Raina MacIntyre has led the largest body of clinical research on face masks and respirators in front line health workers internationally. Research in this area includes complex cluster RCTs of efficacy of different PPE products, design of more efficient PPE, and modelling to inform policy options.The literature is abundant with RCTs on pharmaceutical interventions for infection prevention, but there is very little evidence on efficacy of non-pharmaceutical measures, of which facemasks, respirators and other personal protective equipment (PPE) are the most important. Prior to 2009, there were no RCTs of any PPE published, yet PPE is among the few available interventions to protect frontline workers in an emergent epidemic or pandemic where drugs and vaccines may be unavailable, or delayed in development. Facemasks and respirators are widely used in the hospital setting to protect hospital healthcare workers (HCWs) from nosocomial infections. Facemasks are mostly used to avoid contact with splashes and sprays of body fluids or blood, and to prevent spread of infections from sick patients. Respirators are designed for respiratory protection widely accepted in healthcare setting to protect HCWs from acquiring respiratory infections. Respiratory Protection Standards of many countries (rich and lower income) are inconsistent and in some cases have not been updated for 20 years. One of the main reasons for this is the lack of research data on effectiveness of respiratory protection devices and HCW practices. Raina and her team set out to address this important evidence gap with this body of work, which includes 5 large RCTs on facemasks and respirators and numerous other studies. Raina's aerosol dynamics lab has also generated a range of research on the trajectory of human respiratory emissions and the ability of masks to block these. We are also studying novel fabrics for better re-usable masks and PPE, and optimal design of cloth masks. In 2020 we started studying the efficacy of masks in preventing health effects of bushfire smoke. She works with mask manufacturers in the US and Australia, and established an interdisciplinary aerosol lab in 2018, which has generated critical research during the COVID-19 pandemic. She heads an inter-disciplinary NHMRC Centre for Research Excellence, BREATHE, on mitigating airborne threats to health. In 2016 she outlined her vision for sustainable, affordable and high-performance masks to improve equity globally, and this work has been underway at UNSW, with a range of materials tested with reduced graphene oxide and a combination silver or copper nanoparticles.
Facemasks for infection prevention explained
This video explains the large body of research conducted by Prof Raina MacIntyre and collaborators on face masks and respirators for prevention of infection. It covers surgical masks, respirators and cloth masks. See below for details of published research in respiratory protection.
Randomised clinical trials
- MacIntyre CR, Chughtai AA, Rahman B, Peng Y, Zhang Y, Seale H, et al. The efficacy of medical masks and respirators against respiratory infection in health workers. Influenza and Other Respiratory Viruses, 11 Aug 2017. doi:10.1111/irv.12474
- *MacIntyre CR, Zhang Y, Chughtai AA, Seale H, Zhang D, Chu Y, Zhang H, Rahman B, Wang Q. Cluster randomised controlled trial to examine medical mask use as source control for people with respiratory illness. BMJ Open 2016;6:e012330.
- *MacIntyre CR, Seale H, Dung TC, Nguyen Tran Hien NT, Nga PT, Chughtai AA, Rahman B, Dwyer DE, Wang Q. A cluster randomised trial of cloth masks compared with medical masks in healthcare workers. BMJ Open 2015;5:e006577 doi:10.1136/bmjopen-2014-006577 0.1093/annhyg/mew008.
- MacIntyre CR, Dung TC, Chughtai AA, Seale H, Rahman B. Contamination and washing of cloth masks and risk of infection among hospital health workers in Vietnam: a post hoc analysis of a randomised controlled trial. BMJ Open. 2020 Sep 28;10(9):e042045. doi: 10.1136/bmjopen-2020-042045
- *MacIntyre CR, Wang Q, Seale H, Peng Y, Shi W, Gao Z, Rahman B, Zhang Y, Wang X, Newall AT, Heywood A, Dwyer D. A randomised clinical trial of three options for N95 respirators and medical masks in health workers. American Journal of Respiratory and Critical Care Medicine 2013; 187(9): 960-966.
- MacIntyre CR, Wang Q, Cauchemez S, Seale H, Dwyer D E, Yang P, Shi W, Gao Z, Pang X, Zhang Y, Wang X, Duan W, Rahman B, Ferguson N. A cluster randomized clinical trial comparing fit tested and non-fit tested N95 respirators to medical masks to prevent respiratory virus infection in healthcare workers. Influenza and Other respiratory Viruses. 2011; 5(3):170-9, 2011 May.
- MacIntyre CR, Cauchemez S, Dwyer DE, Seale H, Cheung P, Browne G, Fasher M, Wood J, Gao Z, Booy R, Ferguson N, Effectiveness of face mask use to control respiratory virus transmission in households, Emerging Infectious Diseases. Vol. 15, No. Pg 233-41. 2 February 2009
- *MacIntyre CR, Wang Q, Rahman B, Seale H, Ridda I, Gao Z, Yang P, Shi W, Pang X, Zhang Y, Moa A, Dwyer DE. Efficacy of face masks and respirators in preventing upper respiratory tract bacterial colonization and co-infection in hospital healthcare workers. Preventive Medicine 2014; 62: p. 1-7.
- MacIntyre CR, Chughtai AA, Seale H, Dwyer DE, Quanyi W. HUMAN CORONAVIRUS DATA FROM FOUR CLINICAL TRIALS OF MASKS AND RESPIRATORS. International Journal of Infectious Diseases. 2020. Online first
Other mask and aerosol dynamics research
Bahl P; Doolan C; De Silva C; Chughtai AA; Bourouiba L; Macintyre CR, 2022, 'Airborne or Droplet Precautions for Health Workers Treating Coronavirus Disease 2019?', Journal of Infectious Diseases, vol. 225, pp. 1561 - 1568, http://dx.doi.org/10.1093/infdis/jiaa189
Tang S; Li X; Ding P; Mao Y; Deng F; Cha Y; Zhuang S; Ding C; Wang J; Wang Y; Zhao X; Jones RM; Kan B; MacIntyre CR; Xu D; Shi X, 2022, 'Filtration efficiency of face masks against aerosolized surrogate SARS-CoV-2 at different social distances', Science Bulletin, vol. 67, pp. 565 - 568, http://dx.doi.org/10.1016/j.scib.2021.12.017
Li X; Ding P; Deng F; Mao Y; Zhou L; Ding C; Wang Y; Luo Y; Zhou Y; MacIntyre CR; Tang S; Xu D; Shi X, 2022, 'Wearing time and respiratory volume affect the filtration efficiency of masks against aerosols at different sizes', Environmental Technology and Innovation, vol. 25, pp. 102165, http://dx.doi.org/10.1016/j.eti.2021.102165
Quigley A; Nguyen PY; Stone H; Heslop DJ; Chughtai AA; MacIntyre CR, 2022, 'Estimated Mask Use and Temporal Relationship to COVID-19 Epidemiology of Black Lives Matter Protests in 12 Cities', Journal of Racial and Ethnic Health Disparities, http://dx.doi.org/10.1007/s40615-022-01308-4
Kalaiselvan P; Tummanapalli SS; Kumar Vijay A; Bahl P; MacIntyre CR; Willcox MDP, 2022, 'The ability of face masks to reduce transmission of microbes', Clinical and Experimental Optometry, vol. 105, pp. 214 - 221, http://dx.doi.org/10.1080/08164622.2021.1971050
Zhang Y, Quigley A, Wang Q, MacIntyre CR. Non-pharmaceutical interventions during the roll out of covid-19 vaccines. BMJ. 2021 Dec 1;375:n2314. doi: 10.1136/bmj.n2314
Bhattacharjee S, Bahl P, de Silva C, Doolan C, Chughtai AA, Heslop D, MacIntyre CR. Experimental Evidence for the Optimal Design of a High-Performing Cloth Mask. ACS Biomater Sci Eng. 2021 Jun 14;7(6):2791-2802. doi: 10.1021/acsbiomaterials.
Kalaiselvan P, Tummanapalli SS, Kumar Vijay A, Bahl P, MacIntyre CR, Willcox MDP. The ability of face masks to reduce transmission of microbes. Clin Exp Optom. 2022 Mar;105(2):214-221. doi: 10.1080/08164622.2021.1971050.
Li X, Ding P, Deng F, Mao Y, Zhou L, Ding C, Wang Y, Luo Y, Zhou Y, MacIntyre CR, Tang S, Xu D, Shi X. Wearing time and respiratory volume affect the filtration efficiency of masks against aerosols at different sizes. Environ Technol Innov. 2022 Feb;25:102165. doi: 10.1016/j.eti.2021.102165.
Bhattacharjee S; Joshi R; Chughtai A; Heslop D; Wilcox M; MacIntyre R, 2021, 'Graphene and nanoparticles coated antimicrobial and biocompatible cotton/silk fabrics for protective clothing', ACS Applied Bio Materials
Scott N; Saul A; Spelman T; Stoove M; Pedrana A; Saeri A; Grundy E; Smith L; Toole M; McIntyre CR; Crabb BS; Hellard M, 2021, 'The introduction of a mandatory mask policy was associated with significantly reduced COVID-19 cases in a major metropolitan city', PLOS ONE, vol. 16, http://dx.doi.org/10.1371/journal.pone.0253510
Bahl P; de Silva C; Bhattacharjee S; Stone H; Doolan C; Chughtai AA; MacIntyre CR, 2021, 'Droplets and Aerosols Generated by Singing and the Risk of Coronavirus Disease 2019 for Choirs', Clinical infectious diseases : an official publication of the Infectious Diseases Society of America, vol. 72, pp. e639 - e641, http://dx.doi.org/10.1093/cid/ciaa1241
MacIntyre CR; Nguyen PY; Chughtai AA; Trent M; Gerber B; Steinhofel K; Seale H, 2021, 'Mask use, risk-mitigation behaviours and pandemic fatigue during the COVID-19 pandemic in five cities in Australia, the UK and USA: A cross-sectional survey', International Journal of Infectious Diseases, vol. 106, pp. 199 - 207, http://dx.doi.org/10.1016/j.ijid.2021.03.056
Costantino V; Raina MacIntyre C, 2021, 'The Impact of Universal Mask Use on SARS-COV-2 in Victoria, Australia on the Epidemic Trajectory of COVID-19', Frontiers in Public Health, vol. 9, http://dx.doi.org/10.3389/fpubh.2021.625499
Najmi A; Nazari S; Safarighouzhdi F; Raina MacIntyre C; Miller EJ; Rashidi TH, 2021, 'Facemask and social distancing, pillars of opening up economies', PLoS ONE, vol. 16, pp. e0249677, http://dx.doi.org/10.1371/journal.pone.0249677
Ma T; Heywood A; MacIntyre CR, 2021, 'Travel health seeking behaviours, masks, vaccines and outbreak awareness of Australian Chinese travellers visiting friends and relatives – Implications for control of COVID-19', Infection, Disease and Health, vol. 26, pp. 38 - 47, http://dx.doi.org/10.1016/j.idh.2020.08.007
Chughtai AA; Seale H; Rawlinson WD; Kunasekaran M; Raina Macintyre C, 2021, 'Selection and use of respiratory protection by healthcare workers to protect from infectious diseases in hospital settings', Annals of Work Exposures and Health, vol. 64, pp. 368 - 377, http://dx.doi.org/10.1093/ANNWEH/WXAA020
de Silva CM; Bahl P; Doolan C; MacIntyre CR, 2021, 'Bespoke flow experiments to capture the dynamics of coughs and sneezes', MEASUREMENT SCIENCE AND TECHNOLOGY, vol. 32, http://dx.doi.org/10.1088/1361-6501/ac2010
Bhattacharjee S, Bahl P, de Silva C, Doolan C, Chughtai AA, Heslop D, MacIntyre CR. Experimental Evidence for the Optimal Design of a High-Performing Cloth Mask. ACS Biomater Sci Eng. 2021 Jun 14;7(6):2791-2802.
MacIntyre CR, Nguyen PY, Chughtai AA, Trent M, Gerber B, Steinhofel K, Seale H. Mask use, risk-mitigation behaviours and pandemic fatigue during the COVID-19 pandemic in five cities in Australia, the UK and USA: A cross-sectional survey. Int J Infect Dis. 2021 May;106:199-207.
MacIntyre CR, Costantino V, Bian L, Bethel C. Effectiveness of facemasks for opening a university campus in Mississippi, United States - a modelling study. J Am Coll Health. 2021 Feb 19:1-6. doi: 10.1080/07448481.2020.1866579.
Tang S, Mao Y, Jones RM, Tan Q, Ji JS, Li N, Shen J, Lv Y, Pan L, Ding P, Wang X, Wang Y, MacIntyre CR, Shi X. Aerosol transmission of SARS-CoV-2? Evidence, prevention and control. Environ Int. 2020 Nov;144:106039. doi: 10.1016/j.envint.2020.106039.
Bahl P, Bhattacharjee S, de Silva C, Chughtai AA, Doolan C, MacIntyre CR. Face coverings and mask to minimise droplet dispersion and aerosolisation: a video case study. Thorax. 2020 Nov;75(11):1024-1025. doi: 10.1136/thoraxjnl-2020-215748
Bhattacharjee S, Joshi R, Chughtai AA, Macintyre CR. Graphene Modified Multifunctional Personal Protective Clothing. Adv Mater Interfaces. 2019 Nov 8;6(21):1900622. doi: 10.1002/admi.201900622. Epub 2019 Aug 20.
MacIntyre CR, Chughtai AA. A RAPID SYSTEMATIC REVIEW OF THE EFFICACY OF FACE MASKS AND RESPIRATORS AGAINST CORONAVIRUSES AND OTHER RESPIRATORY TRANSMISSIBLE VIRUSES FOR THE COMMUNITY, HEALTHCARE WORKERS AND SICK PATIENTS IJNS.2020
Bahl, P., Doolan, C., de Silva, C., Chughtai, A. A., Bourouiba, L., & MacIntyre, C. R. (2020). Airborne or droplet precautions for health workers treating COVID-19?. J Infect Dis. doi:10.1093/infdis/jiaa189
Bhattacharjee, Shovon; Joshi, Rakesh; Chughtai, Abrar Ahmad; Macintyre, Chandini Raina. Graphene Modified Multifunctional Personal Protective Clothing. Advanced Materials Interfaces, 20 Aug 2019. doi: 10.1002/admi.201900622
C Raina MacIntyre, S Jay Hasanain. Community Universal Face Mask Use during the COVID 19 pandemic—from households to travelers and public spaces, Journal of Travel Medicine, , taaa056, https://doi.org/10.1093/jtm/taaa056
Chughtai AA, Seale H, Islam MS, Owais M, Macintyre CR. Policies on the use of respiratory protection for hospital health workers to protect from coronavirus disease (COVID-19). Int J Nurs Stud. 2020 Mar 13;105:103567. doi: 10.1016/j.ijnurstu.2020.103567. [Epub ahead of print] No abstract available.
Islam, M. S., Chughtai, A. A., & Seale, H. (2020). Reflecting on the updates to the World Health Organisation 2019 Tuberculosis Infection Control Guidelines through the lens of a low-income/high TB burden country. Journal of Infection and Public Health. doi:10.1016/j.jiph.2020.02.039
Chughtai, A. A., Seale, H., Rawlinson, W. D., Kunasekaran, M., & Macintyre, C. R. (2020). Selection and Use of Respiratory Protection by Healthcare Workers to Protect from Infectious Diseases in Hospital Settings.. Ann Work Expo Health. doi:10.1093/annweh/wxaa020
Chughtai, A. A., & Khan, W. (2020). Use of personal protective equipment to protect against respiratory infections in Pakistan: A systematic review. Journal of Infection and Public Health, 13(3), 385-390. doi:10.1016/j.jiph.2020.02.032
Chughtai AA; Stelzer-Braid S; Rawlinson W; Pontivivo G; Wang Q; Pan Y; Zhang D; Zhang Y; Li L; MacIntyre CR, 2019, 'Contamination by respiratory viruses on outer surface of medical masks used by hospital healthcare workers', BMC Infectious Diseases, vol. 19, http://dx.doi.org/10.1186/s12879-019-4109-x
Chughtai AA, Chen X, Macintyre CR, 2018, 'Risk of self-contamination during doffing of personal protective equipment', American Journal of Infection Control, http://dx.doi.org/10.1016/j.ajic.2018.06.003
MacIntyre CR, Chughtai AA, Rahman B, Peng Y, Zhang Y, Seale H, et al. The efficacy of medical masks and respirators against respiratory infection in health workers. Influenza and other respiratory viruses. 2017
MacIntyre CR, Chughtai AA, Rahman B, Peng Y, Zhang Y, Seale H, et al. The efficacy of medical masks and respirators against respiratory infection in health workers. Influenza and other respiratory viruses. 2017.
Shohini Mukerji, C. Raina MacIntyre, Holly Seale, Quanyi Wang, Peng Yang, Xiaoli Wang, and Anthony T. Newall Cost-effectiveness analysis of N95respirators and medical masks to protect healthcare workers in China from respiratory infections, BMC Infectious Diseases (2017) 17:464 [Full text]
Chen X;Chughtai AA;MacIntyre CR, 2016, 'Herd protection effect of N95 respirators in healthcare workers.', J Int Med Res, http://dx.doi.org/10.1177/0300060516665491, ROS ID: 853542
MacIntyre CR;Zhang Y;Chughtai AA;Seale H;Zhang D;Chu Y;Zhang H;Rahman B;Wang Q, 2016, 'Cluster randomised controlled trial to examine medical mask use as source control for people with respiratory illness', BMJ Open, vol. 6, http://dx.doi.org/10.1136/bmjopen-2016-012330, ROS ID: 866220
MacIntyre CR, Wang Q, Seale H, Yang P, Shi W, Gao Z, et al. A randomized clinical trial of three options for N95 respirators and medical masks in health workers. American journal of respiratory and critical care medicine. 2013;187(9):960-6.
MacIntyre CR, Wang Q, Cauchemez S, Seale H, Dwyer DE, Yang P, et al. A cluster randomized clinical trial comparing fit-tested and non-fit-tested N95 respirators to medical masks to prevent respiratory virus infection in health care workers. Influenza and other respiratory viruses. 2011;5(3):170-9.
Chughtai AA, MacIntyre CR, Peng Y, Wang Q, Ashraf MO, Dung TC, et al. Practices around the use of masks and respirators among hospital health care workers in 3 diverse populations. . American journal of infection control. 2015;43:1116-8.
Chughtai AA, MacIntyre CR, Zheng Y, Wang Q, Toor ZI, Dung TC, et al. Examining the policies and guidelines around the use of masks and respirators by healthcare workers in China, Pakistan and Vietnam. J Infect Prev. 2015;16(2):68–74.
Chughtai AA, Seale H, Chi Dung T, Maher L, Nga PT, MacIntyre CR. Current practices and barriers to the use of facemasks and respirators among hospital-based health care workers in Vietnam. American journal of infection control. 2015;43(1):72-7.
Chughtai AA, Seale H, Dung TC, Hayen A, Rahman B, MacIntyre CR. Compliance with the use of medical and cloth masks among healthcare workers in Vietnam. Ann Occup Hyg. 2016:1-12.
Macintyre CR, Seale H, Yang P, Zhang Y, Shi W, Almatroudi A, et al. Quantifying the risk of respiratory infection in healthcare workers performing high-risk procedures. Epidemiology and infection. 2014;142(9):1802-8.
Seale H, Corbett S, Dwyer DE, MacIntyre CR. Feasibility exercise to evaluate the use of particulate respirators by emergency department staff during the 2007 influenza season. Infection control and hospital epidemiology : the official journal of the Society of Hospital Epidemiologists of America. 2009;30(7):710-2.
MacIntyre CR, Ridda I, Seale H, Gao Z, Ratnamohan VM, Donovan L, et al. Respiratory viruses transmission from children to adults within a household. Vaccine. 2012;30(19):3009-14.
MacIntyre CR, Wang Q, Rahman B, Seale H, Ridda I, Gao Z, et al. Efficacy of face masks and respirators in preventing upper respiratory tract bacterial colonization and co-infection in hospital healthcare workers. Preventive medicine. 2014;62:1-7.
Seale H, Leem J-S, Gallard J, Kaur R, Chughtai AA, Tashani M, et al. “The cookie monster muffler”: Perceptions and behaviours of hospital healthcare workers around the use of masks and respirators in the hospital setting. IJIC. 2014;1(i):1-8.
Yang P, Seale H, MacIntyre CR, Zhang H, Zhang Z, Zhang Y, et al. Mask-wearing and respiratory infection in healthcare workers in Beijing, China. Braz J Infect Dis. 2011;15(2):102-8.
Chughtai AA, Seale H, MacIntyre CR. Availability, consistency and evidence-base of policies and guidelines on the use of mask and respirator to protect hospital health care workers: a global analysis. BMC research notes. 2013;6:216.
MacIntyre CR, Chughtai AA, Seale H, Richards GA, Davidson PM. Respiratory protection for healthcare workers treating Ebola virus disease (EVD): Are facemasks sufficient to meet occupational health and safety obligations? Int J Nurs Stud. 2014;51(11):1421-6.
MacIntyre CR, Chughtai AA, Seale H, Richards GA, Davidson PM. Response to Martin-Moreno et al. (2014) Surgical mask or no mask for health workers not a defensible position for Ebola. Int J Nurs Stud. 2014;51(12):1694-5.
Mukerji S, MacIntyre CR, Newall AT. Review of economic evaluations of mask and respirator use for protection against respiratory infection transmission. BMC infectious diseases. 2015;15(1):1.
Seale, H., Corbett, S., Dwyer, D.E., MacIntyre, C.R. Feasibility exercise to evaluate the use of particulate respirators by emergency department staff during the 2007 influenza season
(2009) Infection Control and Hospital Epidemiology, 30 (7), pp. 710-712.
Seale H, Dwyer DE, Cowling BJ, Wang Q, Yang P, Macintyre CR. A review of medical masks and respirators for use during an influenza pandemic. Influenza and other respiratory viruses. 2009;3(5):205-6.
Chughtai AA, Seale H, MacIntyre CR. Use of cloth masks in the practice of infection control–evidence and policy gaps. IJIC. 2013;9(3):1-12.