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Coronavirus masks: What’s the latest evidence?

We analyzed over 80 studies to help answer your mask questions: efficacy of different types, storage, downsides, and more.

Masks are most efficacious when worn by the infected, but some of them can also help when worn by the healthy. Home mask disinfection may be dangerous if done wrong, but there’s some evidence developing for disinfection in a clinical setting.

Our evidence-based analysis on coronavirus masks: what’s the latest evidence? features 89 unique references to scientific papers.

Research analysis led by .
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Examine.com Team
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References

  1. ^ Mitze et al. Face masks considerably reduce COVID-19 cases in Germany: A synthetic control method approach. IZA Discussion Paper Series (ISSN: 2365-9793). (2020-06)
  2. ^ Rengasamy S, Eimer B, Shaffer RE. Simple respiratory protection--evaluation of the filtration performance of cloth masks and common fabric materials against 20-1000 nm size particles. Ann Occup Hyg. (2010)
  3. ^ a b c Smith JD, et al. Effectiveness of N95 respirators versus surgical masks in protecting health care workers from acute respiratory infection: a systematic review and meta-analysis. CMAJ. (2016)
  4. ^ Feng S, et al. Rational use of face masks in the COVID-19 pandemic. Lancet Respir Med. (2020)
  5. ^ a b Abd-Elsayed A, Karri J. Utility of Substandard Face Mask Options for Health Care Workers During the COVID-19 Pandemic. Anesth Analg. (2020)
  6. ^ a b Bin-Reza F, et al. The use of masks and respirators to prevent transmission of influenza: a systematic review of the scientific evidence. Influenza Other Respir Viruses. (2012)
  7. ^ a b c Bartoszko JJ, et al. Medical Masks vs N95 Respirators for Preventing COVID-19 in Health Care Workers A Systematic Review and Meta-Analysis of Randomized Trials. Influenza Other Respir Viruses. (2020)
  8. ^ a b Eninger RM, et al. Filter performance of n99 and n95 facepiece respirators against viruses and ultrafine particles. Ann Occup Hyg. (2008)
  9. ^ Kim JM, et al. Identification of Coronavirus Isolated from a Patient in Korea with COVID-19. Osong Public Health Res Perspect. (2020)
  10. ^ Ksiazek TG, et al. A novel coronavirus associated with severe acute respiratory syndrome. N Engl J Med. (2003)
  11. ^ a b Oberg T, Brosseau LM. Surgical mask filter and fit performance. Am J Infect Control. (2008)
  12. ^ Lee SA, Grinshpun SA, Reponen T. Respiratory performance offered by N95 respirators and surgical masks: human subject evaluation with NaCl aerosol representing bacterial and viral particle size range. Ann Occup Hyg. (2008)
  13. ^ a b Wu P, et al. Characteristics of Ocular Findings of Patients With Coronavirus Disease 2019 (COVID-19) in Hubei Province, China. JAMA Ophthalmol. (2020)
  14. ^ a b Wang Q, Yu C. Letter to editor: Role of masks/respirator protection against 2019-novel coronavirus (COVID-19). Infect Control Hosp Epidemiol. (2020)
  15. ^ Ng K, et al. COVID-19 and the Risk to Health Care Workers: A Case Report. Ann Intern Med. (2020)
  16. ^ a b MacIntyre CR, et al. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ Open. (2015)
  17. ^ Bourouiba L. Turbulent Gas Clouds and Respiratory Pathogen Emissions: Potential Implications for Reducing Transmission of COVID-19. JAMA. (2020)
  18. ^ a b Cowling BJ, et al. Face masks to prevent transmission of influenza virus: a systematic review. Epidemiol Infect. (2010)
  19. ^ Nishiura H, et al. Rapid awareness and transmission of severe acute respiratory syndrome in Hanoi French Hospital, Vietnam. Am J Trop Med Hyg. (2005)
  20. ^ Zhang L, et al. Protection by face masks against influenza A(H1N1)pdm09 virus on trans-Pacific passenger aircraft, 2009. Emerg Infect Dis. (2013)
  21. ^ MacIntyre CR, et al. Face mask use and control of respiratory virus transmission in households. Emerg Infect Dis. (2009)
  22. ^ Saunders-Hastings P, et al. Effectiveness of personal protective measures in reducing pandemic influenza transmission: A systematic review and meta-analysis. Epidemics. (2017)
  23. ^ MacIntyre CR, et al. Cluster randomised controlled trial to examine medical mask use as source control for people with respiratory illness. BMJ Open. (2016)
  24. ^ Stockwell RE, et al. Face Masks Reduce the Release of Pseudomonas aeruginosa Cough Aerosols When Worn for Clinically Relevant Periods. Am J Respir Crit Care Med. (2018)
  25. ^ Dharmadhikari AS, et al. Surgical face masks worn by patients with multidrug-resistant tuberculosis: impact on infectivity of air on a hospital ward. Am J Respir Crit Care Med. (2012)
  26. ^ Sung AD, et al. Universal Mask Usage for Reduction of Respiratory Viral Infections After Stem Cell Transplant: A Prospective Trial. Clin Infect Dis. (2016)
  27. ^ Makison Booth C, et al. Effectiveness of surgical masks against influenza bioaerosols. J Hosp Infect. (2013)
  28. ^ Johnson DF, et al. A quantitative assessment of the efficacy of surgical and N95 masks to filter influenza virus in patients with acute influenza infection. Clin Infect Dis. (2009)
  29. ^ Hui DS, et al. Exhaled air dispersion during coughing with and without wearing a surgical or N95 mask. PLoS One. (2012)
  30. ^ MacIntyre CR, Chughtai AA. Facemasks for the prevention of infection in healthcare and community settings. BMJ. (2015)
  31. ^ Gralton J, McLaws ML. Protecting healthcare workers from pandemic influenza: N95 or surgical masks?. Crit Care Med. (2010)
  32. ^ Long Y, et al. Effectiveness of N95 respirators versus surgical masks against influenza: A systematic review and meta-analysis. J Evid Based Med. (2020)
  33. ^ Radonovich LJ Jr, et al. N95 Respirators vs Medical Masks for Preventing Influenza Among Health Care Personnel: A Randomized Clinical Trial. JAMA. (2019)
  34. ^ Loeb M, et al. Surgical mask vs N95 respirator for preventing influenza among health care workers: a randomized trial. JAMA. (2009)
  35. ^ MacIntyre CR, et al. A randomized clinical trial of three options for N95 respirators and medical masks in health workers. Am J Respir Crit Care Med. (2013)
  36. ^ MacIntyre CR, et al. Efficacy of face masks and respirators in preventing upper respiratory tract bacterial colonization and co-infection in hospital healthcare workers. Prev Med. (2014)
  37. ^ MacIntyre CR, et al. The efficacy of medical masks and respirators against respiratory infection in healthcare workers. Influenza Other Respir Viruses. (2017)
  38. ^ Howard et al. Face masks against COVID-19: An evidence review. Preprints. (2020-07-12)
  39. ^ Christian J. Kähler and Rainer Hain. Fundamental protective mechanisms of face masks against droplet infections. Journal of Aerosol Science. (2020-10)
  40. ^ Liu X, Zhang S. COVID-19: Face masks and human-to-human transmission. Influenza Other Respir Viruses. (2020)
  41. ^ Leung N et al.. Respiratory virus shedding in exhaled breath and efficacy of face masks. Nat Med. (2020-04-03)
  42. ^ Jennings LC, Dick EC. Transmission and control of rhinovirus colds. Eur J Epidemiol. (1987)
  43. ^ Davies A, et al. Testing the efficacy of homemade masks: would they protect in an influenza pandemic?. Disaster Med Public Health Prep. (2013)
  44. ^ Myers WR, et al. Workplace protection factor measurements on powered air-purifying respirators at a secondary lead smelter: results and discussion. Am Ind Hyg Assoc J. (1984)
  45. ^ Yan J, et al. Modeling the Effectiveness of Respiratory Protective Devices in Reducing Influenza Outbreak. Risk Anal. (2019)
  46. ^ Milton DK, et al. Influenza virus aerosols in human exhaled breath: particle size, culturability, and effect of surgical masks. PLoS Pathog. (2013)
  47. ^ Aiello AE, et al. Mask use, hand hygiene, and seasonal influenza-like illness among young adults: a randomized intervention trial. J Infect Dis. (2010)
  48. ^ Cowling BJ, et al. Preliminary findings of a randomized trial of non-pharmaceutical interventions to prevent influenza transmission in households. PLoS One. (2008)
  49. ^ Suess T, et al. The role of facemasks and hand hygiene in the prevention of influenza transmission in households: results from a cluster randomised trial; Berlin, Germany, 2009-2011. BMC Infect Dis. (2012)
  50. ^ Aiello AE, et al. Facemasks, hand hygiene, and influenza among young adults: a randomized intervention trial. PLoS One. (2012)
  51. ^ Canini L, et al. Surgical mask to prevent influenza transmission in households: a cluster randomized trial. PLoS One. (2010)
  52. ^ Lau JT, et al. SARS transmission, risk factors, and prevention in Hong Kong. Emerg Infect Dis. (2004)
  53. ^ Wu J, et al. Risk factors for SARS among persons without known contact with SARS patients, Beijing, China. Emerg Infect Dis. (2004)
  54. ^ Barasheed O, et al. Uptake and effectiveness of facemask against respiratory infections at mass gatherings: a systematic review. Int J Infect Dis. (2016)
  55. ^ Wang M, et al. A cluster-randomised controlled trial to test the efficacy of facemasks in preventing respiratory viral infection among Hajj pilgrims. J Epidemiol Glob Health. (2015)
  56. ^ Barasheed O, et al. Pilot Randomised Controlled Trial to Test Effectiveness of Facemasks in Preventing Influenza-like Illness Transmission among Australian Hajj Pilgrims in 2011. Infect Disord Drug Targets. (2014)
  57. ^ Rashid H, et al. Unmasking masks in Makkah: preventing influenza at Hajj. Clin Infect Dis. (2012)
  58. ^ a b Rebmann T, Carrico R, Wang J. Physiologic and other effects and compliance with long-term respirator use among medical intensive care unit nurses. Am J Infect Control. (2013)
  59. ^ Fisher EM, Shaffer RE. Considerations for recommending extended use and limited reuse of filtering facepiece respirators in health care settings. J Occup Environ Hyg. (2014)
  60. ^ Wiwanitkit V. Face mask decontamination and reuse: is it ok?. Am J Infect Control. (2011)
  61. ^ Neupane BB, et al. Optical microscopic study of surface morphology and filtering efficiency of face masks. PeerJ. (2019)
  62. ^ a b Viscusi DJ, et al. Evaluation of five decontamination methods for filtering facepiece respirators. Ann Occup Hyg. (2009)
  63. ^ Tseng CC, Li CS. Inactivation of viruses on surfaces by ultraviolet germicidal irradiation. J Occup Environ Hyg. (2007)
  64. ^ Mills D, et al. Ultraviolet germicidal irradiation of influenza-contaminated N95 filtering facepiece respirators. Am J Infect Control. (2018)
  65. ^ Lindsley WG, et al. Effects of Ultraviolet Germicidal Irradiation (UVGI) on N95 Respirator Filtration Performance and Structural Integrity. J Occup Environ Hyg. (2015)
  66. ^ Darnell ME, Taylor DR. Evaluation of inactivation methods for severe acute respiratory syndrome coronavirus in noncellular blood products. Transfusion. (2006)
  67. ^ Eickmann M, et al. Inactivation of three emerging viruses - severe acute respiratory syndrome coronavirus, Crimean-Congo haemorrhagic fever virus and Nipah virus - in platelet concentrates by ultraviolet C light and in plasma by methylene blue plus visible light. Vox Sang. (2020)
  68. ^ Trevisan A, et al. Unusual high exposure to ultraviolet-C radiation. Photochem Photobiol. (2006)
  69. ^ Lore MB, et al. Effectiveness of three decontamination treatments against influenza virus applied to filtering facepiece respirators. Ann Occup Hyg. (2012)
  70. ^ Duan SM, et al. Stability of SARS coronavirus in human specimens and environment and its sensitivity to heating and UV irradiation. Biomed Environ Sci. (2003)
  71. ^ Nathan N. Waste Not, Want Not: The Re-Usability of N95 Masks. Anesth Analg. (2020)
  72. ^ Elhafi G, et al. Microwave or autoclave treatments destroy the infectivity of infectious bronchitis virus and avian pneumovirus but allow detection by reverse transcriptase-polymerase chain reaction. Avian Pathol. (2004)
  73. ^ Siddharta A, et al. Inactivation of HCV and HIV by microwave: a novel approach for prevention of virus transmission among people who inject drugs. Sci Rep. (2016)
  74. ^ Casanova LM, et al. Effects of air temperature and relative humidity on coronavirus survival on surfaces. Appl Environ Microbiol. (2010)
  75. ^ Lamarre A, Talbot PJ. Effect of pH and temperature on the infectivity of human coronavirus 229E. Can J Microbiol. (1989)
  76. ^ a b Tan IK, Bhatt SB. Determining the expiratory time constant. Crit Care Med. (1996)
  77. ^ Jy Ong J, et al. Headaches Associated with Personal Protective Equipment - A Cross-sectional Study Amongst Frontline Healthcare Workers During COVID-19 (HAPPE Study). Headache. (2020)
  78. ^ Krymchantowski AV. Headaches due to external compression. Curr Pain Headache Rep. (2010)
  79. ^ Lim EC, et al. Headaches and the N95 face-mask amongst healthcare providers. Acta Neurol Scand. (2006)
  80. ^ Jacobson RI. More "goggle headache": supraorbital neuralgia. N Engl J Med. (1983)
  81. ^ Pestronk A, Pestronk S. Goggle migraine. N Engl J Med. (1983)
  82. ^ Khoo KL, et al. The changing face of healthcare worker perceptions on powered air-purifying respirators during the SARS outbreak. Respirology. (2005)
  83. ^ Sandaradura I, et al. A close shave? Performance of P2/N95 respirators in healthcare workers with facial hair: results of the BEARDS (BEnchmarking Adequate Respiratory DefenceS) study. J Hosp Infect. (2020)
  84. ^ Goh DYT, et al. A randomised clinical trial to evaluate the safety, fit, comfort of a novel N95 mask in children. Sci Rep. (2019)
  85. ^ O'Malley P, Rainford J, Thompson A. Transparency during public health emergencies: from rhetoric to reality. Bull World Health Organ. (2009)
  86. ^ Daniels N. Accountability for reasonableness. BMJ. (2000)
  87. ^ Thompson AK, et al. Pandemic influenza preparedness: an ethical framework to guide decision-making. BMC Med Ethics. (2006)
  88. ^ Kenyon C. Widespread use of face masks in public may slow the spread of SARS CoV-2: an ecological study. medRxiv. (2020-04-06)
  89. ^ a b Bai Y, et al. Presumed Asymptomatic Carrier Transmission of COVID-19. JAMA. (2020)