It is not clear yet how SARS-CoV-2 spreads from person-to-person, however there are indications that person-to-person spread is occurring, likely between close contacts. Officials are working to understand implications of possible transmission from infected but asymptomatic persons.

Previous coronaviruses causing illness in people include Severe Acute Respiratory Syndrome, SARS, and Middle East Respiratory Syndrome, MERS. When person-to-person spread occurs with MERS and SARS, it is thought to have happened mainly via respiratory droplets produced when an infected person coughs or sneezes, similar to how influenza and other respiratory pathogens spread. The spread of MERS and SARS between people generally occurred between close contacts.

WHO VIDEO: How to handwash? With soap and water (YouTube)

CDC: Inactivation of Severe Acute Respiratory Syndrome Coronavirus 2 by WHO-Recommended Hand Rub Formulations and Alcohols, A. Kratzel, et al., 13 April 2020

CDC: What every American and community can do now to decrease the spread of the coronavirus (PDF)

CDC: Emerging Infectious Diseases: Prolonged Persistence of SARS-CoV-2 RNA in Body Fluids, Sun J. rolonged persistence of SARS-CoV-2 RNA in body fluids. Emerg Infect Dis. 2020 Aug [online 8 May2020]

CDC: Evidence for Limited Early Spread of COVID-19 Within the United States, January–February 2020 (Early release, May 29, 2020)

CDC: When You Can be Around Others After You Had or Likely Had COVID-19 (May 24, 2020)

CDC: Considerations for Wearing Masks: Help Slow the Spread of COVID-19

– Discussion of mask use with a note that face shields are not recommended for everyday activities or as a substitute for a mask.

CDC/MMWR: SARS-CoV-2 Transmission and Infection Among Attendees of an Overnight Camp — Georgia, June 2020, C. Szablewski, et al., 31 July 2020 – Understanding successful interventions to prevent and mitigate SARS-CoV-2 transmission in overnight camps has important implications for similar congregate settings such as day camps and schools with the same age range.

rmedRxiv: The Infectious Nature of Patient-Generated SARS-CoV-2 Aerosol, J. Santarpia, et al., 21 July 2020

EHS Today: Virginia Passes First-In-Nation OSHA Standard for COVID-19, 16 July 2020

Wall Street Journal: Face Masks Really Do Matter. The Scientific Evidence Is Growing.

San Francisco Department of the Environment: Safer COVID-19 cleaning products and disinfectants

The American Lung Association: From the Frontlines: The Truth About Masks and COVID-19

VuMedi: SARS-CoV-2 Transmission Myths: Is SARS-CoV-2 Airborne Transmitted? Why is Important to Know The Difference Between Respiratory Droplets and Droplet Nuclei?, Edward A. Nardell, 30 July 2020 – Discussions regarding how SARS-CoV-2 is spread. The presentations review the data regarding each mode of transmission. You may have to log in and provide a password, but lots of interesting podcasts.

VuMedi: Airborne Transmission & Face Masks: How Do Different Types of Masks Protect Against Various Ranges of Transmitted Droplets? How Far Can Aerosolized Droplets Travel in the Air From an Uncovered Cough & For How Long? (video) , Siddhartha Verma, 30 July 2020 – Discussion of potential transmission modes of SARS-CoV-2. You may have to log in and provide a password, but lots of interesting podcasts.

VuMedi: COVID-19 Airborne Transmission Analysis: How Can Airborne Transmission of COVID-19 Indoors Be Minimized? How Are Infections Transmitted and Does Transmission Route Make a Difference?

JAMA: Association Between Statewide School Closure and COVID-19 Incidence and Mortality in the US (PDF) , K. Auger, et al., 29 July 2020 – determine if school closure and its timing were associated with decreased COVID-19 incidence and mortality.

Transmission

CDC: How COVID-19 Spreads – This page has been updated for clarity. 22 May 2020

CDC/MMWR: Preventing and Mitigating SARS-CoV-2 Transmission — Four Overnight Camps, Maine, June–August 2020, L. Blaisdell, et al., 26 August 2020

JAMA Network: Assessment of SARS-CoV-2 Transmission on an International Flight Among a Tourist Group, Hoehl S., et.al (Aug. 18, 2020) (PDF) – This case series assessed a commercial airline flight from Tel Aviv, Israel, to Frankfurt, Germany, that occurred on March 9th, 2020. Among 102 passengers on a Boeing 737-900 aircraft were 24 members of a tourist group.

ASHRAE Journal: Ventilation and Transport: Bioaerosols in

Health-Care Environments (PDF) August 2014 – A series of tests were conducted in an actual hospital to observe containment and removal of synthetic respiratory aerosols with respect to directional airflow and air change rate within a general patient room, an airborne infection isolation room and patient corridor.

Nature: SARS-CoV-2 failure to infect or replicate in mosquitoes: an extreme challenge, Y. S. Huang, et al., 17 July 2020

Cell Host & Microbe: Infection and Rapid Transmission of SARS-CoV-2 in Ferrets (PDF) . Kim, Y et al, 13 May 2020 – Kim et al. show that ferrets are highly susceptible to SARS-CoV-2 infection and effectively transmitthe virus by direct or indirect contact,recapitulating human infection and transmission.

Science: Susceptibility of ferrets, cats, dogs, and other domesticated animals to SARS–coronavirus 2. Shi, J et al, 29 May 2020 – The authors found that SARS-CoV-2 infects the upper respiratory tracts of ferrets but is poorly transmissible between individuals.

PloS One: Exhaled Air Dispersion during Coughing with and without Wearing a Surgical or N95 Mask, Hui DS, et al. PLoS One (5 December 2012)

American College of Surgeons (ACS): Infectious Dose Can it Inform COVID-19 Decisions? (PDF) , Brosseau, L., 30 June 2020 – Slide presentation which includes data supporting aerosol transmission, how the decision is made for novel aerosols; examples of job activiteis where aerosol transmission is likely, infectious dose for SARS-CoV-2 and more.

Occupational Health Clinics for Ontario Workers Inc. (OHCOW): Using Infectious Dose to Understand Risk (PDF) , Brosseau, L. – These slides focus on infectious dose and risk for infection

OHCOW: Covid 19 Transmission Taking Stock of the Science (YouTube Video) , Moderated by Dr. Raymond Tellier, 8 July 2020

OHCOW: The Role of Infectious Dose in Identifying and Managing COVID-19 Risks (YouTube Video) , Moderated by Dr. Kevin Hedges, 15 July 2020 – International experts in infection control, occupational hygiene, and respiratory protection will discuss up to science, controls and methodology related to exposure to coronavirus and prevention of COVID-19. This session will build on the science delivered in session 1, and provide advice on the importance of the hierarchy of controls (HOC) which includes ventilation as a higher order control along with appropriate and effective personal protective equipment (PPE).

Speaker Slides (PDFs)

Cloth Face Covering

ACS Publications: Aerosol Filtration Efficiency of Common Fabrics Used in Respiratory Cloth Masks, A. Konda, et al., 24 April 2020 – This paper describes the filtration efficiency of several types of fabric and combinations of fabrics.

AIP – Physics of Fluids: Visualizing the effectiveness of face masks in obstructing respiratory jetsS. Verma, et al., 30 June 2020 – This paper presents the experimental design for evaluating visualization experiments to assess qualitatively the effectiveness of face masks

California Dept. of Health: Guidance for the use of Face Coverings (PDF) – The state of California provides guidance and exemptions for using face covering

Detection of SARS-CoV-2 in stool

The Lancet: Prolonged presence of SARS-CoV-2 viral RNA in faecal samples. Wu, Y et al., 1 May 2020 – Real-time RT-PCR results of all respiratory and faecal samples from patients with coronavirus disease 2019 (COVID-19) at the Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China

VuMedi: Update on Airborne Transmission of SARS-CoV-2: Can Far UV Light Help Us Get Back to Business As Usual? Is it Safe for Prolonged Exposure?, Brenner D. Columbia University Irving Medical Center, New York, NY.

Journal of Medical Virology: J. Med Virology. The Presence of SARS-CoV-2 RNA in the Feces of COVID-19 Patients. Chen, Y. et al. 3 April 2020 – presence of SARS‐CoV‐2 RNA in the feces of COVID‐19 patients and suggested the possibility of SARS‐CoV‐2 transmission via the fecal‐oral route

preprint, not yet peer-reviewed: Prolonged presence of SARS-CoV-2 in feces of pediatric patients during the convalescent phase. Xing Y, et al., 13 March 2020 – RT-PCR on throat swabs and fecal samples of three children.

CDC Emerging Infectious Diseases Journal. [Early release]: Infectious SARS-CoV-2 in Feces of Patient with Severe COVID-19. Xiao, F. et al., 18 May 2020 – We collected feces specimens from 28 patients; 12, including the patient described in this report, were positive for viral RNA for >1 time point. We attempted to isolate SARS-CoV-2 virus from 3 of the viral RNA–positive patient. Results were successful for 2 of 3 patients, including the patient from this report, indicating that infectious virus in feces is a common manifestation of COVID-19.