An official website of the United States government.

We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Indoor Air and COVID-19 Key References and Publications

This page lists some of the technical publications addressing the science related to transmission of SARS-Co-V-2 through aerosol in indoor environments. This is an area of active research that is fast developing. References will be updated periodically.

Multiple scientific journal articles have been published related to the issue of potential airborne transmission of SARS-Co-V-2 through aerosols (also referred to as droplet nuclei). The rationale for consideration is based on multiple, growing, lines of evidence: 1) Reports of measurement of the virus in the air, including beyond the distance recommended for droplet transmission, 2) Physically-based models of emissions of virus-laden aerosols and their dynamics, 3) Evidence of airborne transmission for the closely-related coronaviruses that caused the SARS and MERS outbreaks 4) Epidemiological evidence suggestive of possible airborne transmission, though other routes cannot be excluded.

The relative importance of this potential route of SARS-CoV2 transmission in comparison to others (close-contact, fomites) has not been established at this point. This increasing weight of evidence supports the use of precautions against transmission of SARS-Co-V- 2 in indoor environments as an addition to other measures already known to limit it.

Topics on this page: 

General

Top of Page

Reports of Measurements in Aerosols

  • van Doremalen et al. Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1. The New England journal of medicine, 2020; 382: 1564-7.
  • Santarpia et al. 2020. Transmission potential of SARS-CoV-2 in viral shedding observed at the University of Nebraska Medical Center.medRxiv, 2020: 2020.03.23.20039446.
  • Chia et al. 2020. Detection of air and surface contamination by SARS-CoV-2 in hospital rooms of infected patients. Nature communications, 11(1), 1-7.
  • Nissen et al. 2020. Long-distance airborne dispersal of SARS-CoV-2 in COVID-19 wards. Exit
  • Fears et al. Persistence of severe acute respiratory syndrome coronavirus 2 in aerosol suspensions. Emerg Infect Dis. 2020 S
  • Guo et al. 2020. Early Release - Aerosol and Surface Distribution of Severe Acute Respiratory Syndrome Coronavirus 2 in Hospital Wards, Wuhan, China, Volume 26, Number 7—July 2020 - Emerging Infectious Diseases journal - CDC. doi:10.3201/eid2607.200885
  • Ong et al. 2020. Air, surface environmental, and personal protective equipment contamination by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a symptomatic patient. JAMA, 323(16), 1610-1612. doi:10.1001/jama.2020.3227
  • Zhou et al. 2020.  Investigating SARS-CoV-2 surface and air contamination in an acute healthcare setting during the peak of the COVID-19 pandemic in LondonPublished by Oxford University Press for the Infectious Diseases Society of America.

Top of Page

Physically-based Modeling of Aerosol Dynamics

  • Liu et al. 2017. Short‐range airborne transmission of expiratory droplets between two people. Indoor Air. 27:452‐462.
  • Riediker and Tsai. 2020. Estimation of SARS-CoV-2 emissions from non-symptomatic cases. medRxiv.
  • Buonanno et al. 2020. Estimation of airborne viral emission: quanta emission rate of SARS-CoV-2 for infection risk assessment. Environment International, 105794.
  • Johnson et al. 2011. Modality of human expired aerosol size distributions. Journal of Aerosol Science42(12), 839-851.
  • Qian and Zheng. 2018. Ventilation control for airborne transmission of human exhaled bio-aerosols in buildings. J Thorac Dis. 2018;10(S9):S2295-S2304. doi:10.21037/jtd.2018.01.24.

Top of Page

Evidence of Airborne Transmission for SARS and MERS

  • Yu et al. 2004. Evidence of airborne transmission of the severe acute respiratory syndrome virus. New England Journal of Medicine, 350(17), 1731-1739. doi:10.1056/NEJMoa032867.
  • Xiao et al. 2018. A study of the probable transmission routes of MERS‐CoV during the first hospital outbreak in the Republic of Korea. Indoor Air, 28(1), 51-63.

Top of Page

Epidemiological Evidence Suggestive of Transmission Through Aerosol

Top of Page

Other

  • Anfinrud et al. 2020. Visualizing speech-generated oral fluid droplets with laser light scattering. N Engl J Med 2020; published online April 15. DOI:10.1056/NEJMc2007800.
  • Arslan et al. 2020. Transmission of SARS-CoV-2 via fecal-oral and aerosols–borne routes. Science of the Total Environment 743 (2020) 140709.
  • Bourouiba. 2020. Turbulent Gas Clouds and Respiratory Pathogen Emissions Potential Implications for Reducing Transmission of COVID-19. JAMA Insights. Mar. 26. 2020.
  • Colaneri et al. 2020. SARS-CoV-2 RNA contamination of inanimate surfaces and virus viability in a health care emergency unit. Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases.16.
  • Chin et al. 2020. Stability of SARS-CoV-2 in different environmental conditions. The Lancet Microbe, 2020; 1: e10.
  • Eslam and Jali. 2020. The role of environmental factors to transmission of SARS-CoV-2 (COVID-19). AMB Express 10 (1), 1–8.
  • Fears et al. 2020. Comparative dynamic aerosol efficiencies of three emergent coronaviruses and the unusual persistence of SARS-CoV-2 in aerosol suspensions. medRxiv 2020 preprint DOI. Exit
  • Furukawa. 2020. Early Release - Evidence Supporting Transmission of Severe Acute Respiratory Syndrome Coronavirus 2 While Presymptomatic or Asymptomatic - Volume 26, Number 7 —July 2020 - Emerging Infectious Diseases journal - CDC. Exit
  • He et al. 2020. Temporal dynamics in viral shedding and transmissibility of COVID-19. Nature medicine. 26: 672-5.
  • Richard et al. 2020. SARS-CoV-2 is transmitted via contact and via the air between ferrets. Nature Communications. NATURE COMMUNICATIONS.
  • Lewis. 2020. Is the coronavirus airborne? Experts can’t agree. Nature; 580: 175.
  • Lu et al. 2020. COVID-19 outbreak associated with air conditioning in restaurant, Guangzhou, China. Emerg. Infect. Dis. 26 (7).
  • Milton et al. 2013. Influenza virus aerosols in human exhaled breath: Particle size, culturability, and effect of surgical masks. PLoS Pathog. 2013;9:e1003205.
  • Morawska et al. 2009. Size distribution and sites of origin of droplets expelled from the human respiratory tract during expiratory activities. Journal of Aerosol Science.40:256–269.
  • Mutuku. 2020. An Overview of Experiments and Numerical Simulations on Airflow and Aerosols Deposition in Human Airways and the Role of Bioaerosol Motion in COVID-19 Transmission. Aerosol and Air Quality Research, 20: 1172–1196, 2020 ISSN: 1680-8584 print / 2071-1409.Exit
  •  Nishiura, et al. 2020. Closed environments facilitate secondary transmission of coronavirus disease 2019 (COVID-19). medRxiv 2020 preprint DOI.
  • Prather et al. 2020. Reducing transmission of SARS-CoV-2. Science 10.1126/science.abc6197 (2020).
  • Scheuch. 2020. Breathing Is Enough For the Spread of Influenza Virus and SARS COV2. JOURNAL OF AEROSOL MEDICINE AND PULMONARY DRUG DELIVERY Volume 33, Number 4. Mary Ann Liebert, Inc. Pp. 1–5 DOI: 0.1089/jamp.2020.1616.
  • Shi, J. et al. 2020. Susceptibility of ferrets, cats, dogs, and other domesticated animals to SARS–coronavirus 2. Science 368, 1016–1020.
  • Somsen. 2020. Small droplet aerosols in poorly ventilated spaces and SARS-CoV-2 transmission. Lancet Respir Med 2020. Published Online May 27, 2020. Exit
  • Stadnytskyi et al. 2020. The airborne lifetime of small speech droplets and their potential importance in SARS-CoV-2 transmissionPNAS. Published online May 13, 2020. doi:10.1073/pnas.2006874117
  • Sze et al. 2010. Review and comparison between the Wells–Riley and dose-response approaches to risk assessment of infectious respiratory diseases. Indoor Air. 2010;20:2–16
  • Thatcher. 2002.  Effects of room furnishings and air speed on particle deposition rates indoors. Atmospheric Environment. 2002;36:1811–1819.
  • Wang et al. 2020. Study of SARS transmission via liquid droplets in air. J Biomech Eng. 2005;127:32–38.
  • Wang and Du. 2020. COVID-19 may transmit through aerosol. Ir. J. Med. Sci. (1971-)1–2.
  • Wang et al. 2020. High Temperature and High Humidity Reduce the Transmission of COVID-19. (Available at SSRN 3551767).
  • Wu et al. 2020. Environmental contamination by SARS-CoV-2 in a designated hospital for coronavirus disease 2019. Am J Infect Control.
  • Ye et al. 2020. Environmental contamination of SARS-CoV-2 in healthcare premises. The Journal of infection.

Top of Page

Return to Indoor Air Quality and Coronavirus (COVID-19).