Such recklessness is also certainly the case with the current global lockdown of over 1 billion people, an unprecedented experiment in medical and political history.
Here are key anchor points to the extensive scientific literature that establishes that wearing surgical masks and respirators (e.g., “N95″) does not reduce the risk of contracting a verified illness:”
• Jacobs, J. L. et al. (2009) “Use of surgical face masks to reduce the incidence of the common cold among health care workers in Japan: A randomized controlled trial,” American Journal of Infection Control, Volume 37, Issue 5, 417 – 419.
N95-masked health-care workers (HCW) were significantly more likely to experience headaches. Face mask use in HCW was not demonstrated to provide benefit in terms of cold symptoms or getting colds.
• Cowling, B. et al. (2010) “Face masks to prevent transmission of influenza virus: A systematic review,” Epidemiology and Infection, 138(4), 449-456. DOI:10.1017/S0950268809991658
None of the studies reviewed showed the benefit of wearing a mask in either HCW or community members in households (H). See summary Tables 1 and 2 therein.
• bin-Reza et al. (2012), “The use of masks and respirators to prevent transmission of influenza: a systematic review of the scientific evidence,” Influenza and Other Respiratory Viruses 6(4), 257-267.”There were 17 eligible studies. […] None of the studies established a conclusive relationship between mask/respirator use and protection against inﬂuenza infection.”
• Smith, J.D. et al. (2016) “Effectiveness of N95 respirators versus surgical masks in protecting health care workers from acute respiratory infection: a systematic review and meta-analysis”, CMAJ Mar 2016, cmaj.150835; DOI: 10.1503/cmaj.150835
“We identified 6 clinical studies … In the meta-analysis of the clinical studies, we found no significant difference between N95 respirators and surgical masks in the associated risk of (a) laboratory-confirmed respiratory infection, (b) influenza-like illness, or (c) reported work-place absenteeism.”
• Offeddu, V. et al. (2017) “Effectiveness of Masks and Respirators Against Respiratory Infections in Healthcare Workers: A Systematic Review and Meta-Analysis,” Clinical Infectious Diseases, Volume 65, Issue 11, 1 December 2017, Pages 1934-1942, https://doi.org/10.1093/cid/cix681
• Radonovich, L.J. et al. (2019) “N95 Respirators vs. Medical Masks for Preventing Influenza Among Health Care Personnel: A Randomized Clinical Trial”, JAMA. 2019; 322(9): 824-833. DOI:10.1001/jama.2019.11645
“Among 2862 randomized participants, 2371, completed the study and accounted for 5180 HCW-seasons. … Among outpatient health care personnel, N95 respirators vs. medical masks as worn by participants in this trial resulted in no significant difference in the incidence of laboratory-confirmed influenza.”
• Long, Y. et al. (2020) “Effectiveness of N95 respirators versus surgical masks against influenza: A systematic review and meta-analysis”, J Evid Based Med. 2020; 1- 9. https://doi.org/10.1111/jebm.12381
No RCT study with verified outcome shows a benefit for HCW or community members in households to wearing a mask or respirator. There is no such study. There are no exceptions. Likewise, no study exists that shows a benefit from a broad policy to wear masks in public.
Furthermore, if there were any benefit to wearing a mask, because of the blocking power against droplets and aerosol particles, then there should be more benefit from wearing a respirator (N95) compared to a surgical mask, yet several large meta-analyses, and all the RCT, prove that there is no such relative benefit. Masks and respirators do not work.
“Many potential harms may arise from broad public policies to wear masks, and the following unanswered questions arise:
• Do used and loaded masks become sources of enhanced transmission, for the wearer and others?
• Do masks become collectors and retainers of pathogens that the mask wearer would otherwise avoid when breathing without a mask?
• Are large droplets captured by a mask atomized or aerosolized into breathable components? Can virions escape an evaporating droplet stuck to a mask fiber?
• What are the dangers of bacterial growth on a used and loaded mask?
• How do pathogen-laden droplets interact with environmental dust and aerosols captured on the mask?
• What are long-term health effects on HCW, such as headaches, arising from impeded breathing?
• Are there negative social consequences to a masked society?
• Are there negative psychological consequences of wearing a mask, as a fear-based behavioral modification?
• What are the environmental consequences of mask manufacturing and disposal?
• Do the masks shed fibers or substances that are harmful when inhaled?”
“OSHA PPE Expert, Tammy Clark, and Occupational Environmental Safety Expert, Kristen Meghan, Talk Masks in a C-o-v-i-d world. What masks can and can’t do, their occupational hazards, and some of the myths behind the topic.”
Cloth Masks – dangerous to your health?
Over 30 Scientific Peer Reviewed Articles related to hazards and ineffectiveness of wearing masks: